Service & Maintenance Manual - JLG Industriescsapps.jlg.com/OnlineManuals/Manuals/JLG/JLG Scissor Lifts/330_400CRT... · maintenance are inserted at the appropriate point in the manual

Service & Maintenance Manual

Model

330CRT400CRT

3121804April 7, 2004

INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS

3121804 – JLG Lift – a

SECTION A. INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS

A.A GENERAL

This section contains the general safety precautionswhich must be observed during maintenance of theaerial platform. It is of utmost importance that main-tenance personnel pay strict attention to these warn-ings and precautions to avoid possible injury tothemselves or others, or damage to the equipment.A maintenance program must be followed to ensurethat the machine is safe to operate.

MODIFICATION OF THE MACHINE WITHOUT CERTIFI-CATION BY A RESPONSIBLE AUTHORITY THAT THEMACHINE IS AT LEAST AS SAFE AS ORIGINALLYMANUFACTURED, IS A SAFETY VIOLATION.

The specific precautions to be observed duringmaintenance are inserted at the appropriate point inthe manual. These precautions are, for the mostpart, those that apply when servicing hydraulic andlarger machine component parts.

Your safety, and that of others, is the first consider-ation when engaging in the maintenance of equip-ment. Always be conscious of weight. Never attemptto move heavy parts without the aid of a mechanicaldevice. Do not allow heavy objects to rest in anunstable position. When raising a portion of theequipment, ensure that adequate support is pro-vided.

SINCE THE MACHINE MANUFACTURER HAS NODIRECT CONTROL OVER THE FIELD INSPECTIONAND MAINTENANCE, SAFETY IN THIS AREA RESPON-SIBILITY OF THE OWNER/OPERATOR.

A.B HYDRAULIC SYSTEM SAFETY

It should be noted that the machines hydraulic sys-tems operate at extremely high potentially danger-ous pressures. Every effort should be made torelieve any system pressure prior to disconnectingor removing any portion of the system.

Relieve system pressure by cycling the applicablecontrol several times with the engine stopped andignition on, to direct any line pressure back into thereservoir. Pressure feed lines to system componentscan then be disconnected with minimal fluid loss.

A.C MAINTENANCE

FAILURE TO COMPLY WITH SAFETY PRECAUTIONSLISTED IN THIS SECTION MAY RESULT IN MACHINEDAMAGE, PERSONNEL INJURY OR DEATH AND IS ASAFETY VIOLATION.

• NO SMOKING IS MANDATORY. NEVER REFUEL DUR-ING ELECTRICAL STORMS. ENSURE THAT FUEL CAPIS CLOSED AND SECURE AT ALL OTHER TIMES.

• REMOVE ALL RINGS, WATCHES AND JEWELRYWHEN PERFORMING ANY MAINTENANCE.

• DO NOT WEAR LONG HAIR UNRESTRAINED, ORLOOSE-FITTING CLOTHING AND NECKTIES WHICHARE APT TO BECOME CAUGHT ON OR ENTANGLEDIN EQUIPMENT.

• OBSERVE AND OBEY ALL WARNINGS AND CAU-TIONS ON MACHINE AND IN SERVICE MANUAL.

• KEEP OIL, GREASE, WATER, ETC. WIPED FROMSTANDING SURFACES AND HAND HOLDS.

• USE CAUTION WHEN CHECKING A HOT, PRESSUR-IZED COOLANT SYSTEM.

• NEVER WORK UNDER AN ELEVATED BOOM UNTILBOOM HAS BEEN SAFELY RESTRAINED FROM ANYMOVEMENT BY BLOCKING OR OVERHEAD SLING,OR BOOM SAFETY PROP HAS BEEN ENGAGED.

• BEFORE MAKING ADJUSTMENTS, LUBRICATING ORPERFORMING ANY OTHER MAINTENANCE, SHUTOFF ALL POWER CONTROLS.

• BATTERY SHOULD ALWAYS BE DISCONNECTEDDURING REPLACEMENT OF ELECTRICAL COMPO-NENTS.

• KEEP ALL SUPPORT EQUIPMENT AND ATTACH-MENTS STOWED IN THEIR PROPER PLACE.

• USE ONLY APPROVED, NONFLAMMABLE CLEANINGSOLVENTS.

INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS

b – JLG Lift – 3121804

REVISON LOG

Original Issue - April 13, 2000

Revised - August 17, 2000

Revised - September 28, 2001

Revised - October 18, 2002

Revised - April 7, 2004

TABLE OF CONTENTS

3121804 – JLG Lift – i

TABLE OF CONTENTS

SUBJECT - SECTION, PARAGRAPH PAGE NO.

SECTION A - INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS

A.A General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-aA.B Hydraulic System Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-aA.C Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-a

SECTION 1 - SPECIFICATIONS

1.1 Capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.2 Component Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.3 Performance Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.4 Torque Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21.5 Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21.6 Pressure Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51.7 Serial Number Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51.8 Limit Switches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51.9 Cylinder Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-61.10 Major Component Weights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-61.11 Critical Stability Weights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

SECTION 2 - PROCEDURES

2.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12.2 Servicing and Maintenance Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12.3 Lubrication Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22.4 Cylinders - Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32.5 Valves - Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32.6 Component Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-42.7 Wear Pads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-42.8 Cylinder Checking Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-42.9 Lift Cylinder Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-52.10 Lift Cylinder Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-92.11 Steer Cylinder Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-142.12 Oscillation Cylinder Bleeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-162.13 Magnetic Speed Pickup Cleaning Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-162.14 Pressure Setting Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-172.15 Limit Switch Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-182.16 Automatic Choke - Field Adjustment (DF-750) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-182.17 Electronic Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-192.18 Flash Codes and Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-212.19 Preventive Maintenance and Inspection Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-27

SECTION 3 - TROUBLESHOOTING

3.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.2 Troubleshooting Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.3 Hydraulic Circuit Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

TABLE OF CONTENTS

ii – JLG Lift – 3121804

LIST OF FIGURES

FIGURE NO. TITLE PAGE NO.

1-1. Lubrication Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-31-1. Torque Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-41-2. Serial Number Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-52-1. Arms and Platform Positioning and Support, Cylinder Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-62-2. 330CRT Lift Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-72-3. 400CRT LIft Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-82-4. Cylinder Barrel Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-92-5. Capscrew Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-92-6. Cylinder Rod Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-92-7. Tapered Bushing Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-102-8. Rod Seal Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-112-9. Wiper Seal Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-112-10. Installation of Head Seal Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-112-11. Piston Seal Kit Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-122-12. Tapered Bushing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-122-13. Seating the Tapered Bearing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-122-14. Poly-Pak Piston Seal Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-132-15. Rod Assembly Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-132-16. Steer Cylinder Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-142-17. Magnetic Speed Pickup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-162-18. Magnetic Speed Pickup Removal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-162-19. Valve Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-172-20. Automatic Choke Adjustment (DF-750) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-182-21. Analyzer Flow Chart - Sheet 1 of 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-232-22. Analyzer Flow Chart - Sheet 2 of 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-243-1. Electrical Schematic - Sheet 1 of 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-103-2. Electrical Schematic - Sheet 2 of 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-113-3. Hydraulic Schematic - Sheet 1 of 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-123-4. Hydraulic Schematic - Sheet 2 of 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-13

TABLE OF CONTENTS

3121804 – JLG Lift – iii

LIST OF TABLES

TABLE NO. TITLE PAGE NO.

1-1 Hydraulic Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21-2 Lubrication Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21-3 Lubrication Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31-4 Cylinder Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-61-5 Major Component Weights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-61-6 Critical Stability Weights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-62-1 Cylinder Component Torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-132-2 Holding Valve Torque Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-132-3 Help Messages and Flash Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-212-4 Machine Model Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-252-5 Machine Configuration Programming Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-262-6 Preventive Maintenance and Safety Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-283-1 Elevation System Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-23-2 Chassis Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-43-3 Hydraulic System Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-73-4 Electrical System Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

TABLE OF CONTENTS

iv – JLG Lift – 3121804

This page left blank intentionally.


3121804 – JLG Lift – 1-1

SECTION 1. SPECIFICATIONS

1.1 CAPACITIES

Hydraulic Oil Tank

Approximately 60.6 liters (16 U.S. gallons) w/15% airspace

Hydraulic System (Including Tank)

Approximately 75.7 liters (20 U.S. gallons)

Fuel Tank

Approximately 48.8 liters (13 U.S. gallons)

Engine Crankcase

Gasoline Engine

3.2 liters (3.4 quarts) w/filter

2.7 liters (2.9 quarts) w/o filter

Diesel Engine

5.1 liters (5.4 quarts) w/filter

4.6 liters (4.9 quarts) w/o filter

Coolant Capacity

13.2 liters (3.5 U.S. gallons)

1.2 COMPONENT DATA

Gasoline Engine

Manufacturer - Kubota 750 Dual Fuel

Displacement - 750 cc

Low RPM - 2200

High RPM - 3600

Alternator - 40 Amp external

Battery - 85 Amphour, 700 cold cranking amps @ -17.8°C(0° F)

Fuel Consumption

Low RPM - 4.9 lph (1.3 gph)

High RPM - 9 lph (2.4 gph)

Horsepower - 24.5 @ 3600 RPM

Diesel EngineManufacturer - Kubota 1105

Low RPM - 1500

High RPM - 3000

Alternator - 40 Amp

Battery - 85 Amphour, 700 cold cranking amps @ -17.8°C(0° F)

Fuel Consumption

Low RPM - 3.5 lph (.93 gph)

High RPM - 6.6 lph (1.7 gph)

21 kW @ 3000 RPM (28 Horsepower @ 3000 RPM)

Drive/Steer SystemToe-In - Adjust to 12.7 mm (1/2 inch) overall

Drive Motor Displacement- 400 cc

Drive Brake - Spring applied, hydraulic release, releasepressure - 20.7 bar (300 psi ) max.

Hydraulic Filter - Full flow paper ( Cartridge type)

10 Microns Nominal

Tires

Standard 30.4 x 10 loader pneumatic or foam filled

NOTE: Inflate pnuematic tire to 3.1 bar (45 psi )

1.3 PERFORMANCE DATA

Travel SpeedHigh drive - 5.6 kmh (3.5 mph)

Gradeability35%

Turning Radius (Inside)7 ft. (2 m)

Lift SpeedLift up - 330CRT - 36-40 seconds

400CRT - 53-55 seconds

Lift down - 330CRT - 36-40 seconds

400CRT - 49-51 seconds


1-2 – JLG Lift – 3121804

Platform Capacity330CRT - 450 kg (1,000 lb.)

400 CRT - 360 kg (800 lb.)

Platform Extension CapacityAll Models - 120 kg (250 lb)

Machine Weight330CRT - Approx. 4,409 kg (9,720 lb.)

440CRT - Approx. 5,601 kg (12,348 lb.)

Machine Platform Height (Fully Extended)330 CRT - 10 m (33 ft.)

400 CRT - 12 m (40 ft.)

Machine Platform Height (Platform Lowered)330 CRT - 1.7 m (66.5 in.)

400 CRT - 1.7 m (68.25 in.)

Machine Length3 m (10 ft. 2 in.)

Machine Width1.8 m (69 in.)

1.4 TORQUE REQUIREMENTSAll wheel lugs must be torqued at 142 Nm (105 ft lb) every50 hours.

1.5 LUBRICATION

NOTE: Hydraulic oils must have anti-wear qualities at leastto API Service Classification GL-3, and sufficientchemical stability for mobile hydraulic system ser-vice. JLG Industries recommends Mobilfluid 424hydraulic oil, which has an SAE viscosity indexof152.

NOTE: Aside from JLG recommendations, it is not advisableto mix oils of different brands or types, as they maynot contain the same required additives or be ofcomparable viscosities. If use of hydraulic oil otherthan Mobilfluid 424 is desired, contact JLG Indus-tries for proper recommendations.

Lubrication Specifications

Table 1-1. Hydraulic Oil

HYDRAULIC SYSTEM OPERATING TEMPERATURE RANGE

SAE VISCOSITY GRADE

0 to +23 degrees F (-18 to -5 degrees C)

10W

0 to +210 degrees F (-18 to +100 degrees C)

10W-20,10W-30

+50 to +210 degrees F (+10 to +100 degrees C)

20W-20

Table 1-2. Lubrication Specifications

KEY SPECIFICATIONS

MPG Multipurpose Grease having a minimum dripping point of 350 degrees F. Excellent water resistance and adhesive qualities, and being of extreme pres-

sure type. (Timken OK 40 pounds minimum.)

EPGL Extreme Pressure Gear Lube (oil) meeting API ser-vice classification GL-5 or MIL-Spec MIL-L-2105.

EO Engine (crankcase) Oil. Gas - API SF/SG class, MIL-L-2104. Diesel - API CC/CD class, MIL-L-2104B/

MIL-L-2104C.

HO Hydraulic Oil. API service classification GL-3, e.g. Mobil 424.


3121804 – JLG Lift – 1-3

��

1 2

3

��

Table 1-3. Lubrication Chart

INDEX NO

COMPONENT NUMBER/TYPE LUBE POINTS LUBE METHODINTERVAL

HOURS

1 Hydraulic Oil Reservoir Fill Cap/Drain Plug HO - Check HO Level HO - Change HO

10/500

2 Hydraulic Filter Element N/A Initial Change - 50 Hours 250

3 Rail Slides N/A MPG - Brush 100

4 Engine Crankcase Fill Cap/Drain Plug Check Engine Oil Level 10/100

5 *Slide Blocks Upper and Lower MPG 100

* Item 5 not shown on illustration. Item 5 pertains to itemsthroughout the machine.

KEY TO LUBRICANTS:

MPG - Multi-purpose Grease

EPGL - Extreme Pressure Gear Lube

HO - Hydraulic Oil (Mobil 424)

TO AVOID PERSONAL INJURY, USE SAFETY PROP FOR ALLMAINTENANCE REQUIRING PLATFORM TO BE ELEVATED.

NOTE: Be sure to lubricate like items on each side

NOTE: Recommended lubricating intervals are based onmachine operations under normal conditions. Formachines used in multi-shift operations and/orexposed to hostile environments or conditions, lubri-cation frequencies must be increased accordingly.

Operate hydraulic functions through one completecycle before checking hydraulic oil level in tank. Oilshould be visible in ADD sight window on hydraulictank. If oil is not visible, add oil until oil is visible inboth ADD and FULL sight windows on tank. Do notoverfill tank.

Any time the pump coupling is removed, coatsplines of coupling with Texaco Code 1912 greaseprior to assembly.

Figure 1-1. Lubrication Diagram


1-4 – JLG Lift – 3121804

Fig

ure

1-1.

To

rque

Cha

rt


3121804 – JLG Lift – 1-5

1.6 PRESSURE SETTINGS

Main Relief - 228 bar ± 3.4 bar (3300 psi ± 50 psi)

Steer Relief (Left) - max 179 bar (2600 psi)

Steer Relief (Right) - max 110 bar (1600 psi)

Lift Pressure - 330CRT - 159 bar (2300 psi)

400CRT - 172 bar (2500 psi)

Leveling Jacks Valve (If Equipped) - 83 bar (1200 psi)

1.7 SERIAL NUMBER LOCATIONS

For machine identification, a serial number plate is affixedto the machine. The plate is located on the leftt side of themachine between the fuel tank and the rear wheel. Inaddition, should the serial number plate be damaged ormissing, the machine serial number is stamped on the topof frame between the front wheels.

1.8 LIMIT SWITCHESThe machine is equipped with the following limit switches:

High Drive Speed Cut-Out - High drive speed is cut outwhen platform is raised above stowed (fully lowered) posi-tion.

Tilt Alarm - 3° - A horn is sounded and a warning light isilluminated when the machine is operated on a slope thatexceeds 3° with the platform raised. If the machine is oper-ated on a 3° slope with the platform completely lowered,only the warning light is illuminated.

Drive Cut-Out (400CRT only) - Drive function is cut-outwhen the machine reaches a preset height of 9.1 m. (30ft).

Figure 1-2. Serial Number Location


1-6 – JLG Lift – 3121804

1.9 CYLINDER SPECIFICATIONS

NOTE: All dimensions are given in inches (in), with the met-ric equivalent, centimeters (cm), in parentheses.

1.10 MAJOR COMPONENT WEIGHTS

1.11 CRITICAL STABILITY WEIGHTS

DO NOT REPLACE ITEMS CRITICAL TO STABILITY WITH ITEMSOF DIFFERENT WEIGHT OR SPECIFICATION (FOR EXAMPLE:FILLED TIRES, ENGINE) DO NOT MODIFY UNIT IN ANY WAY TOAFFECT STABILITY.

Table 1-4. Cylinder Specifications

Description Bore Stroke Rod Dia

Lift Cylinder(330CRT)

4.0(10.2)

63.7(161.8)

2.75(7.0)

Upper Lift Cylinder(400CRT)

3.0(7.62)

58.1(147.6)

2.75(7.0)

Lower Lift Cylinder(400CRT)

4.0(10.2)

58.1(147.6)

2.75(7.0)

Lockout Cylinder(Oscillating Axle)

3.0(7.6)

3.75(9.5)

1.25(3.2)

Leveling JackCylinder

2.0(5.1)

14.0(35.6)

1.25(3.2)

Steer Cylinder 2.5(6.4)

7.1(18.1)

1.25(3.2)

Table 1-5. Major Component Weights

Component Lb Kg

Fixed Platform 569 258

Platform Extension 230 104

Arm Assembly- 330CRT (Includes Lift Cylinder)

3200 1452

Arm Assembly- 400CRT (Includes Lift Cylinder)

3900 1769

Chassis with Foam Filled Tires 4980 2259

Table 1-6. Critical Stability Weights

Component Lb Kg

Tires (Balasted Only) 246 111

Engine (Gas) 136 62

Engine (Diesel) 93 42


3121804 – JLG Lift – 2-1

SECTION 2. PROCEDURES

2.1 GENERAL

This section provides information necessary to performmaintenance on the scissor lift. Descriptions, techniquesand specific procedures are designed to provide the saf-est and most efficient maintenance for use by personnelresponsible for ensuring the correct installation and oper-ation of machine components and systems.

WHEN AN ABNORMAL CONDITION IS NOTED AND PROCEDURESCONTAINED HEREIN DO NOT SPECIFICALLY RELATE TO THENOTED IRREGULARITY, WORK SHOULD BE STOPPED ANDTECHNICALLY QUALIFIED GUIDANCE OBTAINED BEFORE WORKIS RESUMED.

The maintenance procedures included consist of servic-ing and component removal and installation, disassemblyand assembly, inspection, lubrication and cleaning. Infor-mation on any special tools or test equipment is also pro-vided where applicable.

2.2 SERVICING AND MAINTENANCE GUIDELINES

General

The following information is provided to assist you in theuse and application of servicing and maintenance proce-dures contained in this chapter.

Safety and Workmanship

Your safety, and that of others, is the first considerationwhen engaging in the maintenance of equipment. Alwaysbe conscious of weight. Never attempt to move heavyparts without the aid of a mechanical device. Do not allowheavy objects to rest in an unstable position. When raisinga portion of the equipment, ensure that adequate supportis provided.

Cleanliness

1. The most important single item in preserving thelong service life of a machine is to keep dirt and for-eign materials out of the vital components. Precau-tions have been taken to safeguard against this.Shields, covers, seals, and filters are provided tokeep air, fuel, and oil supplies clean; however, theseitems must be maintained on a scheduled basis inorder to function properly.

2. At any time when air, fuel, or oil lines are discon-nected, clear adjacent areas as well as the openingsand fittings themselves. As soon as a line or compo-nent is disconnected, cap or cover all openings toprevent entry of foreign matter.

3. Clean and inspect all parts during servicing or main-tenance, and assure that all passages and openingsare unobstructed. Cover all parts to keep themclean. Be sure all parts are clean before they areinstalled. New parts should remain in their contain-ers until they are ready to be used.

Components Removal and Installation

4. Use adjustable lifting devices, whenever possible, ifmechanical assistance is required. All slings (chains,cables, etc.) should be parallel to each other and asnear perpendicular as possible to top of part beinglifted.

5. Should it be necessary to remove a component onan angle, keep in mind that the capacity of an eye-bolt or similar bracket lessens, as the angle betweenthe supporting structure and the componentbecomes less than 90°.

6. If a part resists removal, check to see whether allnuts, bolts, cables, brackets, wiring, etc., have beenremoved and that no adjacent parts are interfering.

Component Disassembly and Reassembly

When disassembling or reassembling a component, com-plete the procedural steps in sequence. Do not partiallydisassemble or assemble one part, then start on another.Always recheck your work to assure that nothing has beenoverlooked. Do not make any adjustments, other thanthose recommended, without obtaining proper approval.

Pressure-Fit Parts

When assembling pressure-fit parts, use an “anti-seize” ormolybdenum disulfide base compound to lubricate themating surface.

Bearings

1. When a bearing is removed, cover it to keep out dirtand abrasives. Clean bearings in nonflammablecleaning solvent and allow to drip dry. Compressedair can be used but do not spin the bearing.

2. Discard bearings if the races and balls (or rollers)are pitted, scored, or burned.


2-2 – JLG Lift – 3121804

3. If a bearing is found to be serviceable, apply a lightcoat of oil and wrap it in clean (waxed) paper. Do notunwrap reusable or new bearings until they areready to install.

4. Lubricate new or used serviceable bearings beforeinstallation. When pressing a bearing into a retaineror bore, apply pressure to the outer race. If the bear-ing is to be installed on a shaft, apply pressure to theinner race.

Gaskets

Check that holes in gaskets align with openings in themating parts. If it becomes necessary to hand-fabricate agasket, use gasket material or stock of equivalent materialand thickness. Be sure to cut holes in the right location, asblank gaskets can cause serious system damage.

Bolt Usage and Torque Application

1. Use bolts of proper length. A bolt which is too longwill bottom before the head is tight against its relatedpart. If a bolt is too short, there will not be enoughthread area to engage and hold the part properly.When replacing bolts, use only those having thesame specifications of the original, or one which isequivalent.

2. Unless specific torque requirements are given withinthe text, standard torque values should be used onheat-treated bolts, studs, and steel nuts, in accor-dance with recommended shop practices.

Hydraulic Lines and Electrical Wiring

Clearly mark or tag hydraulic lines and electrical wiring, aswell as their receptacles, when disconnecting or removingthem from the unit. This will assure that they are correctlyreinstalled.

Hydraulic System

1. Keep the system clean. If evidence of metal or rub-ber particles is found in the hydraulic system, drainand flush the entire system.

2. Disassemble and reassemble parts on clean worksurface. Clean all metal parts with non-flammablecleaning solvent. Lubricate components, asrequired, to aid assembly.

Lubrication

Service applicable components with the amount, type,and grade of lubricant recommended in this manual, atthe specified intervals. When recommended lubricants arenot available, consult your local supplier for an equivalentthat meets or exceeds the specifications listed.

Batteries

Clean batteries, using a non-metallic brush and a solutionof baking soda and water. Rinse with clean water. Aftercleaning, thoroughly dry batteries and coat terminals withan anti-corrosion compound.

Lubrication and Servicing

Components and assemblies requiring lubrication andservicing are shown in Section 1.

2.3 LUBRICATION INFORMATION

Hydraulic System

1. The primary enemy of a hydraulic system is contam-ination. Contaminants enter the system by variousmeans, e.g., using inadequate hydraulic oil, allowingmoisture, grease, filings, sealing components, sand,etc., to enter when performing maintenance, or bypermitting the pump to cavitate due to insufficientsystem warm-up or leaks in the pump supply (suc-tion) lines.

2. The design and manufacturing tolerances of thecomponent working parts are very close, therefore,even the smallest amount of dirt or foreign matterentering a system can cause wear or damage to thecomponents and generally results in faulty opera-tion. Every precaution must be taken to keephydraulic oil clean, including reserve oil in storage.Hydraulic system filters should be checked,cleaned, and/or replaced as necessary, at the speci-fied intervals required in the Lubrication Chart inSection 1 and the Preventive Maintenance andInspection Chart in this section. Always examine fil-ters for evidence of metal particles.

3. Cloudy oils indicate a high moisture content whichpermits organic growth, resulting in oxidation or cor-rosion. If this condition occurs, the system must bedrained, flushed, and refilled with clean oil.

4. It is not advisable to mix oils of different brands ortypes, except as recommended, as they may notcontain the same required additives or be of compa-rable viscosities. Good grade mineral oils, with vis-cosities suited to the ambient temperatures in whichthe machine is operating, are recommended for use.

NOTE: Metal particles may appear in the oil or filters of newmachines due to the wear-in of meshing compo-nents.


3121804 – JLG Lift – 2-3

Hydraulic Oil

1. Refer to Section1 for recommendations for viscosityranges.

2. JLG recommends Mobilfluid 424, which has an SAEviscosity of 10W-30 and a viscosity index of 152.

NOTE: Start-up of hydraulic system with oil temperaturesbelow -26°C (-15°F). is not recommended. If it isnecessary to start the system in a sub-zero environ-ment, it will be necessary to heat the oil with a lowdensity, 100VAC heater to a minimum temperatureof -26°C (-15°F).

3. The only exception to the above is to drain and fillthe system with Mobil DTE 11 oil or its equivalent.This will allow start up at temperatures down to -29°C (-20°F ). However, use of this oil will give poor per-formance at temperatures above 49°C (120°F). Sys-tems using DTE 11 oil should not be operated attemperatures above 94°C (200°F). under any condi-tion.

Changing Hydraulic Oil

1. Use of any of the recommended crankcase orhydraulic oils eliminates the need for changing theoil on a regular basis. However, filter elements mustbe changed after the first 50 hours of operation andevery 300 hours thereafter. If it is necessary tochange the oil, use only those oils meeting orexceeding the specifications appearing in this man-ual. If unable to obtain the same type of oil suppliedwith the machine, consult local supplier for assis-tance in selecting the proper equivalent. Avoid mix-ing petroleum and synthetic base oils. JLGIndustries recommends changing the hydraulic oilevery two years.

2. Use every precaution to keep the hydraulic oil clean.If the oil must be poured from the original containerinto another, be sure to clean all possible contami-nants from the service container. Always clean themesh element of the filter and replace the cartridgeany time the system oil is changed.

3. While the unit is shut down, a good preventive main-tenance measure is to make a thorough inspectionof all hydraulic components, lines, fittings, etc., aswell as a functional check of each system, beforeplacing the machine back in service.

Lubrication Specifications

Specified lubricants, as recommended by the componentmanufacturers, are always the best choice, however,multi-purpose greases usually have the qualities whichmeet a variety of single purpose grease requirements.Should any question arise regarding the use of greases inmaintenance stock, consult your local supplier for evalua-tion.

2.4 CYLINDERS - THEORY OF OPERATION

Cylinders are of the double acting type. The Lift and Steersystems incorporate double acting cylinders. A doubleacting cylinder is one that requires oil flow to operate thecylinder rod in both directions. Directing oil (by actuatingthe corresponding control valve to the piston side of thecylinder) forces the piston to travel toward the rod end ofthe barrel, extending the cylinder rod (piston attached torod). When the oil flow is stopped, movement of the rodwill stop. By directing oil to the rod side of the cylinder, thepiston will be forced in the opposite direction and the cyl-inder rod will retract.

A holding valve is used in the Lift circuit to prevent retrac-tion of the cylinder rod should a hydraulic line rupture or aleak develop between the cylinder and its related controlvalve.

2.5 VALVES - THEORY OF OPERATION

Solenoid Control Valves (Bang-Bang)

Control valves used are four-way three-position solenoidvalves of the sliding spool design. When a circuit is acti-vated and the control valve solenoid energizes, the spoolis shifted and the corresponding work port opens to per-mit oil flow to the component in the selected circuit, withthe opposite work port opening to reservoir. Once the cir-cuit is deactivated (control returned to neutral), the valvespool returns to neutral (center) and oil flow is thendirected through the valve body and returns to reservoir. Atypical control valve consists of the valve body, slidingspool, and two solenoid assemblies. The spool ismachine fitted in the bore of the valve body. Lands on thespool divide the bore into various chambers, which, whenthe spool is shifted, align with corresponding ports in thevalve body open to common flow. At the same time otherports would be blocked to flow. The spool is spring-loaded to center position, therefore when the control isreleased, the spool automatically returns to neutral, pro-hibiting any flow through the circuit.


2-4 – JLG Lift – 3121804

Proportional Control Valves

The proportional control valves provide a power outputmatching that required by the load. A small line connectedto a load sensing port feeds load pressure back to asequence valve. The sequence valve senses the differ-ence between the load and pump outlet pressure, andvaries the pump displacement to keep the difference con-stant. This differential pressure is applied across thevalve’s meter-in spool, with the effect that pump flow isdetermined by the degree of spool opening, independentof load pressure. Return lines are connected together,simplifying routing of return flow and to help reduce cavi-tation. Load sensing lines connect through shuttle valvesto feed the highest load signal back to the sequencevalve. Integral actuator port relief valves, anti-cavitationcheck valves, and load check valves are standard.

Relief Valves

Main relief valves are installed at various points within thehydraulic system to protect associated systems and com-ponents against excessive pressure. Excessive pressurecan be developed when a cylinder reaches its limit oftravel and the flow of pressurized fluid continues from thesystem control. The relief valve provides an alternate pathfor the continuing flow from the pump, thus preventingrupture of the cylinder, hydraulic line or fitting. Completefailure of the system pump is also avoided by relieving cir-cuit pressure. The relief valve is installed in the circuitbetween the pump outlet (pressure line) and the cylinderof the circuit, generally as an integral part of the systemvalve bank. Relief pressures are set slightly higher thanthe load requirement, with the valve diverting excesspump delivery back to the reservoir when operating pres-sure of the component is reached.

Crossover Relief Valves

Crossover relief valves are used in circuits where the actu-ator requires an operating pressure lower than that sup-plied to the system. When the circuit is activated and therequired pressure at the actuator is developed, the cross-over relief diverts excess pump flow to the reservoir. Indi-vidual, integral reliefs are provided for each side of thecircuit.

2.6 COMPONENT FUNCTIONAL DESCRIPTION

Hydraulic PumpThe machine is equipped with two hydraulic pumps, afunction pump and a drive pump. The function pump is asingle-section gear pump that controls the lift and steerfunctions and provides a maximum output of 18 lpm (4.75gpm). The drive pump is a single-section piston pump thatcontrols the drive function and provides an output of 83.3lpm (22 gpm).

Lift Cylinder Counterbalance/Manual Descent ValveThe lift cylinder counterbalance/manual descent valve islocated on top of the lift cylinder. The counterbalancevalve is used to hold the platform in place when raised. Acable is connected to the valve which, when pulled, manu-ally opens the lift down port and allows the platform to belowered in the event hydraulic power is lost.

2.7 WEAR PADS

Sliding PadsThe original thickness of the sliding pads is 51 mm (2 in).Replace sliding pads when worn to 48 mm (1.875 in).

2.8 CYLINDER CHECKING PROCEDURES

NOTE: Cylinder checks must be performed any time a cylin-der component is replaced or when improper systemoperation is suspected.

Cylinder w/o Counterbalance Valves - Steer Cylinder

IMPORTANTOPERATE FUNCTIONS FROM GROUND CONTROL STATIONONLY.

DO NOT FULLY EXTEND CYLINDER TO END OF STROKE.RETRACT CYLINDER SLIGHTLY TO AVOID TRAPPING PRES-SURE.

1. Using all applicable safety precautions, activatemotor and fully extend cylinder to be checked. Shutdown motor.

2. Carefully disconnect hydraulic hose from retract portof cylinder. There will be initial weeping of hydraulicfluid which can be caught in a suitable container.After the initial discharge, there should be no furtherleakage from the retract port.


3121804 – JLG Lift – 2-5

3. Activate motor and activate cylinder extend function.Check retract port for leakage.

4. If cylinder leakage is 6-8 drops per minute or more,piston seals are defective and must be replaced. Ifcylinder retract port leakage is less than 6-8 dropsper minute, carefully reconnect hose to retract portand retract cylinder.

5. With cylinder fully retracted, shut down motor andcarefully disconnect hydraulic hose from cylinderextend port.

6. Activate motor and activate cylinder retract function.Check extend port for leakage.

7. If cylinder leakage is 6-8 drops per minute or more,piston seals are defective and must be replaced. Ifextend port leakage is less than 6-8 drops perminute, carefully reconnect hose to extend port,then activate cylinder through one complete cycleand check for leaks.

Cylinders w/Single Counterbalance Valves - Lift Cylinder

IMPORTANTOPERATE ALL FUNCTIONS FROM GROUND CONTROL STATIONONLY.

1. Using all applicable safety precautions, activatehydraulic system.

WHEN WORKING ON THE LIFT CYLINDER, RAISE THE PLAT-FORM COMPLETELY AND SUPPORT THE PLATFORM USING ASUITABLE OVERHEAD LIFTING DEVICE. (EXAMPLE: SEE FIGURE2-1., ARMS AND PLATFORM POSITIONING AND SUPPORT, CYL-INDER REPAIR)

DO NOT FULLY EXTEND LIFT CYLINDER TO END OF STROKE.RETRACT CYLINDER SLIGHTLY TO AVOID TRAPPING PRES-SURE.

2. Raise platform completely then retract cylinderslightly to avoid trapping pressure. Place a suitableoverhead lifting device approximately 2.5 cm (1 in)below the platform.

3. Shut down hydraulic system and allow machine tosit for 10-15 minutes. Carefully remove hydraulichoses from cylinder port block.

4. There will be initial weeping of hydraulic fluid, whichcan be caught in a suitable container. After the initialdischarge, there should not be any further leakagefrom the ports. If leakage continues at a rate of 6-8drops per minute or more, the counterbalance valveis defective and must be replaced.

5. If no repairs are necessary or when repairs havebeen made, carefully reconnect hydraulic hoses tothe appropriate ports.

6. Remove lifting device from platform, activate hydrau-lic system and run cylinder through one completecycle to check for leaks.

2.9 LIFT CYLINDER REMOVAL AND INSTALLATION

Removal

1. Place the machine on a flat and level surface. Startthe motor and raise the platform. Shut down theengine and attach a suitable lifting device to the plat-form.

2. Remove the bolt and locknut securing the cylinderrod attach pin to the upper inner arm assembly.Using a suitable brass drift, drive out the rod endattach pin from the arm assembly.

3. Retract the lift cylinder rod completely.

4. Tag and disconnect the hydraulic lines, then cap thelift cylinder hydraulic lines and ports.

5. Remove the bolt and locknut securing the barrel endattach pin to the lower arm assembly. Using a suit-able brass drift, drive out the barrel end attach pinfrom the arm assembly.

6. Carefully remove the cylinder from the scissor liftand place in a suitable work area.

Installation

1. Install lift cylinder in place using suitable slings,aligning barrel end attach pin mounting holes onlower arm assembly.

2. Using a suitable drift, drive the barrel end attach pinthrough the mounting holes in the lift cylinder andthe lower arm assembly. Secure in place with thebolt and locknut.

3. Remove cylinder port plugs and hydraulic line capsand correctly attach lines to cylinder ports.

4. Extend the cylinder rod until the attach pin holealigns with those in the upper arm assembly. Using asuitable drift, drive the cylinder rod attach pinthrough the aligned holes, taking care to align thepin retaining hole with the hole in arm assembly.Secure the pin in place with the bolt and locknut.

5. Lower platform to stowed position and shut downmotor. Check hydraulic fluid level and adjust accord-ingly.


2-6 – JLG Lift – 3121804

.

Figure 2-1. Arms and Platform Positioning and Support, Cylinder Repair


3121804 – JLG Lift – 2-7

6. Remove the cylinder rod from the holding fixture.

7. Position the cylinder barrel in a suitable holding fix-ture.

IMPORTANTEXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THECYLINDER ROD, HEAD, AND PISTON. AVOID PULLING THE RODOFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTONAND CYLINDER BARREL SURFACES.

8. With barrel clamped securely, and while adequatelysupporting the rod, insert the piston end into thebarrel cylinder. Ensure that the piston loading o-ringand seal ring are not damaged or dislodged.

9. Continue pushing the rod into the barrel until the cyl-inder head gland can be inserted into the barrel cyl-inder.

10. If applicable, secure the cylinder head retainer usinga suitable chain wrench.

11. After the cylinder has been reassembled, the rodshould be pushed all the way in (fully retracted) priorto the reinstallation of any holding valve or valves.

12. If applicable, install the cartridge-type holding valveand fittings in the port block using new o-rings asapplicable.

Figure 2-2. 330CRT Lift Cylinder


2-8 – JLG Lift – 3121804

Figure 2-3. 400CRT LIft Cylinder


3121804 – JLG Lift – 2-9

2.10 LIFT CYLINDER REPAIR

Disassembly

IMPORTANTDISASSEMBLY OF THE CYLINDER SHOULD BE PERFORMED ONA CLEAN WORK SURFACE IN A DIRT FREE WORK AREA.

1. Connect a suitable auxiliary hydraulic power sourceto the cylinder port block fitting.

IMPORTANTDO NOT FULLY EXTEND CYLINDER TO END OF STROKE.RETRACT CYLINDER SLIGHTLY TO AVOID TRAPPING PRES-SURE.

2. Operate the hydraulic power source and extend thecylinder. Shut down and disconnect the powersource. Adequately support the cylinder rod, if nec-essary.

3. If applicable, remove the cartridge-type holdingvalve and fittings from the cylinder port block. Dis-card o-rings.

4. Place the cylinder barrel into a suitable holding fix-ture..

5. Mark cylinder head and barrel with a center punchfor easy realignment. Using an allen wrench, loosen

the cylinder head retainer cap screws, and removecap screws from cylinder barrel.

6. Using a spanner wrench, loosen the end cap orhead retainer, and remove from cylinder barrel.

7. Attach a suitable pulling device to the cylinder rodport block end or cylinder rod end, as applicable.

IMPORTANTEXTREME CARE SHOULD BE TAKEN WHEN REMOVING THE CYL-INDER ROD, HEAD, AND PISTON. AVOID PULLING THE ROD OFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON ANDCYLINDER BARREL SURFACES.

8. With the barrel clamped securely, apply pressure tothe rod pulling device and carefully withdraw thecomplete rod assembly from the cylinder barrel.

9. Using suitable protection, clamp the cylinder rod ina vise or similar holding fixture as close to the pistonas possible.

10. Loosen and remove the cap screw(s), if applicable,which attach the tapered bushing to the piston.

Figure 2-4. Cylinder Barrel Support

Figure 2-5. Capscrew Removal

Figure 2-6. Cylinder Rod Support


2-10 – JLG Lift – 3121804

11. Insert the cap screw(s) in the threaded holes in theouter piece of the tapered bushing. Progressivelytighten the cap screw(s) until the bushing is looseon the piston.

12. Remove the bushing from the piston.

13. Screw the piston CCW, by hand, and remove thepiston from cylinder rod.

14. Remove and discard the piston o-rings, seal rings,and backup rings.

15. Remove piston spacer, if applicable, from the rod.

16. Remove the rod from the holding fixture. Removethe cylinder head gland and retainer plate, if applica-ble. Discard the o-rings, back-up rings, rod seals,and wiper seals.

Cleaning and Inspection

1. Clean all parts thoroughly in an approved cleaningsolvent.

2. Inspect the cylinder rod for scoring, tapering, ovality,or other damage. If necessary, dress rod withScotch Brite or equivalent. Replace rod if necessary.

3. Inspect threaded portion of rod for excessive dam-age. Dress threads as necessary.

4. Inspect inner surface of cylinder barrel tube for scor-ing or other damage. Check inside diameter fortapering or ovality. Replace if necessary.

5. Inspect threaded portion of barrel for damage. Dressthreads as necessary.

6. Inspect piston surface for damage and scoring andfor distortion. Dress piston surface or replace pistonas necessary.

7. Inspect threaded portion of piston for damage.Dress threads as necessary.

8. Inspect seal and o-ring grooves in piston for burrsand sharp edges. Dress applicable surfaces as nec-essary.

9. Inspect cylinder head inside diameter for scoring orother damage and for ovality and tapering. Replaceas necessary.

10. Inspect threaded portion of head for damage. Dressthreads as necessary.

11. Inspect seal and o-ring grooves in head for burrsand sharp edges. Dress applicable surfaces as nec-essary.

12. Inspect cylinder head outside diameter for scoringor other damage and ovality and tapering. Replaceas necessary.

13. If applicable, inspect rod and barrel bearings forsigns of correct excessive wear or damage. Replaceas necessary.

a. Thoroughly clean hole, (steel bushing) of burrs,dirt etc. to facilitate bearing installation.

b. Inspect steel bushing for wear or other damage.If steel bushing is worn or damaged, rod/barrelmust be replaced.

c. Lubricate inside of the steel bushing with WD40prior to bearing installation.

d. Using an arbor of the correct size, carefullypress the bearing into steel bushing.

14. Inspect travel limiting collar or spacer for burrs andsharp edges. If necessary, dress inside diametersurface with Scotch Brite or equivalent.

15. If applicable, inspect port block fittings and holdingvalve. Replace as necessary.

16. Inspect the oil ports for blockage or the presence ofdirt or other foreign material. Repair as necessary.

17. If applicable, inspect piston rings for cracks or otherdamage. Replace as necessary.

Figure 2-7. Tapered Bushing Removal


3121804 – JLG Lift – 2-11

Assembly

NOTE: Prior to cylinder assembly, ensure that the propercylinder seal kit is used. See your JLG Parts Manual.

Apply a light film of hydraulic oil to all componentsprior to assembly.

1. A special tool is used to install a new rod seal intothe applicable cylinder head gland groove.

IMPORTANTWHEN INSTALLING "POLY-PAK" PISTON SEALS, ENSURE SEALSARE INSTALLED PROPERLY. REFER TO WIPER SEAL INSTALLA-TION FOR CORRECT SEAL ORIENTATION. IMPROPER SEALINSTALLATION COULD RESULT IN CYLINDER LEAKAGE ANDIMPROPER CYLINDER OPERATION.

2. Use a soft mallet to tap a new wiper seal into theapplicable cylinder head gland groove. Install a newwear ring into the applicable cylinder head glandgroove.

3. Place a new o-ring and back-up seal in the applica-ble outside diameter groove of the cylinder head.

4. Install washer ring onto rod, carefully install the headgland on the rod, ensuring that the wiper and rodseals are not damaged or dislodged. Push the headalong the rod to the rod end, as applicable.

5. Carefully slide the piston spacer on the rod.

6. If applicable, correctly place new o-ring in the innerpiston diameter groove. (The backup ring side fac-ing the O-ring is grooved.)

7. If applicable, correctly place new seals and guidelock rings in the outer piston diameter groove. (Atube, with I.D. slightly larger than the O.D.of the pis-ton is recommended to install the solid seal.)

Figure 2-8. Rod Seal Installation

Figure 2-9. Wiper Seal Installation

Figure 2-10. Installation of Head Seal Kit


2-12 – JLG Lift – 3121804

NOTE: The backup rings for the solid seal have a radius onone side. This side faces the solid seal.(See magni-fied insert in (See Figure 2-11.))The split of sealsand backup rings are to be positioned so as not to bein alignment with each other.

1. Using suitable protection, clamp the cylinder rod ina vise or similar holding fixture as close to piston aspossible.

2. Carefully thread the piston on the cylinder rod handtight, ensuring that the o-ring and back-up rings arenot damaged or dislodged.

3. Thread piston onto rod until it abuts the spacer endand install the tapered bushing.

NOTE: When installing the tapered bushing, piston and mat-ing end of rod must be free of oil.

4. Assemble the tapered bushing loosely into the pis-ton and insert JLG capscrews (not vendor cap-screws) through the drilled holes in the bushing andinto the tapped holes in the piston.

5. Tighten the capscrews evenly and progressively inrotation to the specified torque value.

6. After the screws have been torqued, tap the taperedbushing with a hammer (16 to 24 oz.) and brassshaft (approximately 3/4" in diameter) as follows;

a. Place the shaft against the cylinder rod and incontact with the bushing in the spaces betweenthe capscrews.

b. Tap each space once; this means the taperedbushing is tapped 3 times as there are 3 spacesbetween the capscrews.

7. Retorque the capscrews evenly and progressively inrotation to the specified torque value.


9. Place new guide locks and seals in the applicableoutside diameter grooves of the cylinder piston.(See Figure 2-11.)

Figure 2-11. Piston Seal Kit Installation

Figure 2-12. Tapered Bushing Installation

Figure 2-13. Seating the Tapered Bearing


3121804 – JLG Lift – 2-13


IMPORTANTEXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THECYLINDER ROD, HEAD, AND PISTON. AVOID PULLING THE RODOFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTONAND CYLINDER BARREL SURFACES.

11. With barrel clamped securely, and while adequatelysupporting the rod, insert the piston end into thebarrel cylinder. Ensure that the piston loading o-ringand seal ring are not damaged or dislodged.

12. Continue pushing the rod into the barrel until the cyl-inder head gland can be inserted into the barrel cyl-inder.

13. Secure the cylinder head gland using the washerring and socket head bolts.

14. After the cylinder has been reassembled, the rodshould be pushed all the way in (fully retracted) priorto the reinstallation of any holding valve or valves.

15. If applicable, install the cartridge-type holding valveand fittings in the rod port block, using new o-ringsas applicable. (See Table 2-1, Cylinder ComponentTorque).

Figure 2-14. Poly-Pak Piston Seal Installlation

Figure 2-15. Rod Assembly Installation

Table 2-1. Cylinder Component Torque

ComponentTorque Value

(w/Loctite)

Tapered Bushing Retaining Screws - Lift Cylinder 80 ft lb(108 Nm)

Head Retaining Screws - Lift Cylinder 9 ft lb(12 Nm)

Table 2-2. Holding Valve Torque Specifications

Description Torque Value

Sun - 7/8 hex M20 x 1.5 thds 30 - 35 ft lb 41 - 48 Nm

Sun - 1-1/8 hex 1 - 14 UNS thds 45 - 50 ft lb 61 - 68 Nm

Sun - 1-1/4 hex M36 x 2 thds 150 - 153 ft lb 204 - 207 Nm

Racine - 1-1/8 hex 1-1/16 - 12 thds 50 - 55 ft lb 68 - 75 Nm




2-14 – JLG Lift – 3121804

2.11 STEER CYLINDER REPAIR

RemovalBefore beginning this procedure, ensure that the parkingbrake is engaged and the rear wheels are chocked.

1. Tag and disconnect the hydraulic lines to the steercylinder, then cap the steer cylinder hydraulic linesand ports.

2. At each steer spindle, remove the bolt and lock nutsecuring the steer cylinder to the spindle.

3. When the steer cylinder is disconnected from thesteer spindles, turn each wheel by hand to giveclearance to remove the steer cylinder from the frontaxle.

4. Carefully lift the steer cylinder until the cylindermounting block clears the mounting slot in the bot-

tom of the axle, then slowly remove the cylinder fromthe axle and place it in a suitable work area.

Disassembly

IMPORTANTDISASSEMBLY OF THE CYLINDER SHOULD BE PERFORMED ONA CLEAN WORK SURFACE IN A DIRT FREE WORK AREA.

1. Place the cylinder barrel into a suitable holding fix-ture.

2. Using a suitable chain wrench, carefully remove thecylinder head retainer from one end of the cylinderbarrel.

3. Attach a suitable pulling device to one end of thecylinder rod.

Figure 2-16. Steer Cylinder Assembly


3121804 – JLG Lift – 2-15

IMPORTANTEXTREME CARE SHOULD BE TAKEN WHEN REMOVING THE CYL-INDER ROD, SPACER, AND PISTON. AVOID PULLING THE RODOFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTONAND CYLINDER BARREL SURFACES.

4. With the barrel clamped securely, apply pressure tothe rod pulling device and carefully withdraw thecomplete rod assembly from the cylinder barrel.

5. Using a suitable chain wrench, carefully remove theremaining cylinder head retainer from the oppositeend of the cylinder barrel. Remove the head andremove and discard the wiper, rod seal, 0-ring andwear ring.

6. Using suitable protection, clamp the cylinder rod ina vise or similar holding fixture.

7. Carefully remove the head from the cylinder rod andremove and discard the wiper, rod seal, o-ring andwear ring.

8. Carefully remove the spacers from the cylinder rod,then remove the retaining rings securing the pistonin place on the cylinder rod. Discard the retainingrings.

9. Carefully remove the piston from the cylinder rod.Remove and discard the T-seal and o-ring.


Cleaning and Inspection

1. Clean all parts thoroughly in an approved cleaningsolvent.

2. Inspect the cylinder rod for scoring, tapering, ovality,or other damage. If necessary, dress the rod withScotch Brite or equivalent. Replace the rod if neces-sary.

3. Inspect the threaded portion of the rod for excessivedamage. Dress the threads as necessary.

4. Inspect the inner surface of the cylinder barrel tubefor scoring or other damage. Check the inside diam-eter for tapering or ovality. Replace the barrel if nec-essary.

5. Inspect the piston surface for damage, scoring anddistortion. Dress the piston surface or replace thepiston as necessary.

6. Inspect the seal and o-ring grooves in the piston forburrs and sharp edges. Dress applicable surfacesas necessary.

7. Inspect the inside diameter of the spacers andheads for scoring or other damage and for ovalityand tapering. Replace as necessary.

8. Inspect the seal and o-ring grooves in the heads forburrs and sharp edges. Dress applicable surfacesas necessary.

9. Inspect the outside diameter of the spacers andheads for scoring or other damage and ovality andtapering. Replace as necessary.

10. Inspect the oil ports for blockage or the presence ofdirt or other foreign material. Repair as necessary.

11. Inspect the cam follower for wear or damage.Replace as necessary.

Assembly

NOTE: Prior to cylinder assembly, ensure that the propercylinder seal kit is used.

Apply a light film of hydraulic oil to all componentsprior to assembly.

1. Using suitable protection, clamp the cylinder rod ina vise or similar holding fixture.

2. Place a new o-ring into the cylinder rod pistongroove.

3. Place a new T-seal on the piston, then carefullyinstall the piston the cylinder rod, ensuring that theo-ring in the rod groove is not damaged or dis-lodged. Secure the piston in place with two newretaining rings.

4. Carefully slide the spacers onto the cylinder rod.

5. Place a new wiper, rod seal, o-ring and wear ring oneach of the two cylinder heads. Set the heads asidefor later installation on the cylinder rod.

6. Remove the cylinder rod assembly from the holdingfixture.


IMPORTANTEXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THECYLINDER ROD, PISTON AND HEADS. AVOID PULLING THE RODOFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTONAND CYLINDER BARREL SURFACES.

8. With the barrel clamped securely, and while ade-quately supporting the cylinder rod assembly, insertthe cylinder rod assembly into the cylinder barrel.Ensure that the piston T-seal and o-ring are not dam-aged or dislodged.

9. Continue pushing the rod assembly into the cylinderbarrel until the cylinder rod is approximately cen-tered in the barrel.


2-16 – JLG Lift – 3121804

10. Carefully install one of the cylinder heads on oneend of the cylinder rod and push the head onto therod until it is snug against the end of the cylinderbarrel.

11. Install one of the cylinder head retainers on the endof the cylinder barrel and tighten with a suitablechain wrench.

12. Carefully install the remaining cylinder head on theopposite end of the cylinder rod and push the headonto the rod until it is snug against the end of thecylinder barrel.

13. Install the remaining cylinder head retainer on theend of the cylinder barrel and tighten with a suitablechain wrench.

Installation

1. Carefully install the steer cylinder assembly into thefront axle. Align the cylinder mounting block on thebarrel with the mounting slot in the bottom of theaxle and lower the steer cylinder until the mountingblock rests in the slot.

2. Turn the steer wheels to line up the mounting holesin the steer spindles and the steer cylinder ends.Secure each end of the steer cylinder with a bolt andlock nut.

3. Reconnect the hydraulic hoses to the applicable cyl-inder ports.

2.12 OSCILLATION CYLINDER BLEEDING

NOTE: Park the machine on a firm and level surface with therear wheels blocked before starting the bleeding pro-cedure.

1. Jack up the front of the machine so that both wheelsare raised enough to allow the axle to fully oscillate.

2. Have a second person start the engine, press andhold the start button until Hi engine is activated.

3. On the side of the axle that is fully raised, loosen thebleeder screw to release any air that may be in thehydraulic line. Continue to bleed until no air bubblesare visible.

4. Tighten the bleeder screw then push the raisedwheel down and repeat the process for the oppositelevel cylinder.

2.13 MAGNETIC SPEED PICKUP CLEANING PROCEDURE

1. Locate the magnetic speed pickup on the bell hous-ing on the right side of the motor.

2. Using an 11/16 wrench, loosen the jam nut and,using your fingers, thread the pickup out of the bellhousing.

3. After cleaning and inspecting the magnetic speedpickup reinstall back into the bell housing.

4. The magnetic speed pickup should be tightened fin-ger tight and then backed out 1/4 turn to properlyset.

NOTE: Flats on the magnetic pickup must be oriented verti-cally.

5. Replace the jam nut and tighten.

Figure 2-17. Magnetic Speed Pickup

Figure 2-18. Magnetic Speed Pickup Removal


3121804 – JLG Lift – 2-17

.

2.14 PRESSURE SETTING PROCEDURES

NOTE: Make all pressure adjustments with the engine oper-ating and the hydraulic oil at normal operating tem-perature. In addition, all functions must be operatedfrom the platform control station in order to achievefull pump speed. It may be necessary to use anassistant to adjust the pressure settings while oper-ating the functions from the platform control station.

Lift Relief Adjustments

1. Install a pressure gauge at gauge port MP, locatedon the front upper right side of the valve body. Theport is identified by a stamping on the valve body.

2. From the platform control station, activate the Lift Upfunction by selecting the lift control switch and posi-tioning the joystick to the up position.

3. Bottom out the Lift Up function and adjust the Lift Uprelief to 159 bar (2300 psi) on the 330CRT and172 bar (2500 psi) on the 400CRT.

4. Remove the pressure gauge from gauge port MP.

Steer Relief Adjustment

1. Install a pressure gauge at gauge port MP2, locatedon the lower right side of the valve body. The port isidentified by a stamping on the valve body.

2. Activate the Steer Right function and check Steerpressure. If necessary, adjust Steer pressure to 110bar (1600 psi).

3. Activate the Steer Left function and check Steerpressure. If necessary, adjust Steer pressure to 179bar (2600 psi).

4. Remove the pressure gauge from gauge port MP2.

MP

Steer LeftSteer Right

Lift

Brake Release

Dump Valve

Actuator for Tow Brake Release

Valve Knob

P2Steer Right Steer Left

LiftMain

Figure 2-19. Valve Components


2-18 – JLG Lift – 3121804

2.15 LIMIT SWITCH ADJUSTMENT

Speed Cutout Switch

The speed cutout switch is located on the right side of theframe of the machine. When activated, the switch cuts outthe high drive function. Adjust the switch to activate whenthe platform is raised above the stowed position.

Drive Cutout Switch (400 CRT)

The drive cutout switch is located on the left side of theframe of the machine. When activated, the switch cuts outthe drive function. Adjust the switch to activate when theplatform is raised to 9.1m (30 ft.).

2.16 AUTOMATIC CHOKE - FIELD ADJUSTMENT (DF-750)

Inspection

NOTE: All automatic choke assemblies have been pre-set tooperate between -7°C and 38°C (20°F and 100°F)with little or no adjustment. If the machine will beoperated for prolong use outside these temperatureranges, adjustments could be made to improve per-formance of the engine.

The machine will take time to warm up and you mayexperience low power or rough running for the firstfew minutes of operation or until the engine warmsup. LET THE ENGINE WARM UP.

Make sure that the choke shaft operates freely and doesnot bind. This can be done without removing the air hornby rotating the bronze coupling with an eraser on a pencilor by removing the vacuum pull off line at the manifoldand supply a small amount of vacuum to the hose. thechoke rod should move freely using either method.

Adjustments

NOTE: If the choke rod is binding make sure the supportbracket is straight

1. There are two adjustments Vertical (loosening the airhorn nuts) and Horizontal (loosening the bracket toadaptor screws). These two adjustments shouldresolve any binding problem.

2. To adjust the choke at 21°C (70°F) ambient, removethe air horn and reinstall the nut that holds the chokeand support bracket securely making sure thechoke moves freely.

3. Loosen the 3 top cover screws and rotate the topcover till the choke butterfly is closed with 1/32 inspace between the plate and the wall of the carbure-tor.

4. If the ambient temperature is less then 21°C (70°F)the top cover counter should be rotated CCW 1mark for every -15°C (5°F) less then 21°C (70°F).

5. If the ambient temperature is more then 21°C (70°F)the top cover counter should be rotated CW 1 markfor every -15°C (5°F) less then 21°C (70°F).

.

Reassembly

Reassemble the air horn making sure the choke is notbinding, test to insure that none of the settings havemoved and the choke is not binding.

The vacuum pull off should be set such that when vacuumis applied to the choke system the choke butterfly is fullopen.

NOTE: If the machine starts and stalls immediately or if it isextremely cold, limiting the choke pull off to 75% to90% may improve the performance of the machine.No adjustment is normally required.

Figure 2-20. Automatic Choke Adjustment (DF-750)


3121804 – JLG Lift – 2-19

Diesel Engine

NOTE: Never run the fuel tank dry. Diesel engines cannotbe restarted after running out of fuel until the fuelsystem has been air-vented or ‘bled’ of air. See theKubota Instruction Manual for the proper procedure.

2.17 ELECTRONIC CONTROL SYSTEM

To Connect the Hand Held Analyzer:

1. Connect the four pin end of the cable supplied withthe analyzer, to the top connection of the motor con-troller and connect the remaining end of the cable tothe analyzer.

NOTE: The cable has a four pin connector at each end ofthe cable; the cable cannot be connected back-wards.

2. Power up the Control System by turning the lowerkey to the platform position and pulling both emer-gency stop buttons on.

Using the Analyzer:With the machine power on and the analyzer connectedproperly, the analyzer will display the following:

HELP:

PRESS ENTER

At this point, using the RIGHT and LEFT arrow keys, youcan move between the top level menu items. To select adisplayed menu item, press ENTER. To cancel a selectedmenu item, press ESC; then you will be able to scrollusing the right and left arrow keys to select a differentmenu item.

The top level menus are as follows:

HELP

DIAGNOSTICS

ACTIVATE TESTS

ACCESS LEVEL

PERSONALITIES

MACHINE SETUP

LEVEL VEHICLE

If you press ENTER, at the HELP:PRESS ENTER display,and a fault is present during power up, the analyzer dis-play will scroll the fault across the screen. If there was nofault detected during power up, the display will read:HELP: EVERYTHING OK

If ENTER is pressed again, the display moves to the fol-lowing display:

LOGGED HELP

1: STARTUP (2/1)

At this point, the analyzer will display the current fault, ifany are present. You may scroll through the fault logs toview what the last fifteen faults were. Use the right and leftarrow keys to scroll through the fault logs. To return to thebeginning, press ESC two times.

When a top level menu is selected, a new set of menuitems may be offered; for example:

PLATFORM

DRIVE

LIFT SEL

SPEED SEL

HORN

ENGINE START

FUEL/GLOW

STEER LEFT

STEER RIGHT

JOYSTICK

Pressing ENTER with any of the above displayed menus,will display additional sub-menus within the selectedmenu. In some cases the next level is the parameter orinformation to be changed. Refer to the flow chart for whatmenus are available within the top level menus. You mayonly view the personality settings for selected menuswhile in access level 2. Remember, you may always can-cel a selected menu item by pressing the ESC key.


2-20 – JLG Lift – 3121804

Changing the Access Level of the Hand Held Analyzer:

When the analyzer is first connected, you will be in accesslevel 2 which enables you to only view most configurationsettings which cannot be changed until you enter a pass-word to advance to a lower level. This ensures that a set-ting cannot be accidentally altered. To change the accesslevel, the correct password must be entered. To enter thepassword, scroll to the ACCESS LEVEL menu. For exam-ple:

MENU:

ACCESS LEVEL 2

Press ENTER to select the ACCESS LEVEL menu.

Using the UP or DOWN arrow keys, enter the first digit ofthe password, 3.

Then using the RIGHT arrow key, position the cursor tothe right one space to enter the second digit of the pass-word.

Use the UP or DOWN arrow key to enter the second digitof the password which is 3.

Repeat this process until you have entered all five digits ofthe password which is 33271.

Once the correct password is displayed, press ENTER.

The access level should display the following, if the pass-word was entered correctly:

MENU:

ACCESS LEVEL 1

Repeat the above steps if the correct access level is notdisplayed or you can not adjust the personality settings.

When a machine digit item is selected, press the UP orDOWN arrow keys to adjust its value, for example:

GROUND ALARM:

2=DRIVE

The effect of the machine digit value is displayed alongwith its value. The above display would be selected if themachine was equipped with a ground alarm and youwanted it to sound when driving. There are certain set-tings allowed to install optional features or select themachine model.

When selecting the machine model to match the size ofthe machine, the personality settings will all default to thefactory recommended settings.

NOTE: Refer to the appropriate Machine Personality Set-tings Table, and the Machine Setup Table in the JLGService Manual for the recommended factory set-tings.

Password 33271 will give you access to level 1,which will permit you to change all machine person-ality settings.

CHANGING THESE SETTINGS MAY ADVERSELY AFFECT THEPERFORMANCE OF YOUR MACHINE.

IMPORTANTIT IS A GOOD PRACTICE TO AVOID PRESSURE-WASHING ELEC-TRICAL/ELECTRONIC COMPONENTS. SHOULD PRESSURE-WASHING BE UTILIZED TO WASH AREAS CONTAINING ELECTRI-CAL/ELECTRONIC COMPONENTS, JLG INDUSTRIES, INC. REC-OMMENDS A MAXIMUM PRESSURE OF 750 PSI (52 BAR) AT AMINIMUM DISTANCE OF 12 INCHES (30.5 CM) AWAY FROM THESECOMPONENTS. IF ELECTRICAL/ELECTRONIC COMPONENTSARE SPRAYED, SPRAYING MUST NOT BE DIRECT AND BE FORBRIEF TIME PERIODS TO AVOID HEAVY SATURATION.


3121804 – JLG Lift – 2-21

2.18 FLASH CODES AND DESCRIPTIONS

Table 2-3. Help Messages and Flash Codes

FLASH CODE HELP MESSAGE AND DESCRIPTION

No Flash Code ALARM SOUNDING - TILTED & ABOVE ELEVATIONPlatform is elevated and the chassis is not level.

DIFFERENT FUNCTION SELECTED & IGNOREDA function (i.e. Drive, Lift, etc.) is active and the operator has selected another function. The system has ignored the new selec-tion.

DRIVING AT CUTBACK - ABOVE ELEVATIONPlatform is elevated and the machine is in the drive mode of operation.

FUNCTION SELECTED BUT TRIGGER SWITCH OPENA function (i.e. Drive, Lift, etc.) has been selected by the operator, but the trigger switch is not active (closed).

JOYSTICK MOVED BUT NO FUNCTION SELECTEDThe joystick was moved out of the center position before a function was selected.

2-1 STARTUPA new system power up has occurred since the last help message.

2-2 FUNCTIONS LOCKED OUT - SHORT TO PLATFORM ROW INPUT DETECTED Battery power has been detected on a row input (pins J1-8, J1-9, or J1-13).

FUNCTION PROBLEM - DRIVE PERMANENTLY SELECTEDDrive select switch in the platform control box closed at start up or for more than ten seconds. Release switch to clear fault.

FUNCTION PROBLEM - LIFT PERMANENTLY SELECTEDLift select switch in the platform control box closed at start up or for more than ten seconds. Release switch to clear fault

FUNCTION PROBLEM - O/R PERMANENTLY SELECTEDAn outrigger select switch in the platform control box closed at start up or for more than ten seconds. Release switch to clear fault

FUNCTION PROBLEM - START PERMANENTLY SELECTEDStart switch in the platform control box closed at start up. Release switch to clear fault

FUNCTION PROBLEM - GLOW PLUG PERMANENTLY SELECTEDGlow plug switch in the platform control box closed at start up. Release switch to clear fault

FUNCTION PROBLEM - STEER LEFT PERMANENTLY SELECTEDSteer left switch in the platform control box closed at start up. Release switch to clear fault

FUNCTION PROBLEM - STEER RIGHT PERMANENTLY SELECTEDSteer right switch in the platform control box closed at start up. Release switch to clear fault

JOYSTICK FAULTY - WIPER OUT OF RANGEThe joystick wiper signal input is outside the acceptable voltage range. The wiper wire being off, the wiper wire shorted to battery power, or the wiper wire shorted to battery negative could cause this.

JOYSTICK FAULTY - STEER SWITCHES ACTIVE TOGETHERBoth the steer left and steer right inputs are closed at the same time. A short in the steer switch wiring or a failed steer switch can cause this.

FUNCTION LOCKED OUT - JOYSTICK NOT CENTEREDSelected function is not allowed because the joystick is not centered. Return joystick to center and reselect function.

FUNCTION PROBLEM - TRIGGER PERMANENTLY CLOSEDTrigger switch in the platform control box closed at start up. Release switch to clear fault.

TRIGGER CLOSED TOO LONG WHILE IN NEUTRALTrigger switch in the platform control box closed for more than ten seconds while the joystick is in the neutral position. Release switch to clear fault.

2-3 FUNCTION PROBLEM - LIFT PERMANENTLY SELECTEDLift switch (up or down) in the ground control box closed at start up. Release switch to clear fault


2-22 – JLG Lift – 3121804

FUNCTION PROBLEM - START PERMANENTLY SELECTEDStart switch in the ground control box closed at start up. Release switch to clear fault

FUNCTION PROBLEM - GLOW PLUG PERMANENTLY SELECTEDGlow plug switch in the ground control box closed at start up. Release switch to clear fault

NO DATA FROM TILT SENSOR - NOT CONNECTED OR FAULTYNo signal from the tilt switch. Check wiring and plug connections at the level sensor and at the ground control board.

4-4 BATTERY VOLTAGE TOO LOWBattery voltage below 8.0V. Check battery and alternator.

BATTERY VOLTAGE TOO HIGHBattery voltage above 16V. Check battery and alternator.

5-5 ENGINE SHUTDOWN – OVERSPEEDThe engine speed exceeded 4500 RPM for more than 2 seconds. Check throttle actuator for debris or interference, which pre-vents free movement of actuator. Recycle power to clear the fault and restart.

ENGINE SHUTDOWN - OIL PRES / COOLANT TEMPThe engine oil pressure was too low or the engine coolant temperature was too high for more than 10 seconds. Check engine fluid levels. Recycle power to clear fault and restart.

Table 2-3. Help Messages and Flash Codes


3121804 – JLG Lift – 2-23

(Pre

ss E

scap

e Tw

ice

to R

etur

n to

Hel

p)

*(O

utrig

ger

Opt

ion

Onl

y)

*(Te

st in

Gro

und

Mod

e)

**(D

iese

l Eng

ine

Onl

y)

*(Te

st in

Pla

tform

Mod

e)**

(Due

l Fue

l Eng

ine

Onl

y)**

*(D

iese

l Eng

ine

Onl

y)**

**(O

utrig

ger

Opt

ion

Onl

y)

*(Te

st in

Pla

tform

Mod

e)**

(Out

rigg

er O

ptio

n O

nly)

*(Te

st in

Pla

tform

Mod

e)

*(O

utrig

ger

Opt

ion

Onl

y)

*(O

utrig

ger

Opt

ion

Onl

y)

*(O

utrig

ger

Opt

ion

Onl

y)

Fig

ure

2-21

. A

naly

zer

Flo

w C

har

t - S

hee

t 1 o

f 2


2-24 – JLG Lift – 3121804

BY

PR

ES

SIN

G T

HE

SE

AR

RO

W K

EY

S (

) Y

OU

CA

N S

CR

OLL

TH

RO

UG

H T

HE

TO

P L

EV

EL

ME

NU

S.

��7R

S

�/

H

Y

H

O�0

H

Q

X

��6

X

E

�/

H

Y

H

O�0

H

Q

X

��,WH

P

�WR

�E

H

�9

LH

Z

H

G

��R

U�&

K

D

Q

J

H

G

(Pro

mp

t bef

ore

Cal

ibra

tion)

(Sho

wn

Aft

er C

alib

ratio

n)(S

how

n If

Sen

sor

Not

Det

ecte

d)

(Sho

wn

If m

ore

than

5°

Ou

t o

f Lev

el D

urin

g C

alib

ratio

n)

Fig

ure

2-22

. A

naly

zer

Flo

w C

har

t - S

hee

t 2 o

f 2


3121804 – JLG Lift – 2-25

Table 2-4. Machine Model Adjustment

Adjustment Adjustment range Default Values - Gas Default Values - Diesel

DRIVE

Accel 1.0 to 5.0 sec 4 4

Decel 1.0 to 5.0 sec 2 2

FWD MIN 0 to 100% 21 21

FWD MAX 0 to 100% 48 48

FWD ELEV 0 to 35% 30 30

REV MIN 0 to 100% 21 21

REV MAX 0 to 100% 52 52

REV ELEV 0 to 35% 30 30

LO MAX 35 to 65% 50 50

ENGINE SPD 2800 to 3800 RPM 3600 3000

GAIN 0 to 999 180 50

DROOP 0 to 999 200 250

STABILITY 0 to 999 170 125

LIFT

Accel 0.2 TO 5.0 4 4

Decel 0.2 TO 5.0 0.5 0.5

UP MIN ENG 1400 TO 2200 RPM 2000 2000

UP MAX ENG 2600 to 3600 RPM 3000 3000

LO MAX 35 to 55% 50 50

GAIN 0 to 999 150 10

DROOP 0 to 999 220 240


IDLE

ENGINE SPEED 1200 TO 1500 rpm 1500 1500

GAIN 0 to 999 150 10

DROOP 0 to 999 250 85


MIN ACT 0 T0 100% 19 25

MAX ACT L/D 0 T0 100% 60 100

MAX ACT IDLE 0 T0 100% 55 40

CUT ACT 200 TO 2800 RPM 500 500


2-26 – JLG Lift – 3121804

NOTE: When configuring a CRT scissors machine, themachine configuration must be completed beforeany personality settings can be changed. Changingthe personality settings first and then changing themodel number of the machine configuration willcause the personality settings to return to defaultvalues.

Table 2-5. Machine Configuration Programming Information

Configuration Digit Number Description Default Num-ber

1(Model #)

123

260 CRT330 CRT400 CRT

0

2(Engine Selection)

012

750 Dual Fuel905 Diesel1105 Diesel

0

3(Tilt)

01

No CutoutCutout lift up and drive if tilted and elevated. Required for AUS and BRZ markets

0

4(Drive Cutout)

01

No drive cutout switch installed.Cuts out drive when deck is elevated above a predetermined elevation

(Default for 400 CRT)

0

5(Control Direction)

01

FWD & LIFT upFWD & LIFT dn (for future use)

0

6(Leveling Jacks)

01

NoYes

0


3121804 – JLG Lift – 2-27

2.19 PREVENTIVE MAINTENANCE AND INSPECTION SCHEDULE

The preventive maintenance and inspection checks arelisted and defined in the following table. This table isdivided into two basic parts, the “AREA” to be inspectedand the “INTERVAL” at which the inspection is to takeplace. Under the “AREA” portion of the table, the varioussystems along with the components that make up thatsystem are listed. The “INTERVAL” portion of the table isdivided into five columns representing the various inspec-tion time periods. The numbers listed within the intervalcolumn represent the applicable inspection code forwhich that component is to be checked.

The checks and services listed in this schedule are notintended to replace any local or regional regulations thatmay pertain to this type of equipment nor should the listsbe considered as all inclusive. Variances in interval timesmay occur due to climate and/or conditions and depend-ing on the location and use of the machine.

JLG Industries requires that a complete annual inspectionbe performed in accordance with the “Annual MachineInspection Report” form. Forms are supplied with eachnew machine and are also available from JLG CustomerService. Form must be completed and returned to JLGIndustries.

IMPORTANTJLG INDUSTRIES REQUIRES THAT A COMPLETE ANNUALINSPECTION BE PERFORMED IN ACCORDANCE WITH THE“ANNUAL MACHINE INSPECTION REPORT” FORM.

NOTE: This machine requires periodic safety and mainte-nance inspections be a JLG Dealer.

The inspection and maintenance code numbers are as fol-lows:

1. Check for proper and secure installation.

2. Check for visible damage and legibility.

3. Check for proper fluid level.

4. Check for any structural damage; cracked or brokenwelds; bent or warped surfaces.

5. Check for leakage.

6. Check for presence of excessive dirt or foreignmaterial.

7. Check for proper operation and freedom of move-ment.

8. Check for excessive wear or damage.

9. Check for proper tightness and adjustment.

10. Drain, clean and refill.

11. Check for proper operation while pump/motor isrunning.

12. Check for proper lubrication.

13. Check for evidence of scratches, nicks or rust andfor straightness of rod.

14. Check for condition of element; replace as neces-sary.

15. Check for proper inflation.


2-28 – JLG Lift – 3121804

Table 2-6. Preventive Maintenance and Safety Inspection

AREA INTERVAL

10Hours(Daily)

50 Hours(Weekly)

200 Hours(Monthly)

500 Hours(3 Month)

1000 Hours(6 Month)

PLATFORM

1. Controller 1,11

2. Switches 1,11

3. Placards and Decals 1,2

4. Control Tags 1,2

5. Hoses and Cables 4,8

6. Wear Pads 8

7. Handrails and Chains 1,4

CHASSIS

1. Engine Oil 3 5

2. Battery 3 5

3. Air Cleaner 1 14

4. Exhaust System 1 1,5

5. Engine Mounts 1

6. Hydraulic Pump 1 5

7. Valves 1 5

8. Hydraulic Filter (See Lubrication Chart) 5,14

9. Hydraulic Hoses and Tubing 1 5

10. Hydraulic Oil Tank* 3 5 4

11. Hydraulic Tank Breather 6,14

12. Fuel Tank 3,5 4

13. Lift Cylinder 1,12 5,6,13 4

14. Limit Switch 1,7

15. Tilt Alarm Switch 1,7

16. Placards and Decals 1,2

17. Wheel and Tire Assemblies 1 8,9

18. Drive Motors 1,5,6

19. Drive Brakes 1,6 8

20. Drive Torque Hubs 1,3,5,6

21. Steer Cylinder 1 5,6,13 4

22. Steer Components 1 4,6 8

23. Wheel Bearings (2 Wheel Drive) 8 12

24. Sizzor Arms 1,4

25. Safety Props 1,4

26. Sliding Wear Pads 8

27. Pivot Pins/Bolts 1,4 7,8

28. Switches, Ground Control 1,11

29. Control Tags 1,2

* Inspection and Maintenance code 10 to be performed annually


3121804 – JLG Lift – 3-1

SECTION 3. TROUBLESHOOTING

3.1 GENERALThis section contains troubleshooting information to beused for locating and correcting most of the operatingproblems which may develop in the aerial platform. If aproblem should develop which is not presented in thissection or which is not corrected by listed correctiveactions, technically qualified guidance should be obtainedbefore proceeding with any maintenance.

Troubleshooting and maintenance information pertainingto the prime mover (engine/motor) that are not containedin this manual are contained in the applicable enginemaintenance manual.

3.2 TROUBLESHOOTING INFORMATIONThe troubleshooting procedures applicable to the aerialplatform are listed and defined in Tables 3-1 through 3-4.As an aid to table use, the platform sizzor is divided into 4major groups, each covered separately within this section.These groups are as follows: Platform, chassis, hydraulicsystem and electrical system.

Each malfunction within an individual group or system isfollowed by a listing of probable causes which will enabledetermination of the applicable remedial action. The prob-able causes and remedial action should, where possible,be checked in the order listed in the tables.

It should be noted that there is no substitute for a thor-ough knowledge of the equipment and related systems.

It should be recognized that the majority of the problemsarising in the machine will be centered in the hydraulicand electrical systems. For this reason, every effort hasbeen made to ensure that all likely problems in theseareas are given the fullest possible treatment. In theremaining machine groups, only those problems whichhave more than one probable cause and remedy areincluded. This means that problems for which the proba-ble cause and remedy may be immediately obvious arenot listed in this section.

The first rule for troubleshooting any circuit that is hydrau-lically operated and electrically controlled is to determineif the circuit is lacking hydraulic oil and electrical power.This can be ascertained by overriding the bypass valve(mechanically or electrically) so that oil is available to thefunction valve, then overriding the function valve mechani-cally. If the function performs satisfactorily, the problemexists with the control circuit.

3.3 HYDRAULIC CIRCUIT CHECKS

The first reference for improper function of a hydraulic sys-tem, where the cause is not immediately apparent, shouldbe the troubleshooting chart. The best place to begin theproblem analysis is at the power source (pump) Once it isdetermined that the pump is serviceable, then a system-atic check of the circuit components, beginning with thecontrol, would follow. For aid in troubleshooting, refer tothe Illustrated Parts Manual for hydraulic diagram of thevarious circuits.


3-2 – JLG Lift – 3121804

.

Table 3-1. Elevation System Troubleshooting

TROUBLE PROBABLE CAUSE REMEDY

Platform Elevation System

No Response to LIft Control

Lift not performed within three seconds after lift function switch is selected.

Reselect lift function switch, then activate joystick within three seconds.

Lift control switch inoperative. Repair or replace control switch.

Hydraulic system oil low. Replenish oil as necessary.

Restricted or broken supply line on valve bank or pump.

Clean, repair or replace line.

Control valve not functioning properly. Repair or replace valve.

Lift cylinder not functioning properly. Repair or replace cylinder.

Hydraulic pump not functioning properly. Repair or replace pump.

Platform will not raise.

Joystick not activated within three sec-onds after lift switch is activated.

Activate lift switch, then activate joystick within three seconds.

Load capacity exceeded. (Personnel and/or equipment on platform).

Reduce load. (Refer to capacity placard).


Restricted or broken hydraulic line or fit-ting.

Clean, repair, or replace line or fitting.


Lift cylinder not functioning properly. Repair or replace lift cylinder.

Engine does not respond when lift control switch is moved to up position.

Refer to Electrical System Troubleshoot-ing - No response to control switch.

No electrical signal being sent to lift up control valve cartridge.

Refer to Electrical System Troubleshooting - No response to control switch.

Platform will not lower

Joystick not activated within three sec. after lift switch is activated.

Depress lift switch, then activate control-ler within three seconds.

No electrical signal sent to lift down con-trol valve cartridge.

Refer to Electrical System Troubleshoot- ing - No response to control switch.

Lift down control valve cartridge not functioning properly.

Repair or replace lift down control valve cartridge.


Engine does not respond when lift switch is moved to down position.

Refer to Electrical System Troubleshoot ing - No response to control switch.

No electrical signal being sent to lift down control valve.

Refer to Electrical System Troubleshoot ing - No response to control switch.

Platform raises and lowers erratically





3121804 – JLG Lift – 3-3

Counterbalance valve on lift cyl. improp- rely adjusted or not functioning properly.

Replace valve.


Worn seals in lift cylinder. Replace seals.


Platform drifts down

Manual lowering valve not functioning properly.

Repair or replace valve.

Worn seals in lift cylinder. Replace seals.

Holding valve on lift cylinder not function-ing properly.

Repair or replace valve.

High Drive does not operate below horizontal

Damaged wiring on limit switch. Repair or replace wiring.

Damaged limit switch. Replace limit switch

Table 3-1. Elevation System Troubleshooting



3-4 – JLG Lift – 3121804

Table 3-2. Chassis Troubleshooting


Drive System

No response to drive controller

Joystick not activated within three sec-onds after drive select switch is activated.

Activate drive select switch, then activate joystick within three seconds.


Hydraulic pump not functioning properly. Repair or replace pump.

Restricted or broken pump supply line. Clean, repair or replace line.

Drive motor not functioning properly. Repair or replace motor.

Damaged wiring on drive controller. Repair or replace wiring.

Drive controller not functioning properly. Repair or replace controller.

Drive brake not releasing. Determine cause and repair or replace brake.

Machine drives erratically

Microcircuit on controller improperly adjusted.

Adjust microswitch on controller for proper operation.

Machine will not travel forward

Joystick not activated within three sec-onds after drive switch is activated.

Activate drive switch, then activate joy-stick within three seconds.



Clean, repair or replace line or fitting.


Drive motor not functioning properly. Repair or replace motor.

Brake not functioning properly. Repair or replace brake.

Engine will not respond when enable switch is activated and drive controller is activated.


No electrical signal being sent to the drive valve cartridge.


Machine will not travel in reverse

See: Machine will not travel forward.

High-Speed Drive function does not operate


3121804 – JLG Lift – 3-5

Loose or damaged wiring between drive controller and High Speed switch.

Ensure proper connection of wires. Using suitable test meter, perform continuity test on wiring between switches. Repair or replace wires as necessary.

Defective high speed control switch. Replace high speed control switch.

Loose or damaged wiring in control box wire harness.

Ensure proper connection of wires at the control switch. Using suitable test meter, perform continuity test on wires. Repair or replace harness as necessary.

Loose or damaged wiring between plat-form and high speed solenoid.

Ensure proper connection of wires at the platform and at the high speed solenoid. Using suitable test meter, perform conti-nuity test on wires. Repair or replace wires as necessary.

High speed solenoid not functioning properly.

Replace solenoid.

Loose or damaged wiring between high speed relay and high speed limit switch.

Ensure proper connection of wires between high speed relay and high speed limit switch. Using suitable test meter, per-form continuity test on wires. Repair or replace wires as necessary.

High speed limit switch not functioning properly.

Repair or replace limit switch.

Loose or damaged wiring in valve wiring harness.

Ensure proper connection of wires at ter-minal strip. Using suitable test meter, per-form continuity test on wires. Repair or replace wires as necessary.

Steering System

No response to steer control switch on controller

Steer switch on controller not functioning properly.

Repair or replace switch.


Hydraulic system pressure too low. Adjust pressure.

Loose or damaged wiring on control switch or solenoid valve.

Ensure proper connection of wires at con-trol switch or solenoid valve. Using suit-able test meter, perform continuity test on wires. Repair or replace wires as neces-sary.

Restricted or broken hydraulic line on valve bank or hydraulic pump.



Steer cylinder not functioning properly. Repair or replace cylinder.

Machine hard to steer or steering is erratic



Clean, repair or replace line or fitting.




3-6 – JLG Lift – 3121804

Machine hard to steer or steering is erratic (cont.)

Lack of lubrication on steer components. Lubricate steer components in accor-dance with Lubrication Chart.

Restricted crossover relief valve. Clean or replace valve.

Steer system pressure low. Adjust pressure.

Bent steering linkage. Repair or replace linkage as required.

Hydraulic pump not functioning properly. Repair or replace valve.


Steering inoperative


Repair or replace switch.

Hydraulic system pressure too low. Adjust pressure.

Loose or damaged wiring on control switch or solenoid valve.

Ensure proper connection of wires at con-trol switch or solenoid valve. Using suit-able test meter, perform continuity test on wires. Repair or replace wires as neces-sary.

Solenoid valve not functioning properly. Repair or replace valve.

Restricted or broken hydraulic line on valve bank or hydraulic pump.


Relief valve improperly set or not function-ing properly.

Reset, repair or replace valve as neces-sary.


Machine will not steer left or right


Replace controller.

Wiring on steer control switch is dam-aged.

Repair or replace wiring.

Wiring on solenoid valve damaged. Repair or replace wiring.

Coil in solenoid damaged. Replace coil.

Bent cylinder rod. Repair or replace cylinder.

Damaged steer linkage. Repair or replace steer linkage.

Machine wanders; steering not firm

Crossover relief valve set too low or not functioning properly.

Reset, repair or replace valve as neces-sary.

Steer linkage loose. Tighten linkage.

Spindle bushings badly worn. Replace bushings.




3121804 – JLG Lift – 3-7

Table 3-3. Hydraulic System Troubleshooting


Hydraulic pump noisy

Air entering system through broken line or fitting Repair or replace line or fitting

Air bubbles in oil Replenish oil as required

Faulty pump coupler Replace coupler

Defective pump bearing Repair or replace pump

Oil filter(s) dirty Clean and/or replace filter(s) as necessary

Pump cavitating (Vacuum in pump due to oil star-vation

Restricted suction line Clean, repair, or replace line

OIl in reserve low Replenish oil to proper level

Restricted reservoir air vent Clean vent

Oil viscosity to high Drain system and replace with recommended oil (Refer to hydraulic oils)

Leak in suction line or manifold Repair or replace line or manifold as necessary

System overheating

Oil viscosity too high Drain system and replace with recommended oil (Refer to hydraulic oils)

Restricted or blocked hydraulic line Repair or replace line

Machine overloaded Check weight in platform

Main relief valve set too high Reset valve as required

Hydraulic system oil low Replenish oil as necessary

Pump not delivering oil

Restricted suction line Clean repair or replace line

Air entering system through broken line or fitting (suction side)

Replace or repair line or fitting

Oil level too low Replenish oil to proper level

Plugged strainer in tank Clean strainer

Pump coupling defective Replace pump coupling

Broken pump drive shaft Repair or replace pump

System pressure too low

Main relief valve set too low Reset valve as required

Main relief valve stuck in open position Clean, repair or replace valve (Check system oil for contamination)

Hydraulic pump not functioning properly Repair or replace pump

Leak in component, line or fitting Repair or replace component, line or fitting

Scored valve spool; Scored cylinder Replace valve; Replace cylinder

System(s) operate erratically

Sticking or binding valve spools, piston rod, etc Clean, repair or replace components as required

Hydraulic oil not a t optimum operating tempera-ture

Allow oil sufficient time to warm up

Pump drive slipping Repair or replace drive


3-8 – JLG Lift – 3121804

Table 3-4. Electrical System Troubleshooting


HAND CONTROLLER

Regardless of which way handle is moved, only one function occurs

Improper or loose wiring to the solenoid(s) Check all wiring for proper connections

Directional valve stuck in one direction Repair or replace valve

Valve will not function when handle is moved in either direction

Joystick not activated within the 3 seconds after function switch was depressed

Reactivate function switch

No electrical power to handle Check electrical input to hand controller (12V)

No electrical power to valve Check electrical output of printed circuit board and electrical signal at the valve

Improper ground Check for proper grounding of handle

Defective controller Repair or replace controller

Microswitches on controller bad or need adjust-ment

Adjust or replace switches

CONTROL SWITCHES

No response to a function control switch

Emergency stop switch not positioned properly Place emergency stop switch to on

Platform/Ground select switch not positioned properly

Place switch to platform or ground, as necessary

Circuit breaker open Determine and correct cause. Reset circuit breaker

No voltage present at emergency stop switch Check battery cable from battery to emergency stop switch for proper connection or damage. Repair or replace cable as necessary

Emergency stop switch not functioning properly Replace switch

No voltage supplied to start relay from emergency stop switch

Check battery cable from switch to relay for proper connection or damage. Repair or replace cable as necessary

No voltage input at terminal strip Check wire from battery to terminal strip for proper connection or damage. Repair or replace cable as necessary

No voltage present at circuit breaker Check wire from terminal strip to battery for proper connection or damage. Repair or replace cable as necessary

Defective circuit breaker Replace circuit breaker

No voltage present at Platform/Ground select switch

Unplug ground control box harness from platform receptacle. check wire from applicable pin in plug to control box power switch for proper connection. Using suitable test meter, perform continuity test on wire. Repair or replace harness as necessary

Defective Platform/Ground select switch Replace Platform/Ground select switch


3121804 – JLG Lift – 3-9

No voltage present at function control switch Check wiring from power switch to function control switch for proper connection or damage. Repair or replace wiring as necessary

Defective function control switch Replace function control switch

No voltage present at applicable control valve coil Check applicable wire for proper connection at terminal strip, valve harness plug pin, valve har-ness receptacle pin and valve coil. Using suitable test meter, perform continuity test on wire. Repair or replace harness as necessary

No voltage supplied to motor from start relay Check battery cable from relay to motor for proper connection or damage. Repair or replace cable as necessary

Defective motor/pump assembly Replace motor/pump assembly

ENGINE STARTER SYSTEM

Engine will not crank

Discharged battery or loose battery terminals Check and charge battery or replace battery as necessary. Clean and secure battery terminals

Starter relay faulty or faulty relay connections Using a test meter, check relay coil terminals for presence of electrical power and for energization of relay coil. Also check relay terminals for correct switching of contacts. Replace relay as necessary

Malfunctioning starter solenoid or motor Replace solenoid or motor in accordance with applicable manufacturer’s manual

Defective start lockout solenoid Replace start lockout solenoid

Malfunctioning ignition switch Using a test meter, check ignition switch for cor-rect switching of contacts. replace switch as nec-essary

Faulty ignition and/or starter circuit wiring Check wiring continuity. refer to wiring diagram

Defective ring gear or flywheel Replace ring gear

INSTRUMENTS AND INDICATORS

Ammeter inoperative

Damaged wiring in circuits Repair or replace wiring

Ammeter not functioning properly Replace ammeter

Alternator not charging Repair or replace alternator

Travel warning horn inoperative

Circuit breaker open Determine and correct cause

Damaged wiring in horn circuit Replace horn

Hourmeter inoperative

Damaged wiring in hourmeter circuit Repair or replace wiring

Inoperative hourmeter Replace hourmeter

Table 3-4. Electrical System Troubleshooting



3-10 – JLG Lift – 3121804

GROUNDELECTRONICS

Figure 3-1. Electrical Schematic - Sheet 1 of 2


3121804 – JLG Lift – 3-11

GROUNDELECTRONICS

1870118_I

Figure 3-2. Electrical Schematic - Sheet 2 of 2


3-12 – JLG Lift – 3121804

Figure 3-3. Hydraulic Schematic - Sheet 1 of 2


3121804 – JLG Lift – 3-13

2792397 E

Figure 3-4. Hydraulic Schematic - Sheet 2 of 2


3-14 – JLG Lift – 3121804

This page intentionally left blank.

JLG Worldwide Locations

Corporate Office

JLG Industries, Inc.

1 JLG Drive

McConnellsburg PA. 17233-9533

USA

Phone: (717) 485-5161

Fax: (717) 485-6417

JLG Industries (Australia)P.O. Box 511911 Bolwarra RoadPort MacquarieN.S.W. 2444AustraliaPhone: (61) 2 65 811111Fax: (61) 2 65 810122

JLG Industries (UK)Unit 12, SouthsideBredbury Park Industrial EstateBredburyStockportSK6 2sPEnglandPhone: (44) 870 200 7700Fax: (44) 870 200 7711

JLG Deutschland GmbHMax Planck Strasse 21D-27721 Ritterhude/lhlpohlBei BremenGermanyPhone: (49) 421 693 500Fax: (49) 421 693 5035

JLG Industries (Italia)Via Po. 2220010 Pregnana Milanese - MIItalyPhone: (39) 02 9359 5210Fax: (39) 02 9359 5845

JLG Latino Americana Ltda.Rua Eng. Carlos Stevenson,80-Suite 7113092-310 Campinas-SPBrazilPhone: (55) 19 3295 0407Fax: (55) 19 3295 1025

JLG Europe B.V.Jupiterstraat 2342132 HJ FoofddorpThe NetherlandsPhone: (31) 23 565 5665Fax: (31) 23 557 2493

JLG Industries (Norge AS)Sofeimyrveien 12N-1412 SofienyrNorwayPhone: (47) 6682 2000Fax: (47) 6682 2001

JLG PolskaUI. Krolewska00-060 WarsawaPolandPhone: (48) 91 4320 245Fax: (48) 91 4358 200

JLG Industries (Europe)Kilmartin Place, Tannochside ParkUddingston G71 5PHScotlandPhone: (44) 1 698 811005Fax: (44) 1 698 811055

JLG Industries (Pty) Ltd.Unit 1, 24 Industrial ComplexHerman StreetMeadowdaleGermistonSouth AfricaPhone: (27) 11 453 1334Fax: (27) 11 453 1342

Plataformas Elevadoras JLG Iberica, S.L.Trapadella, 2P.I. Castellbisbal Sur08755CastellbisbalSpainPhone: (34) 93 77 24700Fax: (34) 93 77 11762

JLG Industries (Sweden)Enkopingsvagen 150Box 704SE - 175 27 JarfallaSwedenPhone: (46) 8 506 59500Fax: (46) 8 506 59534

Documents

Service & Maintenance Manual - JLG Industriescsapps.jlg.com/OnlineManuals/Manuals/JLG/JLG Scissor Lifts/330_400CRT... · maintenance are inserted at the appropriate point in the manual