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INTRODUCTION

How to Use.This Manual

is manual is divided into 14 sections. The first page of each sec-n is marked with a black tab that lines up with one of the thumb

index tabs on this page and the back cover. You can quickly find thefirst ,page of each section without looking through a full table ofcontents. The symbols printed at the top corner of each page canalso be used as a quick reference system.

Each section includes:1. A table of contents, or an exploded view index showing:

0 Parts disassembly sequence.0 Bolt torques and thread sizes.l Page references to descriptions in text.

2. Disassembly/assembly procedures and tools.3. Inspection.4. Testing/troubleshooting.5. Repair.6. Adjustments.

. Special Information

m.Indicates astrong possibility of severe personal injuryor loss of4ife if instructions are not followed.

CAUTION: Indicates a possibility of personal injury or equipmentdamage if instructions are not followed.

NOTE: Gives helpful information.

ION: Detailed descriptions of standard workshop pro-cedures, safety principles and service operations are not included.,,.Please note that this manual does contain warnings and cautions ,against some specific service methods which could cause PER-.SONAL INJURY,. or could damage a vehicle or make it unsafe.Please understand that these warnings cannot cover all conceivableways in which service, whether or not recommended by HONDA,might be done, or of the possible hazardous consequences of eachconceivable way, nor -could HONDA investigate all such ways.Anyone using service procedures or tools, whether or not recom-mended by HONDA, must satisfy himself thorough/y that neitherpersonal safety nor vehicle safety will be jeopardized.

All information contained in this manual is based on the latest pro-duct information available at the time of printing. We reserve theright to make changes at any time without notice. No part of thispublication may be reproduced, stored in retrieval system, ortransmitted, in any form by any means, electronic, mechanical,photocopying, recording, or otherwise, without the prior writtenpermission of the publisher. This includes text, figures and tables.

Specifications

Maintenance

First Edition 7/90 1450 pagesAll Rights Reserved

HONDA MOTOR CO., LTD. * H e a t e r a n dService Publication Office Air Conditioner

Specifications Apply to U.S.A. and Canada

Chassis and Paint Lodes

U.S. Model

- Vehicle Identification Number ,- Transmission Number

JH4NAl

Serial Number.

MT00000 1

Manufacturer Codeand Vehicle Type

JH4: HONDA MOTOR CO.,LTD., JAPAN.

NAI : ACURA NSXTransmission Type

15: 5-speed Manual26: 4-speed Automatic

Check DigitModel Year

M: 1991Factory Code

T: Tochigi Factory JapanSerial Number

- Vehicle Identification Numberand Federal Motor VehicleSafety Standard Certification

- Engine Number

\\

r Paint CodeCOLORNH-547

. . .

. . .

. . .

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

The NSX includes a drivers side airbag, located in the steering wheel hub, as part of a Supplemental RestraintSystem (SRS).lnformation necessary to safely service the SRS is included in this Service Manual. Items marked *in each section include, or are located near, SRS components. Servicing, disassembling or replacing these itemswill require special cautions and tools, and should therefore be done by an authorized Acura dealer.

l To avoid rendering the SRS inoperative, which can lead to personal injury or death in the event of a severe fron-tal collision, all maintenance must be performed by an authorized Acura dealer.

l Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal injury caus-ed by unintentional activation of the airbag.

l All SRS electrical wiring harnesses are covered with yellow outer insulation and related components are locatedin the steering column, center console, dash, and dashboard lower panel. Do not use electrical test equipmenton these circuits. . .

Label Locations

SRS CAUTION LABELS: Refer to page 1-14.

I BATTERY CAUTION IALB CAUTION

I COOLING FANCAUTION

RADIATOR BLEEDPLUG CAUTION

AIR CONDITIONER

/ ;:. \.

wheels on the ground

MIS 15OP/S 2oo+?M/S 0.69-I .67 (7-17, 0.51-I .23)M/S 0.15-0.25 (1.5-2.5, 0.11-o. 18) (without rack)P/S 2.94 (30, 2.17)

M/S: Manual Steering P/S: Power Steering

- Suspension - Section 18rWhee lal ignment

Whee l

Wheel bearing

MEASUREMENT STANDARD (NEW)

Camber o Front at inspectionat adjustment

Rear at inspectionat adjustment

Caster o Front at inspectionat adjustment

Total toe FrontRear

Front wheel turning angle Inward wheelOutward wheel

Side sl ip FrontRear

Rim runout

End Play

AxialRadial

FrontRear

-00 20 530-00 20 210-I0 30 ?30-10 30 &IO+8O 00 245+8 00 215out 3.5 21In 6.0 +I33O 06 +2O26O 34Out 6.0 + 1In 9.0 -+I

O-O.7 (O-0.028)O-O.7 (O-0.028)

00

SERVICE LIMIT

-----

-

--0.05 (0.002)0.05 (0.002)

r Brakes - Section 19

Parking brake

MEASUREMENT

Play in stroke 200 N (20 kg, 44 lb)lever

Foot brake Pedal height (with floor mat removed) M/Tpedal A/T

Master cvlinder Piston-to-oushrod clearance

M/T: Manual Transmission A/T: Automatic Transmission

S T A N D A R D (NEWI 1 SERVICE LIMIT

To be locked whenpulled 1 O-l 4 notches218 (8.58)218 (8.58)

l-0.4 (O-0.01 6)

28.0 (1.10)21 .O (0.83)--

Il.0 (0.43)9.5 (0.37)

-

--

-

26.0 (1.02)19.0 (0.75)0.10 (0.004)0.10 (0.004)0.015 (0.0006)1.6 (0.06)1.6 (0.06)

3-12

r Air Conditioner - Section 22Unit of length: mm (in)

I I MEASUREMENT I STANDARD (NEW) IAir condit ioner Lubricant capaci ty Condenser 10 (0.34, 0.28)system cc (US 02, Imp 02) Evaporator 10 (0.34, 0.28)

Line or hose 10 (0.34, 0.28)Reservoir 20 (0.88, 0.56)

Compressor Lubricant capacity cc (US oz, Imp oz) 60-100 (2.03-3.38, 1.96-2.82)Stator coil resistance at 20C (68OF) 9 3.4-3.8Pulley-to-pressure plate clearance 0.35-0.65 (0.014-0.026)

Comoressor Deflection with 98 N (10 kg, 22 lb) 1 O-l 2 (0.39-0.47) with used beltbelt between the pulleys - 1 5.5-7.5 (0.22-0.30) with new belt

- Electrical - Section 23 I

I MEASUREMENTIgnition coil

Sprak Plug

Ignition timing

Battery

Rated voltage VPrimary winding resistance 61

TypeGapAt idling o B T D C

Lighting capacity (5-hour ratio) V-AH MITA K

Starting capacity (5-second ratio) V M/Tat - 15OC 15OFI. 300 A draw A/T

Alternator belt Deflection with 98 N (IO kg, 22 lb-ft)between oul levs

Alternator

MEASUREMENT

1 Output 13.5 V at hot A @6,000 rpmCoil resistance (rotor) 0Slip ring O.D.Brush lengthBrush spr ing tension g (02)

Starting motor 1 TvpelOutput kWM&a depthCommutator runoutCommutator O.D.Brush lengthBrush sor ina tension N Ika. lb)

STANDARD (NEW) SERVICE LIMIT

1 21.0+ 10%

See Section 231.0-l. 1 (0.039-0.043)

15O+2O (Red) BTDC

12-5212-559.2 min.9.4 min.18.8 min.

12-14 (0.47-0.55) with used belt7-9 (0.28-0.35) with new belt

STANDARD (NEW) SERVICE LIMIT

110 1022.7-3.1 -14.2-14.4 12.810.5 3.5300-360 (10.6-l 2.7) -

Reduction/l .60.5-0.8 (0.020-0.031) 0.2 (0.008)o-0.02 (0-0.001) 0.05 (0.002)29.9-30.0 (1.177-1.181) 29.0 (1.142)15.0-I 5.5 (0.590-0.610) 10.0 (0.394)18.1-23.9 (1.85-2.44, 4.1-5.4) -

M/T: Manual Transmission A/T: Automatic Transmission

3-13

Design Specification

Dimentions

Weight (USA)

Weight (CANADA)

ENGINE

STARTER

CLUTCH

TRANSMISSION

ITEM

Overal l LengthOverall WidthOveral l HeightWheelbaseTrack F/RGround ClearanceSeating Capacity

Gross Vehicle Weight Rating (GVWR)

Gross Vehicle Weight Rating (GVWR)

Type

Cylinder ArrangementBore and StrokeDisplacementCompression Rat ioValve TrainLubrication SystemFuel Required

Type/MakesNormal OutputNominal VoltageHour RatingDirection of Rotation

Weight

Clutch M/TA/T

Clutch Lining Area M/T

Transmission M/TA/T

Primary Reduction

TypeGear Ratio 1st

2nd3rd4th5thReverse

Final Reduct ion Gear typeGear rat io

METRIC ENGLISH

4,425 mm 174.0 in1,810 mm 71.3 in1,175 mm 48.3 in2,530 mm 99.6 in

1,510/1,530 mm 59.4160.2 in135 mm 5.3 in

2

1,610 kg 3,550 lb

1,610 kg 3,550 lb

Water cooled, 4-stroke DOHC with VTECgasol ine engine

90 VG-cylinder, transverse90.0 x 78.0 mm 3.54 x 3.07 in2,977 cm3 (cc) 181.6 cu in

10.2Belt driven, double (41 overhead camshafts

Forced and wet sumpPremium UNLEADED grade gasoline

with 91 Pump Octane Number(96 R.O.N.) or higher

Gear reduction/NIPPON DENS01.6 kW

1 2 v30 seconds

Counterclockwise as viewedfrom gear end

4.6 kg IO lb

Double plates dry, diaphragm springTorque converter

587.6 cm2 22.7 sq in

Synchronized 5-speed forward 1 reverseElectronically controlled

4-speed automatic; 1 reverseDirect 1 : 1

Manual Automatic

3.071 2.6111.727 1.5511.230 1.0250.967 0.6840.771 -3.186 1.909

Single helical gear4.062 4.428

NOTES

AIR CONDITIONER

STEERINGSYSTEM

SUSPENSION

ITEM METRIC I ENGLISH I NOTES

Cooling Capacity- Conditions:

Compressor RPMOutside Air TemperatureOutside Air HumidityCondenser Air TemperatureCondenser Air VelocityBlower Capacity

Compressor Type/MakesNo. of CylinderCapacityMax. SpeedLubricant Capacity

Condenser Tvw

Evaporator TvwAir Temperature

Blower TvpeMotor InputSpeed ControlMax. Capacity

Temp. control

Comp. clutch TvpePower Consumption

Refr igerant MeQuantity

Tvpe MITA/T

Overal l Rat io M/TA/T

Turns, Lock-to-LockSteering Wheel Dia.

Type, Front

Type, Rear

4,000 Kcal/h 15,872 BTU/h

1,800 rpm27 =C I 81 OF

50 %3 5 oc 95 OF

4.5 m/set 14.8 ft/sec420 m3/h 15,540 cu f t lh

Swash-plate type/NIPPON DENS01 0

155.3 cc/rev 1 94.7 cu in/rev7,600 rpm

80 cc 2.7 US oz

Corruaated fin tvpe

Corrugated fin type19.5 oc 67 OF

at 12V

Sirocco fan178W112V

Infinity variable460 m3/h 1 16,247 cu ftlh

Air-mix type

Dry, single plate, V-belt drive40 WI12 V

R 129505.8 g 77,9+d lb

Rack and pinionElectric, power assisted, rack and pinion

20.8 (18.2-20.8) (Manual variable)18.6 (Power steering)

3.24368 mm I 14.5 in

at 13.5 V

Shock Absorber, Front and Rear

M/T: Manual Transmission A/T: Automatic Transmission

Independent double wishbone with com-pliance pivot, coil spring with stabilizer

Independent double wishbone,coil spring with stabi l izer

Telescooic. hvdraulic nitroaen aas-filled

(contd)

3-15

Design Specification- Kontd)

WHEELALIGNMENT

BRAKE SYSTEM

TIRE

ELECTRICAL

ITEM METRIC ENGLISH NOTES

Camber Front -00 20Rear -I0 30

Caster 8T o e Front Out 3.5 mm Out 0.14 in

Rear In 8.0 mm In 0.24 in

Type, Front and Rear Power assisted self-adjustingventilated disc

Pad and Lining Surface Area: Front/Rear 58.0138.8 cm2 1 8.99/6.01 s q i nParking Brake Kind and Type Mechanical expanding, rear two wheel

brakes

Size Front: 205150 ZR 15 Rear: 225150 ZR 16165/80 D 15 (Folding spare tire)

Battery MIT: 12 V-52AH15HRA/T: 12 V-55AH15HR

Starter 12 V-l.6 kWAlternator 12 V-110 AFuses In The Fuse Box 7.5 A, 10 A, 15 A

In The Relay Box 7.5 A, 10 A, 15 A, 20 A, 30 A, 40 A, 50 AIn The Main Fuse Box 7.5A, IOA, 15A,20A,30A,40A, 120A

Headlights, High, Low 12V-65W, 5 5 WFront Turn Signal Lights 12 V-32 CP (SAE 1156)Front Position Light 12 v-5 w (SAE 3652)Rear Turn Signal Lights 12 v-45 CP (SAE 3497)Stop/Tail Lights 12 V-3212 CP (SAE 2057)Tail Lights 12 v-2 CP (SAE 194)Side Marker Lights Front 12 v-3 CP (SAE 168)

R e a r 12 v-3 CPBack-up Lights 12 V-32 W (SAE 1156)License Plate Lights 12 V-8 WGauge Lights 12 v-3.0 w, 1.4 wlndicater Lights 12 v-1.4wGlove Box and Fuse Lights 12 v-3.4 wDome Lights 12 v-5 wTrunk Lights 12 v-3.4 wDoor Courtesy Lights 12 v-3.4 wFootlight 12 v-3.4 wIllumination and Pilot Lights 12 V-l.4 W, 0.84 W

12 V-O.91 W, LEDDay Time Running Lights 12 V-32 CP Canada model only

Body Specifications mI 1,175 (46.3)

Unit: mm (in)

Maintenance

Lubrication Points ........................... 4 -2Maintenance Schedule ..................... 4 -4

Lubrication Points

For the details of lubrication points and types of lubricants to be applied, refer to the Illustrated Index and various workprocedures (such as Assembly/Reassembly, Replacement, Overhaul, Installation, etc.) contained in each section.

u o . LUBRICATION POINTS LUBRICANT

1 Engine API Service Grade: SGSAE viscosity: 10 W-30 recommendedFuel Efficient Oil:Identified by the words, Energy Conserving IISAE Viscosity: See chart below.

2 Transmission Manual API Service Grade: SF or SGSAE Viscosity: See chart below.

Automatic Honda Premium Formula Automatic TransmissionFluid or an equivalent DEXRON@ II type automatictransmission fluid

3 Brake Line (including anti-lock brake system)

4 Clutch Line ,

5 Shift lever pivots (Manual)6 Release fork (Manual)

7 Steering gearbox (Manual)8 Steering boots9 Steering column bushings

1 0 Steering ball joints1 1 Select lever (Automatic)1 2 Pedal linkage1 3 Intermediate shaft1 4 Brake master cylinder pushrod1 5 Trunk hinges1 6 Door hinges upper and lower1 7 Door opening detents1 8 Fuel filler lid1 9 Front hood hinges and latch20 Clutch master cylinder pushrod2 1 Tilt lever2 2 Parking brake cable end2 3 Throttle cable end2 4 Shift cable end and select cable end25 Rear hatch latch

2 6 Caliper Piston seal, Dust seal,Caliper pin, Piston

Recommended Engine OilAPI Service Grade: SGFuel Efficient Oil:Identified by the words, Energy Conserving II

Brake fluid DOT3 or DOT4

Brake fluid DOT3 or DOT4

Silicone grease with molybdenum disulfide

Multi-purpose grease

Silicone grease

Recommended Manual Transmission OilAPI Service Grade: SF or SG

) 13

I

0

4-3

MAINTENANCE ITEM MAINTENANCE INTERVALSe R = Replace C = Clean I = Inspect After inspection, clean, adjust, repair or replace if necessarv.

Service at the interval listedx 1,000 miles (or km) or x 1,000 miles 7.5 1 5 22.5 3 0 37.5 4 5 52.5 6 0 67.5 7 5 82.5 9 0

after that number of months, x 1,000 km 1 2 24 3 6 4 8 6 0 7 2 8 4 9 6 1 0 8 1 2 0 1 3 2 1 4 4whichever comes first.

m o n t h s 6 1 2 1 8 2 4 3 0 3 6 4 2 4 8 5 4 6 0 6 6 7 2

Emission Related

0 Air cleaner element

Idle speed

3 Engine oi l

9 Engine oil filter

Alternator drive belt

Cooling system hoses and connections2Manual transmission oi l

Automatic transmission fluid

R

R

l Check oil and coolant level at each fuel stop.q Under severe driving conditions, service these items more often.

NOTESSEC

&P A G E

jJ

I

@I 11-11:Manual: 800 2 50 rpmAutomatic: 750 f 50 rpm 11-84

(in gear)

Check with CO meter 1 1 l-12!

1 l-12f

1 1 l-13!15 * 2 (Red) BTDC 123-91

If c l icking sound is heard as you pinch thePCV hose between the PCV valve and in- 11-134take manifold, valve is OK.

Intake: 0.15-0.19 mmfO.O06-0.007 in)

Exhaust: 0.17-0.21 mm(0.007-0.008 in)

The rubber fuel hoses need periodicreplacement since they are subject tocracks and deter iorat ion during a longper iod of use.

Check fuel l ines for loose connections,cracks and deteriorat ion.Ret ighten loose connect ions and replaceany damaged or deformed parts.

NGK: PFRGG-11

~

Automatic: 12.0 C (12.7 US at, 1016 Imo at)Check specific gravity for freezing point

2.7 P (2.9 US qt. 2.4 Imp qt) 13-3

2.9 P (3.1 US qt, 2.6 Imp qt) 14-94

I For cars sold in Carifornia, this service is recommended only; other areas, it is required.2 Tension adjustment only.3 Thereafter, replace every 2 years or 30,000 miles (48,000 km), whichever comes first.

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Construction and Function

Outline .......................................... 5-2

Variable Valve Timing and Lift

Electronic Control System (VTEC) ... 5 -4

Cylinder Head ................................ 5-9

Lubrication System ......................... 5-11

Exhaust System ............................. 5-13

Cooling ......................................... 5-14

. . .

Outline- Description

This engine is a 2,977 cc DOHC mid-ship unit having 6 cylinders of 90 -V configuration; it is water cooled and equip-ped with a center plug type pent roof combustion chamber. It is specified for unleaded fuel and uses a PGM-FI (Multi-point injection) system. This engine incorporates a new mechanism called Honda Variable Valve Timing and Lift Elec-tronic Control System (VTEC). This mechanism, the worlds first, allows the timing and lift of the intake and exhaustvalves to be changed simultaneously. The engine also includes a new electronically controlled intake manifold systemthat can change the volume of the intake chamber.

e This engine has the following new features.l VTEC; High output and a broad power band is achieved through control of low-speed and high-speed valve operation

by the PGM-FI ECU.(Two knock sensors are used to detect octane level of the fuel.)

0 Titanium connecting rods; Accommodate high rotation speed and high output. Titanium material of light weight andhigh strength is used for the connecting rods.(Strength is at the same level as iron.)(Weight is about 30% lighter than iron.)

0 New mechanism to the intake system; Increased low and middle speed torque and higher output can both be achievedby switching the chamber volume of the intake manifold according to engine speed. This is electronically controlled.

l Cooling system for the mid-ship engine:- Radiator located in front compartment (An aluminum alloy radiator and pipes made of aluminum alloy)- Engine room cooling fan- Expansion tank

l The cylinder block is highly rigid with deep water jackets.

l In order to achieve lighter weight. magnesium.is used for the following parts:l Cylinder head coverl Intake manifold coverl Intake manifold chamber

Major Specifications

Type Water-cooled V6-90 Cross Flow

Displacement 2,977 cm3 (181.6 cu.in)

Bore x Stroke 90 x 78 mm (3.54 x 3.07 in)

Compression Ratio 10.2

Cam, Valve Mechanism DOHC (Ccamshafts), VTEC

Valve Train

Fuel Supply System

Belt Driven

PGM-FI {Multi-Point Injection)

. 5-3

Variable Valve Timing and Lltt tlectronlcControl System (VTEC)

Outline

The engine is equipped with multiple cam lobes per cylinder, providing one valve timing and lift profile at low speed and adifferent profile at high speed. Switch-over from one profile to the other is controlled electronially, and is selected bymonitoring current engine speed and load.

@ CAM LOBES FOR LOW RPM@ CAM LOBES FOR HIGH RPM@ PRIMARY ROCKER ARM@ MID ROCKER ARM@ SECONDARY ROCKER ARM@ LOST MOTION ASSEMBLY@ INTAKE VALVE@ EXHAUST VALVE

5-4

191. . . ..- I

In general, it would be ideal if the high rpm performance of a racing engine and the low rpm performance of a standardpassenger car engine could be combined in a single engine. This would result in a maximum performance engine with awide power band. Two of the major differences between racing engines and standard engines are the timing of the in-take/exhaust valves and the degree of valve lift. Racing engines have longer intake/exhaust timing and a higher valve liftthan standard engines. The Honda Variable Valve Timing and Lift Electronic Control System takes this into account.When valve actuation is adjusted for low rpm timing and lift, low rpm torque is better than in a standard engine. Whenvalve actuation is then adjusted for high rpm timing and lift, output improves to the level that a racing engine can offer.Until now, few variable valve timing systems have been commercialized. In those that have, only the time that bothvalves are open (intake/exhaust overlap) could be changed. Hondas system is the first in the world in which both thevalve timing and the degree of valve lift can be changed as needed, making it the most advanced valve train mechanismavailable. -

Comparison of Valve Lift of Racing Engines vs. Mass Produced Engines

Racing EngineVariable Timing

& Lift Engine Standard Engine

Valve Timing(exhaust/intake)

il&e I= lm

Valve Lift Exhaust Intake Exhaust Intake Exhaust Intake

Max. Power 0 0

Low rpm Torque 0 0

idling Stability 0 0

*TDC = Top Dead Center *BDC = Bottom Dead Center0 = Optimum Characteristic

The engine is equipped with tzo valve timing and lift settings which change according to driving conditions.

Low rpm + 1 + High rpm

Variable valve timingand Lift engine

RPM switch overpoint

5-5

Variable Valve Timing and Lift ElectronicControl System (VTEC)

Mechanism

At Low rpm:As shown, the primary and secondary rocker arms located on both sides are not connected to the mid rocker arm but aredriven separately by cam lobes A and B at different timing and lift. Although the mid rocker arm is following the centercam lobe with the lost-motion assembly, it has no effect on the opening and closing of the valves in the low rpm range.

At Low rpm:CAM PROFILES FOR

A and 6 cam lobes

RETURN SPRING

HYDRAUPISTION STOPPER PISTON

drive the rocker armsseparately.

PISTON (B) / I \PRIMARY MID

SECONDARY

ROCKER ARM ROCKER ARMROCKER ARM

At High rpm:When driving at high rpm, the built-in piston moves in the direction shown by the arrow in the figure below. As a result,the primary, secondary, and mid rocker arms are linked by 2 hydraulic pistons (like a skewer) and the 3 rocker arms moveas a single unit. In this state, all the rocker arms are driven by cam lobe C opening and closing the valves at the valve tim-ing and lift set for high operation.

At High rpm:

CAM PROFILES FORI HIGH RPM

HYDRAUlX HYdRAULlCPISTION (Al PISTON (B)

STOPPERPISTON

The rocker arms are linkedvia the hydraulic piston.Cam lobe C drives the rockerarms.

*

5-6

0a

- Control System

The control system for this mechanism, as shown below, constantly monitors the changes in engine status such as load,rpm and vehicle speed. This information is transmitted to the Control Unit.

Valve Timing Change ConditionsEngine RPM: 5,800-6,000 rpmVehicle Speed: 5 km/h (3 MPH) or fasterWater Temperature: 60C (140F) or higher

Control System

, w

t2 SOLENOID VALVE (SPOOL VALVE)3IL

$

fromOIL PUMP - I

+--I W a t e r temp I

(contd)

5-7

Variable Valve Timing and Lift ElectronicControl System (VTEC)- Control System

Lost Motion MechanismThe mid rocker arm is always driven by the high-speed cam lobe, even at low speeds. At low speeds, the lost motionmechanism keeps the mid rocker arm in contact with the high-speed cam lobe. At high speeds, the lost motionmechanism acts as part of the valve spring load.

CAM PROFILE

GUIDE HOLDERGUIDE HOLDER

II

LOST MOTlCiN ASSEMBLY

Hydraulic Pressure Control MechanismSpool valve/hydraulic pressure switchThe solenoid valve, in response to a signal from the PGM-FI ECU, closes the oil passage to the rocker arm at low speed.This cuts oil pressure to the hydraulic pistons in the rocker arms so the arms operate independently. At high speed, theECU opens the solenoid valve. The increased oil pressure causes the hydraulic pistons to lock the primary, secondary,and mid rocker arms together.The oil pressure switch serves as a sensor to determine if the switch-over has taken place in response to the ECU signal.

OIL PRESSURE

SPOOL VALVE(contd)

5-8

-a

Cylinder Head Ell . e.-I- Camshaft

The camshaft is a cast piece. By improving dimensional accuracy, it became possible to achieve minimum space be-tween cams, thus allowing a more compact cylinder head. Each camshaft is supported on four bearing journals with forc-ed lubrication. On the right end of each camshaft is a driven pulley. The exhaust and intake cycles require a total of 36cam lobes to open and close the va)ves.

No. 6 No. 5 No. 4 c- FRONT BANKNo. 3 No. 2 No. 1 f-REAR BANK

n r-7 ilINTAKE

CAMSHAFTJOURNALS

EXHAUST

No. 6 No. 5 No. 4 - FRONT BANKNo. 3 No. 2 No. 1 - R E A R B A N K

Manual Transmission

A: PRIMARYB: MIDC: SECONDARY

@ : Intake valve open+ : Exhaust valve open

Automatic Transmission

Low-speed valve timing High-speed valve timing

5-9

The valves are opened and closed by rocker arms driven by the camshaft. The rocker arm lever ratio is set to the optimumvalue, keeping cam lift to the minimum while increasing valve lift, thus improving intake/exhaust efficiency.

Valve mecificationsUnit: mm (in)

INTAKE EXHAUST

HEAD DIAMETER

SHAFT DIAMETER

OVERALL LENGTH

VALVE LIFTMIT

A/T

35 (1.38)

5.5 (0.22)

112.45 (4.43)

A: 8.7B: 10.2"C: 8.3

A: 9.0B: 9.5c: 8.6

30 (1.18)

5.5 (0.22)

111.55 (4.39)

A: 7.78: 9.0*c: 7.4

A: 7.7B: 9.0c: 7.4

* Indicates high-speed valves

IShaft diameter

5-10

Lubrication System El. . . .-ILubrication Flow

CRANKSHAFT -MAIN JOURNAL

MAIN BEARINGCAP BRIDGE

tI

Front

No. 6 No. 5 No. 4

No. 3 No. 2 N o . 1

t t t1

Rear

SPOOL VALVE

- ROCKER SHAFT

/

ORIFICES

/ CYLINDER HEAD

LIEF VALVE

OIL FILTER

IENGINE OILCOOLER

CYLINDER HEADORIF ICE

ROCKER SHAFTORIFICES

5-11

- Oil Passage

The lubrication system is a full filtration circulation type. The oil pump is directly linked to the crankshaft; oil to the oilpump is pulled through the oil strainer, after which pressure is regulated by the pump relief valve. It is then filteredthrough the oil filter and pumped to the cylinder block and cylinder head. A baffle plate is provided inside the oil pan; thebaffle plate helps minimize the changes in oil level produced inside the pan while driving will affect the amount of oil go-ing to the pump.

CAM HOLDERPIPE

ROCKER SHAFT

/OIL FILTER

OIL SiRAlNER

SHAFT

5-12

aExhaust System m. . . .-I

- Dual Exhaust System

Features0 A compact dual exhaust system is used to provide low back pressure.

0 Sound tuning has been optimized to give a sporty exhaust sound note suitable to this type of car. This is done by a col-lection chamber in Exhaust Pipe B.

SILENCER

\

MANIFOLD

CONVERTER

FRONi EXHAUSTMANIFOLD

Exhaust gasfromfront bank

COLLECTION CHAMBER

/Exhaust gasfromrear bank

5-13

- Cooling System

Two cooling systems are employed:An antifreeze/water system with the radiator mounted in the front of the vehicle.An air-cooling system driven by fan mounted in the engine compartment.

BLEEDER

EXPANSION.TANK

-I DRhN

RADIATOR

WATER VALVE

HEATER CORE

elYllYC ILCOOLER

BLEEDER

THERMOSENS

THERMOSTAT

THROGLEBODY

-BREATHER PIPE

m. . . .-Ie

a

- Radiator

The radiator, made of aluminum alloy, is mounted in the front of the vehicle to gain maximum cooling efficiency from airpassage. It is a corrugated-fin type, double row alminum core radiator with electric cooling fan. Since the tubes are in aline, the volume of the cooling water in the radiator is reduced for less weight. The upper and lower tanks are made ofresinous material for reduced weight and increased corrosion protection.

The engine compartment cooling fan is mounted on the right side. It operates in conjunction with the radiators electriccooling fan in high mode.

The expansion tank is used to separate air out of the coolant circulating through the system.

Radiator Specifications

Radiator volume (kcal/h) 46,000

Height (mm) 340

Core size Width (mm) 688.1

Thickness (mm) 3 2

Fin pitch (mm) 2.5

RESINOUS UPPER TANK

OVERFLOW TUBE

i CORE WIDTH -

RESINOUS LOWER TANK

TANK CAP (PRESSURE TYPE)

EXPANSIONTANK

5-15

Engine Removal/Installation

I5-18

Ref. No. Tool Number

0 07MAC-SLOOIOO0 07941-6920003

Description Qty Page Reference

Ball Joint Remover 1 5 - 2 4Ball Joint Remover 1 5 - 2 4

Engine Removal/Installation

l Make sure jacks and safety stands are placed properly and hoist brackets are attached to the correctpositions on the engine (See Section 1).

0 Make sure the car will not roll off stands and failwhile you are working under it.

CAUTION:l Use front and rear fender covers to avoid damaging

painted surfaces.l Unspecified items are common for the M/T cars, A/T

cars, and the AIC equipped cars.l Unplug the wiring connectors carefully while holding

the coupler and the connector portion to avoiddamage.

l Mark all wiring and hoses to avoid mis-connection.Also, be sure that they do not contact other wiring orhoses or interference with other parts.

l If the ground clearance should be retained, use ascissors jack and install the rubber spacers to the coilsprings (page l-6).

0 Put rubber pads under the jacking points when usingjacks or safety stands to avoid damaging body (pagel-7, I-81.

1 . Move the seat bottoms and backs as far forward asthey will go.

2. Disconnect the battery negative terminal first, thenthe positive terminal.

3. Remove the expansion tank cap to speed draining.

m Use care when removing the expan-sion tank cap to avoid scalding by hot coolant orsteam.

4. Raise the hoist to full height.

5. Drain the coolant (See Section 10).l Loosen the drain plug from the radiator lower

tank.l Remove two drain bolts from the water pipes

Reinstall the drain bolts with new washers.l Loosen the front and rear engine drain bolts to

drain coolant from cylinder heads. Connect rub-ber hoses to the drain bolts for easy operation.

6. Drain transmission oil/fluid. Use a 3/8 drivesocket wrench to remove the drain plug. Reinstallthe drain plug using a new washer.

7. Drain the engine oil. Reinstall the drain plug using anew washer.

8. Lower the hoist.

9. Remove the rear hatch (See Section 20).

10. Remove the engine cover (See Section 20).

11. Remove the rear hatch scoop (See Section 20).

I 12. Remove the strut bar.

STRUT BAR

/

*IO x 1.25 mm39 N-m (3.9 kg-m,/

CAP

28 lb-W

* : CORROSION RESISTANT BOLT/

(contd)

5-19

Engine Removal/Installation- (contd)

13. Disconnect the resistor connector and fan motorconnector, then remove the engine room fanassembly.

i26 x 1.0 mm10 N-m (1.0 kg.m, 7 lb-ft)

ENGINE R ROOMFAN NNECTOR

a6xl.Omm10 Nom (I .O kg-m, 7 lb-ft)

14. Remove the rear trim panels behind thepassengers seat, then disconnect four connectorsfrom ECU and five connectors from floor wireharness.

ENGINE WIREHARNESS CO

HARNESS

Ir : CORROSION RESISTANT BOLT

FUELFUEL PUMP RESISTERPUMP RESISTER

El. . . .-I

15. Remove the intake manifold plate and the topcover.

16. Remove the throttle cable by loosening the locknut,then slip the cable end out of the throttle bracketand accelerator linkage.

NOTE:0 Take care not to bend the cable when removing

it. Always replace a kinked cable with a newone.

0 Adjust the throttle cable when installing (SeeSection 1 I).

INTAKE MANIFOLDTOP

12 Nom (1.2 kg-m, 9 lb-ft)

THROTTLE CABLE

ADJUSTING NUT

-3 X / L@Cj

Engine Removal/Installationa (contd)

21. Remove the breather hose, then remove the air in-take duct and the air cleaner case.

~26 x 1.0 mm10 N-m (1 .O kg-m, 7 lb-ft) AIR CLEANER

BREATtiER PIPE

22. Disconnect the charcoal canister hose from throttlebody.

23. Disconnect the brake booster vaccium hose fromthe intake manifold.

CHARCOAL CANISTER

CHARCOAL CiNISTERHOSE I

BRAKE BOOSTERVACUUM HOSE

24. Disconnect the two engine wire harness connec-tors from the side wire harness at left side ofengine compartment, and remove the engine wireharness terminal and the starter cable terminalfrom the under hood relay box and clamps.

25. Remove the ground cable from the transmission.

FUSE BOX ,---

(1 .O kg-m,

ENGINE GIREHARNESS

7 lb-ftl -

26. Remove the water hoses and the heater hose fromthe water passage.

HEATER HOSE

WATER ilOSES

Q : CORROSION RESISTANT BOLT

27. Disconnect the three connectors, then remove theemission control box. Fix it to the intake manifold.0 Do not disconnect the vacuum hoses.

*6xl.Omm10 Nom (I .O kg-m,7 lb-ft)

EMISSION CONTROL

CONNiCTORS

28. Move the trunk carpet and disconnect the anti-lockbrake right sensor connector. Push the wire andconnector throuah the bodv hole into the engine

0 compartment.29. Remove the front engine mounting bolt (page

5-28).

ANTI-LOCK BRAKE SENSORWIRE CONNECTOR

30. Raise hoist to full height.

31. Remove the clutch slave cylinder from thetransmission case (M/T, See Section 12)0 Do not disconnect the clutch hose.

32. Remove the lower cover, then remove the shiftcable and select cable with cable bracket (M/T, SeeSection 13).

33. Remove the cover, then remove the shift cable(A/T See Section 14).

NOTE:l Take care not to bend the cable when removing

it. Always replace a kinked cable with a newone.

0 Adjust the cables when installing.

34. Remove the engine under guard and the center rodassembly.

A/T:

ROL LEVER

SHIFT

*8x 1.25min22 Nom (2.2 kg-m.16 lb-ft)

\I 6xi.Omm0.8 Nom (8 kg-m, 6 lb-ftl

6 x l.Omm12 N-m (I .2 kg-m, 9 lb-ft)

UNDER GUARD*10x 2 5 m m

60 N*m (6.0 kg-m, 43 lb-ft)

Q : CORROSION RESISTANT BOLT/NUT (contd)

5-23

Engine Removal/Installation- (contd)

35. Remove the rear beam rod assembly.

36. Remove the front beam. Remove the A/C com-pressor, then reinstall the front beam and retorquethe two nuts to the front beam.

NOTE:0 Do not remove the compressor hoses.0 Hang the A/C compressor with wire or rope as

shown. Do not let it hang from hoses.

37. Remove the left and right parking brake cables.

39. Remove the rear brake hoses. Plug the brake pipeswith rubber caps.

40. Remove the anti-lock brake sensor wire clamps.

41. Remove the ball joints from the suspension lowercontrol arms (use ball joint remover 07MAC-SLOOlOO), and the toe control arms (use ball jointremover 07941-6920003).

CAUTION: Make sure that the reference marks onthe control arm are aligned.

38. Remove the stabilizer links and separate thedamper and the suspension lower control arms.

Hang with

l Do not remove the compressor hoses.l Hang the AK compressor with wire or rope as shown.

Do not let it hang from hoses.

V* Retorque the two nuts

TOE CONTROL ARM

I10 x 1.25 mm

f-1 CASTLE NUT

DAMPER.60 N-m (6.0 kg-m,

\

/ SELF-LOCKING NUT BALL JOINT REMOVERSTABILIZER 95 N-m (9.5 kg-m, 69 lb-ft)

412 x 1.25 mmSELF-LOCKING NUT

10 N*m (1.0 kg-m, 7 lb-ft)

ReplaceANTI-LOCK BRAKE

86 Nom (8.5 kg-m, 62 lb-ft)SENSOR WIRE CLAMP

a : CORROSION RESISTANT BOLT/NUT

El. . . .-I

42. Remove the oxygen sensor connectors.

43. Remove the front exhaust pipe A and catalyticconverter.

44. Remove the self-locking nuts, then separate thecatalytic converter and exhaust silencer.

CAUTION:0 Do not use air wrench or hammer to remove ex-

haust pipes or catalytic converters if the oxygensensors are not to be removed.

0 Do not use air wrench for tightening self-lockingnuts on exhaust pipes or catalytic converters ifthe oxygen sensors are not to be removed.

NOTE: Use new gaskets and self-locking nutswhen reassembling.

SELF-LOCKING NUTSlOx1.25mm34 N-m (3.4 kg-m.25 lb-ft)

n

.YTIC

\ Replace.FRONT EX PIPE

SELF-LOCKING NUT10 x 1.25 mm55 N-m 15.5 kg-m,40 lb-ft)

45. Remove the half shaft heat cover

46. Remove the driveshafts.

NOTE:o Coat all precision finished surfaces with clean

engine oil or grease.0 Tie plastic bags over the driveshaft ends.

RINGace.

DRIVEiiHAFT

(contd)

5-25

Engine Removal/Installation- (contd)

47. Loosen the rear beam side bracket mounting bolts 50. Remove the side engine mount and bolts, thenone or two turns, then remove the mounting bolts push the side engine mounting bracket into theexcept the four bolts shown. support bracket of the body.

48. Lo.wer hoist, attach a chain hoist to the engine. 51 .Remove the transmission mounting bolt.

49. Install the front engine mounting bolt, torque thenut temporarily.

BODY SUPPORTBRACKET \

Do not removethese bolts untilstep 52.

TRANSMISSION MOUNTING

Do not .removethese bolts untilstep 52.

52. Remove the four mounting bolts from the rearbeam side bracket.

55. Slowly lower the engine assembly on to a truck.

53. Lower the engine, suspension and beam assemblya few inches with the chain hoist.

56. Remove the chain hoist from the engine.

57. Raise the body with the hoist. Roll the engineassembly from under the body.

54. Check that wires and hoses are completely remov-ed from the engine assembly.

TRUCK

GUIDE HOLE(BODY)

GUlDiHOLE \(SIDE BEAM) SCREWDRIVER

, NOTE: When installing, align the bolt holes of thebeam brackets and body with screwdriver.

(contd)

5-27P

Engine Removal/Installation(contd)

60. Attach a chain hoist to the engine. Remove thefront and rear mounting bolts, then separate theengine from the suspension and the beamassembly.

CAUTION: Do not hit the engine oil cooler on therear right beam bracket.

GINE

61. Install the engine in the reverse order of removal:

NOTE:0 Align the bolt holes of the beam brackets and

body with screwdriver (page 5-27).l Temporarily torque the two front beam nuts and

front engine mounting bolt when installing theA/C compressor.

0 Combine the front beam and the rear beam rodassembly, then torque the four mounting bolts.

0 Check that the set ring on the end of eachdriveshaft clicks into place.

CAUTION: Use new set ring on installation.

5 - 2 8

After the engine is in place:l Torque the engine mounting bolts in sequence

shown below.

CAUTION: Failure to tighten the bolts in the propersequence can cause excessive noise and vibrationand reduce bushing life; check that the bushingsare not twisted or offset.

l Bleed air from the cooling system (See Section IO)l Bleed air from the brake lines (See Section 19)0 Adjust the throttle cable tension.0 Check the clutch pedal free play.0 Adjust the clutch guide assemblies when

disassembling clutch (See Section 12).

*IO x 1.25 mm60 N-m 16.0 kg-m. 43 lb-ft)

0 Check that the tVsnsmission shifts into gearsmoothly (M/T See Section 13, A/T See Section14).

0 Adjust the alternator belt (See Section 23).0 Adjust the A/C belt (See Section 22).0 Clean battery posts and cable terminals with sand-

paper, assemble, then apply grease to preventcorrosion.

0 Inspect for fuel leakage:l After assembling fuel line parts, turn on the igni-

tion switch (do not operate the starter) so thatthe fuel pump is operated for approximately twoseconds and the fuel is pressurized. Repeat thisoperation two or three times and check whetherany fuel leakage has occurred at any point in thefuel line.

TRANSMISSIONMOUNT (A/T)

012 x 1.25 mm

95 Nom (9.5 kg-m.

69 lb - f t ) \ ,

SPECIAL BOLT*I2 x 1.25 mm

77 Nom (7.7 kg-m,56 lb-ft)Re lace.P *10x 1.25mm 473 Nom (7.3 kg-m, 53 lb-ft)

60 Nom 16.0 ka-m A **I2 X 1.25 m m--- . . . . . .

TRANSMISSIONMOUNT (A/T)

SPEC;AL NUT*43v, 3Cmm

RUBBER CAP

a12 x 1.25 mma-r II a_ r kg-m, 76 lb-ft)

w IL n I.& ..mm.m

77 N-m 17 7 kn-m A/T: *IO x 1.25 mm^^ -. ,^ ^ .-m, 43 lb-ft)

*: CORROSION RESISTANTtXJ N*fll (I).0 KQ

BOLT/NUT

,, .- . . . ,..- ..- . . . .56 lb-ft)Replace. (contd)

5-29

Engine Removal/Installation- (contd)

NOTE: For manifold replacement,

8x1.25mm30 N*m (3.0 ka-m.

Additional Torque Valve Specifications: 8 x 1.25 mm 10 x 1.25 mm

A/T TRANSMISSION HANGERS

refer to Section

n 8 x i.25 mm- I- 11 22N*m(2.2kg-m,

ALT&INATOR 1BRACKET ?DSTIFFENER

MIT TRANSMISSIONHANGER8

1

1 2 x 1.25mm75 Nom (7.5 kg-m, 54 lb-ft)

HALF SHAFTSUPPORTBASE

AX BRACKET

HALF SHAFTHEAT COVER

10 N-m (I .O kg-m, 7 lb-ft)

5-30

m Sub-frame Torque Value Specifications:

------- R. REAR BRACKET *IO x 1.25 mm

I

60 N*m (6.0 kg-m,43 lb-ft)

I

*lO x 1.25 mm60 N-m (6.0 kg-m43 lb-h)

.

--

L. REAR BRACKET

---

*IO x 1.25 mm60 N*m (6.0 kg-m, 43 lb+)

60 N-m (6.0 kg-m,

,*I0 x 1.25 mm60 N-m (6.0 kg-m, 43 lb-ft)

v 412 x I.26 mm95 N-m (9.5 kg-m, 6 9 lb-ft)* 10 x 1.25 mm60 N-m (6.0 kg-m, 43 lb-ft)

T?: CORROSION RESISTANT BOLT/NUT

Cylinder Head/Valve Train

Special Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2Illustrated Index . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

VTECElectrical Connections . . . . . . . . . . . . . . 6-8.Troubleshooting- Self-diagnostic Procedure . . . . . 6-10Troubleshooting Flowchart- Spool Valve . . . . . . . . . . . . . . . . . . . ...*. 6-15- Oil Pressure Switch . . . . . . . . . . . . . 6-17Spool Valve Inspection . . . . . . . . . . . . . 6-20

Timing BeltIllustrated Index . . . . . . . . . . . . . . . . . . . . . . 6-21Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-22Tension Adjustment . . . . . . . . . . . . ...*. 6-22Removal ..*.............................. 6-23Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25

CRANKlCYL Sensor . . . . . . . . . . . . . . . . . . . . 6-27

Cylinder Head Removal . . . . ..*......... 6-28

Rocker Arms and ShaftsLocation . . . . . . . . . . . . . . . . . . . . . . . ..*...... 6-35Inspection ............................... 6-36Clearance ............................... 6-37

Camshaft inspection ................... 6-38Valve and Valve Seals ................. 6-40Cylinder Heads ........................... 6-41Valve Seats ............................... 6-42Valve Guides .............................. 6-44Valve Spring and Valve Seals ....... 6-46Cylinder Head Installation ............ 6-47Rocker Arms .............................. 6-49Camshafts ................................. 6-49Rocker Arms Inspection ............... 6-52Valve Clearance Adjustment ........ 6-54

Special Tools

Ref. No. Tool Number Description

0 07HAH-PJ701 OA Valve Guide Reamer, 5.5 mm0 07LAJ-PT301 OA Test Harness0 07MAA-PR70110 Tappet AdjusterGO 07MAA-PR70120 Tappet Locknut Wrench0 07MAJ-PR70100 Test Harness@ 07MAJ-PR70200 VTEC Plug0 07757-PJIOIOA8

Valve Spring Compressor Attachment07742-0010100 Valve Guide Driver, 5.5 mm

my Page Reference

1 6-451 6 - 1 11 6-551 6-551 6-l 11 6-52, 5 31 6-401 6-44, 45

6-2

Cylinder Head/Valve TrainIllustrated Index

CAUTION: To avoid damaging the cylinder head, wait

until the coolant temperature drops below 38OC (TOOoF)

before removing it.NOTE:

0 Use new O-rings and gaskets when reassembling.l Replace rubber seals, if damaged or deteriorated.0 Prior to installing the cylinder head cover, apply a thin

layer of liquid gasket to the mating surface of thecylinder head, cover and rubber seals to prevent therubber seal from failing off.

0 After installation, fill the engine with oil up to thespecified level, run the engine for more than 3minutes, then check for oil leakage.

0 When installing the new crankshaft;@tighten hte crankshaft pulley bolt to 280 N.m (28kg-m, 203 lb-ft), @ loosen it bolt, @I retighten it to250 N-m (25 kg-m, 181 lb-ft).

WASHER AND

CYLINDER GROMMET

HEAD COVER I

CAP NUT

COVER

RUBER SEALSReplace when damagedor deteriorated

6x 1.0 mm12Nm (1.2 kg-m,9 lb-ftl

\

6x 1.0 m m

CYLINDER HEAD

RUBBER SEALSReplace when damagedor deteriorated.

TIMING BELTREAR MIDDLECOVER

TIMING BELTinspection, page 6-22Adjustment, page 6-22Replacement, page 6-23Replace every 90,000 miles(144,000 km) or 72 months.

TIMING BELTFRONT MIDDLECOVER

ADJUSTING BOLTlOx1.25mm43N.m (4.3 kg-m,31 lb-ft)For adjustment onl

Remove any oi l .

surface facing in.Remove any oil.

CRANKSHAFT PULLEYRemove any oi l .

SPECIAL BOLT

TIMING BELTDRIVE PULLEY

&W Remove any oil.16x 1.6 mm250N.m (25 kg-m,181 lb-ftTightening torque fora new crankshaft.

with concavesurface facing out.Remove any oi l .

280-r0+250N*m .

the bolt threads, but notto the surface thatcontacts the wahser.

A/C ADJUSTINGPULLEY BRACKET

9 lb-ft)

6x 1.0 mm12N.m (I .2 kg-m.

\AIC BELT

9 lb-ftt Adjustment, Section 22 (contdj

6-3

Cylinder HeadNaIve TrainIllustrated Index (contd)

NOTE:l Use new O-rings and gaskets when reassembling.l Replace rubber seals, if damaged or deteriorated.

6x 1.0 mmION-m (1.0 kg-m,7 lb-ft)

CAM HOLDER\

8x 1.25 mm22N.m (2.2 kg-m, 18 lb-ft)AD& oil to the bo It threads.

D O W E L P I N \ \ \ -m

10x 1.25 mm70N.m (7.0 kg-m,51 lb-ft) \

DWEi PIN

FRONT INTAKECAMSHAFT

ER SEALS

FRONT EXHAUST

6 x-1 .O mm

\

RLi88ER SEALS12N.m (1.2 kg-m, Replace when damaged9 lb-ft) or deteriorated

TIMING BELTCOVER PLATE

I% CAM PULLEY

REAR SPOOL VALVETroubleshooting, page 6-15

\

6x l.Omm12N*m (1.2 kg-m,9 lb-ft)

I

8 x 1.25mm22Nm (2.2 kg-m,16 lb-ft)

/ TW SENSOR

SCREENReplace.

180Nm (1.8 kg-m, 13 lb-ftlO-RING Replace.

8 x 1.25mm22N*m (2.2 kg-m, 16 lb-ft)

FRONT SPOOL VALVETroubleshooting, page 6-l 6

I.- . . . ,...- .-a . . . .

43 lb-ft)

OIL PRESSURE SENSOR

8 x 1.25mm22Nm (2.2 kg-m,1 6 l b - f t )

DOWEL PIN

P O-RINGReplace.

RADIATOR FANCONTROL SENSOR,

1 -\

\

28N*m (2.6 kg-m,20 lb-ftt

O-RINGReplace.

IROCKER SHAFTORIF ICE

RCiCKER ARM ASSEMBLY(PRIMARY, MID, SECONDARY)Inspection, page 6-36

Remove with 5 mmbolt and clean.

kontdl

6-5I

Cylinder Head/Valve TrainIllustrated Index (contd)

CAUTION:0 To avoid damaging the cylinder head, wait until the coolant temperature drops below 38C (I OOF) before removing it.0 In handling a metal gasket, care should be taken not to fold it or damage the contact surface of the gasket.

NOTE: Use new O-rings and gaskets when reassembling.

Prior to reassembling, clean all the parts in solvent, dry them, and apply lubricant to any contact parts.

INTAKE VALVEVALVE KEEPERSSPRING OUTER _

CYLINDER HEAD BOLTS11 x 1.5mm78N.m (7.8 kg-m, 56 lb-ftApply engine oil tothe bolt threads.

\

VALVE GUIDE

LOST MOTION

VALVE SPRING

CYLINDER HEAD BOLTS11 x 1.5m78N.m (7.8 kg-m, 56 Ib-Apply engine oil tothe bolt threads.

ALVE SPRING SEAT

EXHAUST VALVE

EXHAUST VALVE SPRING RETAINER

VALVE KEEPERS

VALVE SEAL

LOST MOTIONA!XFMRI V

GASKET (METAL)Replace.

CYLINDER HEADGASKET WETAL)Replace.

EL P INS

LINDER HEAD ORIFICERemove with 8mm

I 0-RINGS bolt and clean:OIL CONTROL JET

Replace.

Remove with 6mmbolt and clean.

6-6

.ft)

lr. . . .-I

6-7

VTECElectrical Connections

MAIN RELAY

PG2 A24

FLRl A7 (+

FUSES

tSPEED SENSOR

i+p

l3lfM&K ENGINE

( c2 VSP WARN Al3 0

( ES All '1 " "- EGR CONTROL SOLENOID VALVE

,

-

CHAMBER VOLUME CONTROLSOLENOID VALVE

m. . . .-I

MAPSENSOR

EETLESENSOR

IGNITIONTIMINGADJUSTER

ACCELERATORx

;E;M;NGLE

FRONTHEATED02 SENSOR

REARHEATED02 SENSOF

ALTERNATOR

1 r------- - -I r----- - -gF- - : I r-- --f ipm- -- -

D19 VCCl

D20 VCC2

D21 SGl

022 SO2

D17 PB

D5 PAOUT

IG No.1 A21

IG No.2 A22

IG No.3 B6

10 No.4 66

IG No.5 84

IG No.6 83

DllBTH I

I NEP C4

D15 TA AFSA Fl

D13TW I AFSB F3

I FAS Al6)D9 ACGF

A10 HTCNTF

014 02 F I VTSF F5

I VTSR F7

D4 KSF I

IGNITER UNITIGNITION COIL

FRONT SPOOL REAR SPOOLSOLENOID VALVE SOLENOID VALVE6"

*"

REAR FRONTKNOCK KNOCKSENSOR SENSOR

TERMINAL LOCATION

6-9

VTECB Troubleshooting -Self-diagnostic Procedures

1. Connect the Service Check Connector terminals with a jumper wire as shown (the Service Check Connector islocated under the dash on the passenger side of the car).

JUMPERWIRE

CHECK CONNECTOR

2. Note the CODE: the Check Engine light indicates a failure code by blinking frequency. The Check Engine light canindicate any number of simultaneous component problems by blinking separate codes, one after another. Problemcodes 1 through 9 are indicated by a individual short blinks. Problem codes 10 through 59 are indicated by aseries of long and short blinks. The number of long blinks equals the first digit, the number of short blinks equalsthe second digit.

Separate Problems:Short

4 n n= S e e P r o b l e m C O D E 1= See Problem CODE 3

v = See Problem CODE 13

2. Remove the CLOCK fuse (7.5 A) from the main relay box for 10 seconds to reset ECU.

NOTE: Disconnecting the CLOCK fuse also cancels the radio preset stations and the clock setting. Make note ofthe radio presets before removing the fuse so you can reset them.

CLOCKFUSE

III. Final Procedure (this procedure must be done after any troubleshooting)

(contd)

6-11

VTEC- Troubleshooting -Self-diagnostic Procedures (contd)

SELF-DIAGNOSISINDICATOR BLINKS

0

1

2

SYSTEM INDICATED PAGE

ECU 11-26

FRONT OXYGEN SENSOR 11-30

REAR OXYGEN SENSOR 11-30+ I I

3

5MANIFOLD ABSOLUTE PRESSURE (MAP SENSOR) 1 l-40

4 CRANK ANGLE A 11-46

6 ( COOLANT TEMPERATURE (TW SENSOR) 11-48

7 t THROTTLE ANGLE 11-60

9 No. 1 CYLINDER POSITION A (CYL SENSOR) 1 l-46

1 0 INTAKE AIR TEMPERATURE (TA SENSOR) 1 l-52

1 2 EXHAUST GAS RECIRCULATION SYSTEM (EGRI 11-128

I 1 3 1 ATMOSPHERIC PRESSURE IPA SENSOR) I 11-54 I1 4 ELECTRONIC AIR CONTROL (EACV) 11-70

1 5 IGNITION OUTPUT SIGNAL 11-56

1 6 FUEL INJECTOR 11-89

42 REAR OXYGEN SENSOR HEATER 1 l -32

43 FRONT FUEL SUPPLY SYSTEM 1 l -36

4 4 REAR FUEL SUPPLY SYSTEM 1 l -36

I 45 1 FRONT FUEL METERING I 11-38 II 46 1 REAR FUEL METERING I 11-38 II 47 1 FUEL PUMP I 1 l-99 I

I 54 1 CRANK ANGLE B I 11-46 II I

59 1 No. 1 CYLINDER POSITION B (CYL SENSOR) 1 l-46

0 If codes other than those listed above are indicated, verify the code. If the code indicated is not listed above, replacethe ECU.

0 The Check Engine light may come on, indicating a system problem, when, in fact, there is a poor or intermittent elec-trical connection. First, check the electrical connections, clean or repair connections if necessary.

0 The Check Engine light and D indicator light may come on simultaneously when the self-diagnosis indicator blinks 6, 7and 17. Check the PGM-FI system according to the PGM-FI control system troubleshooting, then recheck the D in-dicator light. If it comes on, see page 14-52.

0 The Check Engine light and TCS indicator light may come on simultaneously when the self-diagnosis indicator blinks3, 5, 6, 13, 15, 16, 17, 35 and 36. Check the PGM-FI system according to the PGM-FI control systemtroubleshooting, then recheck the TCS indicator light. If it comes on, see page 1 S-84.

l The Check Engine light does not come on when there is a malfunction in the A/T FI signal. However, when the two ter-minals of the service check connector are connected with a jumper wire and, the Check Engine light will indicate thecodes.

6-12

m. . . .--IIf the inspection for a particular failurebracket. Connect the ECU test

requires the ECU test harness, remove the seat back panels. Unbolt the ECUn check the system according to the procedure described for the appropriate.

code(s) listed on the following pages.

ECU

I

PANELS

DIGITAL MULTIMETER

TEST HARNESS07MAJ-PR70100

TEST HARNESS07LAJ-PT3OlOA

TERMINAL LOCATION

VTEC- Troubleshooting - Self-diagnostic Procedures (contd)

CAUTION:0 Puncturing the insulation on a wire can cause poor or intermittent electrical connections.0 For testing at connectors other than the ECU test harness, bring the tester probe into contact with the terminal from

the connector side of wire harness connectors in the engine compartment. For female connectors, just touch lightlywith the tester probe and do not insert the probe.

RUBBER SEAL TESTER PROBE

.TERMINAL

VTEC- Troubleshooting Flowchart - Spool Valve

@ (Front) or 4% (Rear) Check Engine indicates code 2 1Vaive circuit.

Disconnect the 2P connector fromthe spool va lve.

Check for continuity between YEL(Front) or BLUNEL (Rear) terminaland body ground.

(Front) or 5 1 (Rear): A problem in the Spool

YEL (Front) orBLUlYEL (Rear)

Replace the spool valve.

Y E S

IConnect the ECU test harness. F5 (Front)

Check for continuity between YEL(Front) or BLU/YEL (Rear) terminaland F5 (Front) or F7 (Rear)terminal .

F7 (Rear)

YEL (Front) orBLWYEL (Rear)

Does continuity exist 1

YES

N O Repair open in YEL (Front) orBLWYEL (Rear) wire betweenECU and spool valve connector.

(To page 6-16)

(contd)

6-15

VTEC-Troubleshooting Flowchart - Spool Valve (contd)

(From page 6-15)

(harness side) and body ground.J

Does continuity exist ?

N O

and recheck If symptomlindica-tion goes away replace the origi-

IYEL (Front) orBLWYEL [Rear)

-Troubleshooting Flowchart ----Oil Pressure Switch -

4 2 (Front) or 4 2 (Rear) Check Engine indicates code. 2 2 (Front), 5 2 (RealSwitch circuit.

p): A problem in the Oil Pressure

C

[

Disconnect the 2P connector fromthe oil pressure switch.

Check for continuity between BLU(Front) or BLWBLK (Rear) terminaland body ground.

I

1 011

GRN/VVHT (Front and Rear

BLU (Front) or BLU/BLK (Rear)

Does continuity exist 7

Y E S

Repair open in BLU (Front) orBLWBLK (Rear) wire between 2Pconnector and body ground.

Connect the ECU test harness.

F2 F4

II I

Check for continuity between BLU(Front) or BLU/BLK (Rear) terminaland F2 (Front) or F4 (Rear)terminal .

Does continuity exist ?Repair open in BLU (Front) orBLUlBLK (Rear) wire between

Y E SECU and 2P connector.

(To page 6-18) (contd)

6-17

-Troubleshooting Flowchart - Oil Pressure Switch (contd)

(From page 6-17)

11to normal operating temperatureStart the engine,and warm it up

WASHERReplace.

Is pressure below 49 kPa (0.5kg/cm 7 psi) 7 Y-

Inspect the spool valve.

\ /Y E S

Turn off the engine.Check for continuity between the,2 terminals on the oil pressureswitch.

I

,

Does continuity exist 7 Replace oil pressure switch.

Disconnect the 2P connector fromSPOOL VALVE

the spool valve.

Attach the battery positive termi-nal to the YEL (Front) or BLUlYEL

(To page 6-19)

ADAPTOR10 x 1 .Omm/

SEALING BOLT20N.m (2.0 kg-m, 14 lb-ft)

NOTE: Keep measuring time asshort as possible because engineis running with no load (within oneminute).

OIL PRESSURE SWITCH

E9. . . .-I

(From page 6-161

e

WASHERReplace.

ISEALING BOLT20Nm (2.0 kg-m, 14 lb-ft)

Note: Keep measuring time asshort as possible because engineis running with no load (within oneminute).

ADAPTOR

under above condi t ion.

Does continuity exist ?

N O

Replace oil pressure switch.

Substitute a known-good ECUand recheck. If symptomlindica-tion goes away replace the orlgl-nal ECU.

6-19

VTEC-Spool Valve Inspection

1 .2.

3.

Disconnect the 2P connector from the spool valve.Measure resistance between the YEL (Front) orBLU/YEL (Rear) terminal and body ground.

Resistance: approx 14-30 ohms

YEL (Front) orBLUlYEL (Read

If the resistance is within specifications, remove thespool valve assembly from the clinder head, andcheck the spool valve filter for clogging.l If there is clogging, replace the engine oil filter and

the engine oil.

SPOOL VALVEASSEMBLY

6x l.Omm12 N-m (1.2 kg-m, B lb-ft)

4. If filters are normal, push the spool valve with thefinger and check its movement.l If spool valve is normal, check the engine oil

pessure.

6x l.Omm12 N.m (1.2 kg-m, 9 lb-ft)

,Timing Belt m. . . .71Illustrated Index ?I

.NOTE:l Turn the crankshaft so that the No. 1 piston is at TDC 0, After installation, fill the engine with oil up to the

(page 6-25, 26) specified level, run the engine fbr more than 3

l Replace rubber seals if damaged or deteriorated. minutes, then check for oil leakage.

0 Prior to installing the cylinder head cover, apply a thin l When installing a new crankshaft;layer of liquid gasket to t,e mating surface of the / @tighten the crankshaft pulley bolt to 280N.m (28cylinder head cover and rubber seals to prevent the L kg-m, 203 lb-ft), @ loosen it, @ retighten it to 250

rubber seal from falling of. N-m (25 kg-m, 181 lb-ft).

4CAP NUT CAP NUT6x 1.0 mm 6xl.Omm

El? 1ON.m 11.0 kg-m, 7 lb-ft) lON-m (1.0 kg-m,. . _..CYLINDER HEAD COVI

,:(

RUBBER SEALSReplace when damaged

,. or deteriorated.

6x 1.0 mm12Nm (1.2 kg-m,9 lb-ft)

6x 1.0 mm

9 lb-ft)

TIMING BELTREAR MIDDLECOVER

\ WASHER and

,A \ - GROMMET

x 1.25 mm43N-m (4.3 kg-m+ id-ft)For adjustment only,do not remove.

LOWER COVER \\ \ GULL;AKS

, : . , ,,:^A.. --^ !. / _.i .ir.L, ., ,. .I:.

\

.;

T I M I N G B E L T J,nspection, page 6-22

6x 1.0 mm

SPECIAL BOLT16x 1.5 mm250N.m (2.5 kg-m,

Tightening torque fey

, :. Adjustment, page .6-22Replace every 9O;OOO miles(144,000 km) or 72 months.

Remove any oil. ., *. ~

-:, -as;.,,,. ., f*;~*;,, , -,L, . ? : :,. ., _. 1.TIMINGBELT

. ,T.,.

.

cCylinder Heads- Removal

NOTE: Engine removal is not required in this procedure.

CAUTION: To avoid damaging the cylinder heads, waituntil the coolant temperature drops below 38OC (lOOOF)before loosening the retaining bolts.

NOTE:l Inspect the timing belt before removing the

cylinder heads.l Turn the crankshaft so that the No. 1 piston is at

top-dead-center (page 6-25, 261.0 Mark ail emission hoses before disconnecting

them.

1.

2 .

Disconnect the negative terminal from the battery.

Remove the expansion tank cap.

Use care when removing the expansiontank cap to avoid scalding by coolant or steam.

3 .

4 .

5.

Raise the car.

Remove the right rear wheel/tire.

Remove the engine under guard, then remove thefront exhaust pipe A.

6 . Remove the exhaust pipe A.

CAUTION: Do not use air wrench or hammer forremoving the exhaust pipe A and the catalytic con-verter if the oxygen sensors are not to be removed.

GASKETSReplace.

SELF-LOCKING NUTS10 x 1.25 mm34N.m (3.4 kg-m, 25 lb-ft)Replace.

REAR EXHAUSTP I P E A

REAR EXHAUSTPIPE A

.

SELF-LOCKING NUTS10 x 1.25 mm34N.m (3.4 kg-m, 25 lb-ft)Replace.

GASKETSReplace.

7. Remove the under cover, then remove the waterpipe drain bolts and drain the coolant.

8. Attach the hoses to front and rear engine drainbolts, then loosen the bolts and drain thecoolant.0 Bleed air from the cooling system when install-

ing the cylinder heads (page 10-5).

CAUTION: Failure to comply with the bleedingprocedure could cause imperfect bleeding, whichmay result in severe engine damage.

9. Remove the engine oil cooler base assembly (page6-23).

IO. Lower the car.

11. Remove the strut bar (Page 5-I 9).

12. Remove the intake manifold plate and top cover(page 5-21).

13. Remove the throttle cable by loosening the locknut,then slip the cable and nut off the throttle bracketand throttle link (page 5-21).

NOTE:0 Take care not to bend the cable when removing

it. Always replace a kinked cable with new one.l Adjust throttle cable when installing (See Section

11).

6-28

m 14. Relieve fuel pressure (See Section 11).m Do not smoke while working on fuelsystem; keep open flame or spark away from workarea. Drain fuel only into an approved container.

15. Disconnect the fuel feed hose and the return hose(page 5-21).

16. Remove the ignition coil covers, the wire harnesscovers, the ignition coils and the connectors (page6-23).

17. Remove the water hoses, then remove the expan-sion tank (page 5-21).

18. Remove the breather hose, and the air cleaner case(page 5-22).

19. Remove the brake booster hose, the charcoalcanister hose and other hoses from the intakemanifold and throttle body (page 5-22).

20. Remove the emission control box (page 5-23).l Do not disconnect emission hoses.l Disconnect the three connectors before re-

moving.

m 21. Remove the connector, the terminal and the al-ternator.22. Disconnect the engine wire harness connectors, then

remove the harness clamps from the cylinder headand the intake manifold.

Front cylinder head:l CRANKICYL sensor connectorl A/C compressor magnetic clutch connector0 Oxygen sensor connector0 Ground cable terminall Ground terminall Three injector connectors (cylinders No.4, 5, and

6)l TA sensor connector0 Igniter connector0 Condenser connector0 Oil pressure sensor connector (oil pressure gauge)0 Spool valve connectorl Oil pressure switch connector (VTEC)0 TW sensor connector (for emission)0 Temperature sender unit connectorl Pedal sensor connector (throttle body)0 TW sensor connector (for radiator fan)

m

Rear cylinder head:l Oil pressure switch connector (oil cooler base)0 Oxygen sensor connectorl Three injector connectors (cylinders No. 1, 2, and

3)0 EACV connectorl Knock sensor connectorl Step motor connector (throttle body)l Throttle sensor connector0 Spool valve connectorl Oil pressure switch connector (VTEC)0 Igniter connector0 Ground terminal

IGNITER CONNECTORS

nSTEP MOTORCONNECTOR

PEDAL SENSOR THROTTLE SENSORCONNECTOR CONNECTOR

(conid)

6-29 ,

-Removal (contd)

23. Remove the EGR pipe and the intake manifold as-sembly.

NOTE: Fill the cylinder head intake ports with cleanshop towels to prevent foreign materials from get-ting into the cylinders.

EGR PIPEMOUNTING BOLT8x 1.0 m m12N.m (1.2 kg-m,9 lb-W

8x 1.25 m m22N.m (2.2 kg-m,1 8 lb-W

PCV HOSERemove.

INSECTOR CONNECTOR(No.4 CYLINDER)

I

\TA SENSORCOYNECTOR I

GROUNDCABLE

GROUtiD CABLE

I8x 1.0 mm12Nm (1.2 kg-m,9 lb-ftl

\INJECTORCONNECTOR(No.1 CYLINDER)

INTAKE MANIFOLDGASKETReplace.

EGR PIPEGASKETReplace.

4

(_-

e

24. Remove the side engine mount, then push it into theside mounting bracket housing of the body (page5-26).

25. Remove the transmission mount.

26. Remove the alternator bracket stiffener (page 6-24).

27. Disconnect the knock sensor connectors, then re-move the wire holder.

6x 1.0 mm12Nm (1.2 kg-m, 9 lb-ft)

I KNOCK SENSORWIRE HOLDER

28. Remove the heater hose and the water hoses.

WATER HOSES

29. Remove the water passage.

PIPE

6x 1.25 mm22N-m (2.2 kg-m, 16 lb-ft)

30. Remove the cylinder head covers.

31. Turn the crankshaft so that the No. 1 piston is at top-dead-center (page 6-25, 26),,

A>:

32. Install the attachment under the engine, then tilt theengine approximately 5O using a jack (page 6-24)

33. Remove the alternator bracket.

:. t9x 1.25,mm22N.m.(2.2 kg-m, 16 lb-ft)

,

ALTERNATOR

i

r:

-? ;

\-

6-31

Cylinder Head- Removal (contd)

NOTE: Removal of the following items is not necessaryif only the rear cylinder head is going to be removed.0 A/C adjusting pulley and A/C belt0 Timing belt lower coverl Crankshaft pulley

34. Remove the A/C adjusting pulley and belt.

33. Remove the dipstick pipe mounting bolt, then re-move the front and rear timing belt middle covers.

35. Remove the crankshaft pulley, then remove the tim-ing belt lower cover.

36. Loosen the timing belt adjusting bolt 180 andrelease the belt tension.NOTE: Push the tensioner to release tension fromthe belt, then retighten the adjusting bolt.

ALiJUSTlNG BOLTDo not remove.Loosen it 1 80.

37. Remove the timing belt from the pulleys.

CAUTION: Do not crimp or bend the timing beltmore than 90 or less than 25 mm (1 in) in diameter.-;y-.

CAUTION: Do not crim@& bend the timing belt. .ifiore than 90 or less than 25mm (I inl in diameter.

38. Remove the cam pulleys.

RETAININGBOLTS

CAM PULLEYS

39. Remove the front and rear timing belt cover plates.

REAR TIMING BELTCOVER PLATE

RUBBER SEALS

FRONT TIMING BELTCOVER PLATE

6-32

ra 40. Loosen the valve locknuts, backed off the adjust-ing screw.

41. Remove the cam holder pipes, the cam holdersand the camshafts.

CAM HOLDERPIPES

FRONT INTAKECAMSHAFT

RUBBER SEAL

VOIL SEALSReplace.

CAMSHAFT

42. Screw a 5 mm bolt into each rocker shaft orifice,then pull out the rocker shaft orifices.

fl

ROCKER SHAFT 5 mm BOLT

43. Remove the spool valve assemblies.

44. Remove the sealing bolts.

EALING BOLT

BOLT

45. Bundle the rocker arms with a rubber band toprevent them from separating.

46. Screw a 12 x 1.25 mm bolt into each rockershaft. Remove the rocker arms while slowly pull-ing the rocker shafts out of the cylinder headstoward the transmission.

ROCKER ARMRUBBER BAND

ASSEMBLYS

I /

*I

12 mm BOLT

(contd)

6-33;

Cylinder Heads- Removal (contd)

47. Disconnect the connectors and remove the enginewire harness.

48. Remove the cylinder head bolts, then remove thecylinder heads.CAUTION: To prevent warpage, unscrew the boltsin sequence 113 turn at a time; repeat the sequenceuntil all bolts are loosened.

CYLINDER HEAD BOLTS LOOSENING SEQUENCE

NOTE: Separate the cylinder head from the block witha flat blade screwdriver as shown.

49. Remove the front and rear exhaust manifold covers,then remove the front and rear exhaust manifolds.CAUTION:l Remove the oxygen sensors before removing the

exhaust manifolds.l Do not use air wrench or hammer for removing

the exhaust manifolds if the oxygen sensors arenot to be removed.

Rocker Arms and Shafts5 I

*ea.-I

Locations

CAUTION: After installing the locker shaft orifice, try to turn the locker shaft to make sure that the orifice has beeninserted in the hole of lockershaft correctly. If the orifice is in place, it should not turn.

NOTE:l Identify parts as they are removed to ensure reinstallation in original locations.0 Inspect rocker shafts and rocker arms (pages 6-l 3 and 141.0 Rocker arms must be installed in the same position if reused.s Install the rocker arms after torquing the cylinder head bolts.

3 Prior to reinstalling, clean all the parts in solvent, dry them and apply lubricant to any contact surfaces.Front Cylinder Head:

SEALING BOLTS 20 mm60N.m (6.0 kg-m, 43 lb-W

EXHAUST ROCKER

EXHAUST ROCKER ARM ASSEMBLIESNo1.6 No.5 Nd.4

RUBBER BAND

RUBBER BAND

INTAKE ROCKER ARM ASSEMBLIES CYLINDER NUMBER

Rear Cylinder Head:Nd.3 No.2

.1 CYLINDER NUMBER

ISEALING BOLTS 20 mm60N.m (6.0 kg-m, 43 lb-ft)

RUBBER BAND

VU&HERS EXHAUST ROCKER -----!\--__._ -__----Replace. SHAFT

RUBBER BAND

Nd.3 Nd.2 Nh.1

EXHAU;T ROCKER ARM ASSEMBLIES ., ,(c,..

Rocker Arms and Lost Motion Assemblies- Inspection

NOTE: When reassembling the primary rocker arm, care-fully apply air pressure to the oil passage of the rockerarm.

PRIMARY ROCKER ARM

SECONDARYROCKER ARM

PISTONS

1 . inspect the rocker arm piston. Push it manually.- If it does not move smoothly, replace the rocker

arm assembly.

PRIMARY

Check piston movenent

NOTE:0 Apply oil to the pistons when reassembling.0 Bundle the rocker arms with a rubber band.to pre-

2. Remove the lost motion assembly from the cylinderhead and inspect it. Pushing it gently with the fingerwill cause it to sink slightly. Increasing the force onit will cause it to sink deeper.- If the lost motion assembly does not move

smoothly, replace it.

Push

4 vent them from separating.

LOST MOTION ASSEMBLY

I;

Rocker Arms and Shafts- Clearance

a Measure both the intake rocker shafts and exhaust rockershafts.

1. Measure diameter of shaft at first rocker location.

+- MJCROMETER

Surface shbuld be smooth.

2. Zero gauge to shaft diameter.

MICROMETER

3. Measure inside diameter of rocker arm and check forout-of-round condition.

Rocker Arm Radial Clearance:Service Limit: 0.08 mm (0.003 in.)

Inspect rocker armface for wear.

Repeat for all rockers. ..-.: ,I- If over limit, replace rocker shaft and all over-

tolerance rocker arms.I

NOTE: If any rocker arm needs replacementj~refilaceall three rocker arms in that set (primary,mid, andsecondary).

Camshafts- ,lnspection

NOTE:l Do not rotate the camshaft during inspection.l Remove the rocker arms and rocker shafts.1. Put the camshafts, the cam holders the holder pipes

on the cylinder head, and then tighten the bolts tothe specified torque.NOTE: Apply clean engine oil to 8 mm bolt threads.Specified torque:@-@I 8mmx1.25mmbolts:

22N.m (2.2 kg-m, 16 lb-ft)0-a 6mmxl.Omm bolts:

ION-m (1.0 kg-m, 7 lb-ft)CAM HOLDER BOLTS TORQUE SEQUENCE

FRONT:

REAR:

2. Seat the camshaft by pushing it toward left end ofcylinder head.

3. Zero the dial indicator against the left end, then pushthe camshaft back and forth, and read the end play.Camshaft End Play:Standard (New): 0.05-0.15 mm

(0.002-0.006 in.)Service limit: 0.5 mm (0.02 in.)

4. Remove the bolts, then remove the cam holders fromthe cylinder head.-... Lift camshaft out of cylinder head, wipe clean,

then inspect lift ramps. Replace camshaft if lobesare pitted, scored, or excessively worn.

- Clean the camshaft bearing surfaces in thecylinder head, then set camshaft back in place.

5.- lnse,rt plastigage strip across each journal.Insta!l..the cam holders, and then tighten the boltsto the specified torque, as shown in the left columnon this page.

6. Remove the cam holders%d measure widest por-tion of plastigage on each journal.Camshaft Bearing Radial Clearance:Standard (New):0.050-0.089 mm

( 0 . 0 0 2 - 0 . 0 0 4 i n . 1Service Limit: 0.15 mm (0.006 in.)

PLASTIGAGE STRIP

eE3. . . .-I

7. If camshaft bearing radial clearance is out oftolerance:- And camshaft has already been replaced, you

must replace the cylinder head.- If camshaft has not been replaced, first check to-

tal runout with the camshaft supported on V-blocks.

Camshaft Total Runout:Standard (New): 0.015 mm (0.0005 in)Service Limit: 0.030 mm (0.0012 in)

0- If the total runout of the camshaft is within toler-

ance, replace the cylinder head.- If the total runout is out of tolerance, replace the

camshaft and recheck. If the bearing clearanceis still out of tolerance, replace the cylinder head.

8. Check cam lobe height wear.

Cam lobe height standard (New):M/TI

! INTAKE j EXHAUSTPRIMARY 37.086 mm 36.559 mm

(I .4601 in) (I .4393 in)

MID 38.037 mm 37.398 mmf 1.4975 in) (I .4724 in)

SECONDARY 37*326 mm 36.741 mm(I .4695 in) .( 1.4465 in)

r INTAKEPRIMARY 37.266 mm

(1.4672 in)

MID 37.655 mm(1.4825 in)

37.504 mmSECoNDARY (1.4765 in)

EXHAUST

36.559 mmIl.4393 in)

37.398 mm(I .4724 in)

36.741 mm(1.4465 in)

Check this area for wear.

Cam positionP : Primary M: Mid S : Secondary

Valves and Valve Seals

c_

- Replacement

NOTE: Identify valves and valve springs as they are re-moved so that each item can be reinstalled in its originalposition.

1 .

2 .

Using an appropriate-sized socket and plastic mallet,lightly tap the valve retainer to loosen the valve keep-ers before installing the valve spring compressor.

PLASTIC MALLET

Install spring compressor. Compress spring and re-move valve keeper.

VALVE SPRINGCOMPRESSORATTACHMENT

VALVE SPRINGCOMPRESSOR ATTACHMENTEXTENSION

IIVALVE SPRING COMPRESSORSnap-on CF711

-

3. Install the special tool as shown.

VALVE SEAL\

COMMERCIALLY AVAILABLEVALVE GUIDE SEAL REMOVERLISLE P/N 57900

S EPU

4. Remove the valve guide seal.

COMMERCIALLY AVAILABLEVALVE GUIDE SEAL REMOVERLISLE P/N 57900

A------, -----IrrL-V

Intake Valve DimensionsA Standard (New): 34.9-35.1 mm

(I .374- 1.382 in18 Standard (New): 111.05-111.40 mm

, r (4.372-4.388 in)C Standard (New): 5.475-5.485 mm

(0.2158-0.2159 in)C Service Limit: 5.445 mm (0.2144 in)D Standard (New): 1.05-1.35 mm

(0.041-0.053 in)D Service Limit: 0.85 mm (0.033 in1

Exhaust Valve DimensionsA Standard (New): 29.9-30.1 mm

(1.177-1.185 in)8 Standard (New): 109.80-109.90 mm

(4.315-4.327 in)C Standard (New): 5.45-5.46 mm

(0.2148-0.2150 in)C Service Limit: 5.42 mm (0.2134 in1D Standard (New): 1.65- 1.95 mm

(0.065-0.077 in)D Service Limit: 1.45 mm (0.057 in1

Cylinder Heads ml e.*-I- Warpage

NOTE: If camshaft bearing clearances (page 6-38) arenot within specification, the head cannot be resurfaced.

If camshaft bearing radial clearances are within specifi-cations, check the head for warpage.

s If warpage is less than 0.05 mm (0.002 in.) cylinderhead resurfacing is not required.

l If warpage is between 0.05 mm (0.002 in.) and 0.2mm (0.008 in.), resurface cylinder head.

l Maximum resurface limit is 0.2 mm (0.008 in.) basedon a height of 151 mm (5.945 in).

PRECISION STRAIGHT EDGE&, \

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Measure along edges, and 3 ways across center.

Cylinder Head Herght; 1;Standard (New): 150.95- 151.05

(5.943-5.947 in1Service Limit: 150.8 mm (5.937 in)

Valve Seats- Reconditioning

1 . Renew the valve seats in the cylinder head using avalve seat grinder.

NOTE: If guides are worn (page 6-431, replace them(page 6-44) before grinding the valve seats.

2. Carefully grind a 45O seat, removing only enoughmaterial to ensure a smooth and concentric seat.

3. Bevel the upper edge of the seat with the 30 stoneand the lower edge of the seat with the 60 stone.Check width of seat and adjust accordingly.

4. Make one more very light pass with the 45O stoneto remove any possible burrs caused by the otherstones.

Valve seat Width:Standard: IN 0.80- 1 .OO mm (0.031-0.039 in)

EX 1.25-1.55 mm (0.049-0.061 in.)Service Limit: IN 1.5 mm (0.059 in)

EX 2.0 mm (0.079 in)

Seat Width60

5 . After resurfacing the seat, inspect for even valveseating: Apply Prussian Blue compound to the valveface, and insert valve in original location in the head,then lift it and snap it closed against the seat sever-al times.

ACTUAL /.

VALVESEAT Y

/PRUSSIAN BLUE COMPOUND ;

6. The actual valve seating surface, as shown by theblue compound, should be centered on the seat.l If it is too high (closer to the valve stem), you

must make a second cut with the 60 stone tomove it down, then one more cut with the 45Ostone to restore seat width.

l If it is too low (closer to the valve edge), you mustmake a second cut with the 30 stone to moveit up, then one more cut with the 45O stone torestore seat width.NOTE: The final cut should always be made withthe 45O stone.

7. Insert intake and exhaust valves in the head andmeasure valve stem installed height.Valve Stem Installed Height (IN and EX):Standard (New): 41.55-42.35 mm

(I .6358- 1.6673 in)Service Limit: 42.435 mm (1.6707 in)

INSTALLED HEIGHT

8. If valve stem installed height is over the service limit,replace valve and recheck. If still over the servicelimit, replace cylinder head; the valve seat in the headis too deep.

6-42I

Valves r!ll eeo-I. Valve Movement

Measure the guide-to-stem clearance with a dial indica-tor while rocking the stem in the direction of normal thrust(wobble method).

Intake Valve Stem-to-Guide Clearance:Standard (New): 0.0125-0.0275 mm

(0.0005-0.0011 in)Service Limit: 0.08 mm (0.003 in1

Exhaust Valve Stem-to-Guide Clearance:Standard (New): 0.025-0.04 mm

(0.001-0.0016 in)Service Limit: 0.055 in (0.0022 in)

Valve extended IO mm out from seat.

l If measurement exceeds the service limit, recheckusing a new valve.

0 If measurement is now within the service limit,reassemble using a new valve.

l If measurement still exceeds limit, recheck usingalternate method below, then replace valve andguide, if necessary.

NOTE: An alternate method of checking guide to stemclearance is to subtract the O.D. of the valve stem, meas-ured with a micrometer, from the I.D. of the valve guide,measured with an inside micrometer or ball gauge.Take the measurements in three places along the valvestem and three places inside the valve guide. The differ-ence between the largest guide measurement and thesmallest stem measurement should not exceed the serv-ice limit

Intake Valve Stem-to-Guide Clearance:Standard (New): 0.025-0.055 mm

(0.001-0.002 in)Service Limit: 0.08 mm (0.003 in)

Exhaust Valve Stem-to-Guide Clearance:Standard (New): 0.05-0.08 mm

(0.002-0.003 in1Service Limit: 0.11 mm (0.004 in)

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6-43

Valve Guides. Replacement

1 . As illustrated, in the removal steps of this procedureuse a commercially-available air-impact driver at-tachment which may need to be modified to fit thediameter of the valve guides. In most cases, thesame procedure can be done using Valve GuideDrivers and a conventional hammer. Tool numbersare at the end of this procedure.

VALVE GUIDE DRIVERI 5 . 3 mm

(0.21 in)

=cll5! FE

2.

3.

87 mm-- l -

57 mm 4 1(3.43 in.) (2.24 in.) 1 0 . 8 mm

(0.42 in)

Select the proper replacement guides and chill themin the freezer section of a refrigerator for about anhour.

Use a hot plate or oven to evenly heat the cylinderhead to 1 50C J3OOF). Monitor the temperaturewith a cooking thermometer.

CAUTION:0 Do not use a torch; it may warp the head.a Do not get the head hotter than 150C (300F);

excessive heat may loosen the valve seats.0 To avoid burns, use heavy gloves when handling

the heated cylinder head.

4. Use the driver and an air hammer working from thecamshaft side to drive the guide about 2 mm towardsthe combustion chamber. This will knock off someof the carbon and make removal easier.

VALVE GUIDE DRIVER07742-0010100

CAUTION:a Always wear safety goggles or a face shield when

using the air hammer.l Hold the air hammer directly in line with the valve

guide to prevent damaging the driver.

5. Turn the head over and drive the guide out towardthe camshaft side of head.

If a valve guide still wont move, drill it out with a5/16 inch bit, then try again.

CAUTION: Drill guides only in extreme cases: youcould damage the cylinder head if the guide breaks.

-*-6. Remove the new guide(s) from the refrigerator, one

at a time, as you need them.\

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6-44

7. Slio a 6 mm steel washer and the correct driver at-tachment over the end of the driver (The washer willabsorb some of the impact and extend the life of thedriver).

DRiVER 6 mm tiASHER ATTACHMENT

8. Install the new guide(s) from the camshaft side ofthe head; drive each one in until the attachment bot-toms on the head. If you have all twelve guides todo, you may have to reheat the head one or twomore times.

VALVE GUIDEDRIVER, 5.5 mm07742-0010100

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ATTACHMENT

NOTE: Valve guide replacement can be performedwith this special tool.

Removal and InstallationVALVE GUIDE DRIVER07742-0010100Valve Guide Installed Height:Intake: 13.75-14.25 mm (0.541-0.561 in)Exhaust: 13.75-14.25 mm (0.541-0.561 in)

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-Valve Guide Reaming

NOTE: For new valve guides only.

1 . Coat both reamer and valve guide with cutting oil.

2. Rotate the reamer clockwise the full length of thevalve guide bore.

3. Continue to rotate the reamer clockwise whileremoving it from the bore.

4. Thoroughly wash the guide in detergent and waterto remove any cutting residue.

5 . Check clearance with a valve (page 6-43).- Verify that the valve slides in the IN, EX valve

guides without exerting pressure.

REAMER HANDLE

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VALVE GUIDEREAMER, 5.5 mm

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Turn reamer inclockwise direction

6-45T.

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Valve Springs and Valves-Valve Spring and Valve Seal Installation Sequence

NOTE: Exhaust and intake valve seals are NOT interchangeable.

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VALVE KEEPERSINTAKE VALVE SPRING (M/T only)

VALVE SPRING

@a9RETAINER

-VALVE SPRING/ ----

.- -. . . .._ -

EXHAUST VALVE SEAL(BLACK SPRING)Replace.

\NOTE: Place the end ,of valve /spring with closely WOUJ-ICJ coilstoward the cylinder head.

INTAKE VALVE SEAL(WHITE SPRING)Replace.

; 6 -46 ,. i,

SPRING SEATNOTE: Install the valve spring seatsbefore instal l ing the valve seals.

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Cylinder Heads El0.~0.- I

Valve Installation

l When installing valves in cylinder head, coat valvestems with oil before inserting into valve guides, andmake sure valves move up and down smoothly.

l When valves and springs are in place, lightly tap theend of each valve stem two or three times to ensureproper seating of valve and valve keepers (use ham-mer handle bottom).

HAMMER HANDLEBOTTOM

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,lnstallation

Install the cylinder heads in the reverse order of removal:l Always use new head gaskets.l Cylinder heads and engine block surface must be

clean.l Turn the crankshaft so that No. 1 piston is at TDC

(page 6-26).

1; Install the front and rear exhaust manifolds to eachcylinder head, then tighten the self-locking nuts ina criss-cross pattern in two or three steps, beginningwith the inner nut.0 Apply oil to the self-locking nut threads.l Always use new exhaust manifold gaskets.CAUTION:l Install the oxygen sensors after installing the ex-

haust manifolds.0 Do not use air wrench for tightening the self-

locking nuts if the oxygen sensors are not to beremoved.

2. install the exhaust manifold covers.

Front:

OXYGEN SENSOR45 N-m (4.5 kg-m, 33 lb-ft)Be careful not to damage.

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SELF-LOCKING

34 N-m (3.4 kg-m,25 lb-ft) ...Replace.

--vEXHAYST MANIFOLDSHROLjD

~~~,&$+ _ \ ;-;\; 22 N*m (2.2 kg-m, .

b. 16 lb-ft)

Cylinder Heads- Installation (contd)

Rear:

8x 1.25 mm22 N*m (2.2 kg-m,

OXYGEN SENSOR45 N-m (4.5 kg-m,33 lb-ft)Be careful not to damage./

REAR EXHAUSTMANIFOLD

LOCKING NUTS8x 1.25 mm34 N-m (3.4 k