MERCURY OUTBOARDS -

M O D E L S 1966 THRU 1972

Black can and

& Know the channel markers t o follow a SAFE and CON-

5: FIDENT course.

Obstruct~on When returning, keep the red buoys on your right; black

spar buoys marker buoys on your left.

CI? Black-and-white vertically striped buoys indicate middle ____ of channel; always pass close to them, either side. Red nun and Mid-channe' Black-and-red horizontally striped buoys indicate ob- spar buoys buoy

struction; gb;e them a wide berth.

Keep practicing water SAFETY night-and-day by observing

the following simple rules:

Do not operate boat near swimmers. skin divers or

fishermen.

Keep clear on' sailing craft and rob oats. yielding rig

way.

to the right; show courtesy at all times. WHITE STERN LIGHT

VISIBLE 360"

rine, Fond dw L,ac, Wisconsin 54935 U.S.A. Litho in U.S.A.

TABLE of C O N T E N T S Page

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Section 1 . General Information . . . . . . . . . . . . . . . . . . . . . . 5

1.1 . Important . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1.2 . Directional References . . . . . . . . . . . . . . . . . . . . . . 5 1.3 . Periodic Checkup . . . . . . . . . . . . . . . . . . . . . . . . . 5 1 4 . Write a Letter of Explanation . . . . . . . . . . . . . . . . . . 5

. . . . . . . . . . . . . . . . . . . . . 1.5 Service Recommendations 5 1-6 . Serial Number . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

. . . . . . . . . . . . . . . . . . . . . 1.7 Motor and Boat Insurance 6 . . . . . . . . . . . 1.8 . Recording Electric Starting Key Number 6

Section 2 . Motor Installation . . . . . . . . . . . . . . . . . . . . . . . 6 2.1 . Outboard Motor Mounting . . . . . . . . . . . . . . . . . . . 6

2.2 . T i l t Pin Adjustment . . . . . . . . . . . . . . . . . . . . . . . 8 . . . . . . 2.3 . Tilt-Up and Shallow Water Trol l Lever Operation 9

2.4 . Ti l t Stop Lever . . . . . . . . . . . . . . . . . . . . . . . . . 10 2 5 . Conditions Affecting Operation . . . . . . . . . . . . . . . 10 2-6 . Adjusting Co-Pilot . . . . . . . . . . . . . . . . . . . . . . . 10

Section 3 . Propeller Recommendations . . . . . . . . . . . . . . . . 1'1 3.1 . Propellers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.2 . Propeller Selection . . . . . . . . . . . . . . . . . . . . . . . 11 3.3 . Installing Propeller . . . . . . . . . . . . . . . . . . . . . . . 11

. . . . . . . . . . . 6 C y l . Models and 4 X y l . Merc 800-650 112 Merc 650 (3Cy l . 7972) . . . . . . . . . . . . . . . . . . . . 12

Merc 5 0 M 8 2 4 0 ( 2 4 3 l . 1 and 350 . . . . . . . . . . . . . 13 Merc 200-1 10-75-40-39 . . . . . . . . . . . . . . . . . . . . 13

3 4 . How to Remove Propeller . . . . . . . . . . . . . . . . . . . 13

3.5 . Propeller Repair . . . . . . . . . . . . . . . . . . . . . . . . 93

Section 4 . Accessories Installation . . . . . . . . . . . . . . . . . . . 1 4.1 . Remote Control Attachment (Single Lever) . . . . . . . . . 1

A l l 1966-thru-1972 Models. except Merc 200-110-75-

6040-39 . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Merc 200-1 10-75-60-40-39 . . . . . . . . . . . . . . . . . 1

4.2 . Dual Motor Installation . . . . . . . . . . . . . . . . . . . . 1 Section 5 . Fuel Mixture and Fuel System . . . . . . . . . . . . . . . 1

5.1 . Installing Fuel Tank . . . . . . . . . . . . . . . . . . . . . . 1

5.2 . Rewmmended Fuel Mixture . . . . . . . . . . . . . . . . . 1 5.3 . Correct Fuel Mixing Procedure . . . . . . . . . . . . . . . . 1, 5 4 . Importance of Consistent Fuel Mixtures . . . . . . . . . . . 1;

Section 6 . Starting and Stopping . . . . . . . . . . . . . . . . . . . . 1', 6.1 . Description . Electric Starting . . . . . . . . . . . . . . . . . l! 8 2 . Electric Starting Procedure . . . . . . . . . . . . . . . . . . I! 6 3 . Emergency Starting Procedure (Elec . Start Models) . . . . 2' 6 4 . Manual Starting Procedure (Manual Starting Models) . . . 2: 6 5 . Stopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2. 6-6 . Removing Motor from Boat . . . . . . . . . . . . . . . . . . 2:

Section 7 . Opwation . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 7.1 . Throttle and Shift . . . . . . . . . . . . . . . . . . . . . . . 21

7.2 . Don'ts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 7.3 . Adjustable T im Tab and Galvanic Corrosion lnhibotor . . 25 7 4 . Power Tr im Operation . . . . . . . . . . . . . . . . . . . . . 2: 7-5 . How to Tell Whether Water Pump Is Operating . . . . . . . 27 745 . Cavitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 7.7 . Shallow Water Operation . . . . . . . . . . . . . . . . . . . 28

. . . . . . . . . . . . . . . . . . . . . 7 8 Operation in Sak Water 28

Page 1

Section 8 . Fuel System Maintenance . . . . . . . . . . . . . . . . . . 28 . . . . . . . . . . . . . . . . . . . . . . . . 8.1 Removing Cowling 28

. . . . . . . . . . . . . . . . . . . . 8.2 . Carburetor Adjustment 30 8.3 . Approx~mate Initial Setting . . . . . . . . . . . . . . . . . . 33

. . . . . . . . . . . . . . . . . . . . 8 4 . Low Speed Adjustment 31

8 5 . Servicing Fuel Tank Filter . . . . . . . . . . . . . . . . . . . 31

. . . . . . . . . . . . . . . . . . 8.6 . Servicing Motor Fuel Filter 31

. Section 9 Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . 32 . . . . . . . . . . . . 9.1 . Mercury Outboards Lubrication Chart 32

9.2 . Lower Drive Unit Lubrication . . . . . . . . . . . . . . . . 33 Section 10 . Ignition Maintenance . . . . . . . . . . . . . . . . . . . . 35

10.1 . Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 10.2 . Servicing Spark Plugs . . . . . . . . . . . . . . . . . . . . . . 35 10.3 . Battery . Electric Start Models . . . . . . . . . . . . . . . . 35

10.4 . Maintenance of Battery . . . . . . . . . . . . . . . . . . . . 36

10.5 . Winter Storage Care of Battery . . . . . . . . . . . . . . . . 36 10.6 . Electrical Accessories Connections . . . . . . . . . . . . . . 36

Section 11 . Special Care Required . . . . . . . . . . . . . . . . . . . 37 11.1 . Periodic Inspection . . . . . . . . . . . . . . . . . . . . . . . 37

11 .2 . Preparation for Storage . . . . . . . . . . . . . . . . . . . . 37

11.3 .At tent ion Required following Operation in Salt Water

or Silt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

11 4 . Attention Required following Complete Submersion . . . . 39

Section 12 . Trouble Chart . . . . . . . . . . . . . . . . . . . . . . . . 41

. 411 informntion herein Ifins in effect when this hook war printed . . Wercury .I.lnrinc?. whose policy is one o f continuous improvement, reserves the right to discontinue models at any time or to chnnge specifications or designs without notice and without incurring ohligatio n

07047 Figure l . Merc 402 Model

Page 2

G E N E R A L SPECIFICATIONS - 1966 thru 1972 M E R C M O D E L S

Year

1 lCUJl Merc Model HP Displ

Full

Throttle

RPM Range

5000-5400 5000-5400 4500-5500 4500-5500 5000-5400 5000-5400 4500-5500 4500-5500 5000-5400 5000-5400 4500-5500 5000-5400 5000-5400 4800-5500 4800-5200 4800-5300 4800-5300 4800-5300 5200-5600 5200-5600 5200-5600 4800-5500

Bore

2" 2" 2" 2 "

1-314" 1-314"

2" 2" 2" 2" 2"

2-9/16" 2-911 6" 2-9/16''

3" 3"

2-718" 2-718" 2-9/16'' 2-9/16" 2-9/16" 2-7 I*

Stroke

1-314" 1-314" 1-314" 1-314" 1-112" 1-1 12" 1-314" 1-314" 1-314" 1-314" 1-314" 2-1 18" 2-1 18" 2-1 18" 2.3" 2.3''

2-911 6" 2-9/16" 2-1 18" 2-1 18" 2-1 18" 2-1 I* -

Point

Settin - .020" .020u .020" ,020'' .020" .020" ,020'' .020" .020" .020" ,020'' 020" "020" ,020'' ,020" ,020'' None None 010*,{ 01 0.. ! Vone \one

Metric Conversion: 1 "= 2 5 . 4 ~ 1 ~ 1 Cu. In. = 1 6 . 8 ~ ~

Page 3

Year

I966 1967 1968-69 1970-7 1 1972 1969 1970-7 3 1972 1966 1966 I967 1968-69 I968 1969 I966 1966 I967 1970-71 1972 1968-69 1968-69

1970-71 1972

Merc Model

650 650s

650SS 650

650 (3-Cvl.) 800 800 800 950

950SS 950SS 1 000ss IOOOBP

1000 Super BP 1100

1 1 0 0 s 1 1 OOSS

1150 1150

1250SS 1250BP and

Super BP 1350 1400

,VOTE: Chonpwn L-77V may be used in place of AC Charnpwn L78V may be used in piuce of AC-V4OFFK.

Bore

2-718" 2-1 511 6' 2-1 511 6' 2-1 511 6' 2.87"

2-718'' 2-718" 2.87"

2-718" 2-718'' 2-718" 2-718'' 2-718'' 2-718" 1-1 511 6" ?-I 511 6' !-I 511 6" 2-718'' 2.87"

2-718" 2-718"

2-7i8" 2.87"

Stroke

2.3" 2.3" 2.3" 2.3"

2-911 6" 2-9/16" 2-9/16" 2-9/16"

2.3" 2.3" 2.3" 2.3" 2.3" 2.3" 2.3" 2.3" 2.3"

2-9/16" 2-911 6" 2-911 6" 2-9/16'

2-9/16" 2-9/16'" -

Spark

Plug Type

:hampion J4. :hampion L4 AC-V40F FM AC-V4OF F M AC-V40F FM AC-V40FFM AC-V4OF FM AC-V40FFM :hampion L4 AC-V40F FM AC-V40FFM AC-V40FFM AC-V40F FM AC-V40FFM :hampion L4 AC-V40FFM AC-V4OFFM 4C-V40FFM 4C-V4OF FM 4C-V4OFFM 4C-V40FFM

4C-V4OFFM 4C-V40FFM

Plug h t i w - ,025'' ,030" None None None None None None ,030" None None None None None .030" None None None None None None

None None

Ignition

TY P

Kiekhaefer Kiekhaefer

Thunderbolt Thunderbolt Thunderbolt Thunderbolt Thunderbolt Thunderbolt Kiekhaefer Kiekhaefer Kiekhaefer

Thunderbolt Thunderbolt Thunderbolt Kiekhaefer Kiekhaefer Kiekhaefer

Thunderbolt Thunderbolt Thunderbolt Thunderbolt

Thunderbolt Thunderbolt

Point Setting

.010" Or' ! None None None None None None

45' Dwell 90' Dwell

None None None None

90' Dwell 45' Dwell

None None None None None

None None

Metric Conversion: I " = 25.4mm; 1 Cu. In. = 1 6 . 4 ~ ~ Page 4

Section I - General hformation 1-1. IMPORTANT 1. Clean filters on carburetor(s) and fuel system. A standard one-y ear warranty, covering material and workmanship, was 2. Check lubricant in lower unit. issued by your dealer for the outboard motor (not used commercially) 3. Check water pump operation. when sold new. Replacement parts on service work after one year carry 4. Lubricate control linkage, distributor or magneto adaptor (4 and a 3 month warranty. 6-cylinder models) and swivel pin.

5. Lubricate reverse lock lever.

1-2. DIRECTIONAL REFERENCES 6. Cheek and tighten all nuts and bolts. 7. Test and adjust motor after completing checkup.

Front of boat is bow; rear is stem. Starboard is right side; port is left side. In this book. all directional references are given as they appear when viewing boat from stern, looking toward bow. (Figure 2 ) To find the Authorized Mercury Senice

S T A R B O A R D facilities in your locality or when traveling, refer to the classified pages in the local te lephone directory under "Outboard Motors ".

14. WRITE a LETTER of EXPLANATlON If writing to the factory, include the following information: 1) Serial number, 2) model number, 3) date purchased, 4) dealer from wbom purchased, 5) number of hours motor has been operated, 6 ) details of trouble experienced, 7) dates of previous correspondence, 8) boat make and size, 9 ) propeller pitch and number of blades or part number, and 10) normal use and approximate load.

P O R T {REAR) References (LEFT) No Motor I s l o Be Shipped to the Factory without Specific

Written Authorization. Ail Shipping Charges Must Beprepaid.

1-3. PERlODiC CHECKUP 1-5. SERVICE RECOMMENDATIONS This ptlblication includes operatmg and hewice instructions appiving to

,U$ mcchanicd products. such as your Mercury Outboard, require Mercury models listed on the preceding "specifications" &&~n' ihe periodic care a d maintenance. preparation of this book careful consideration was given to such Your outboard should be taken to an authorized Mercury dealer every adjusting and service operations as arc usually required in normd six months or 100 hours of operation - or at least once each year -- for service. Illustrations shown are typical of all specified motors, except lube change, tuneup, etc, to include the following: where model is deuignated.

Page 5

We do not recommend that the owner attempt repain which are not specifically covered in this book Other repairs, particulady those whch require disassembly or replacement of internal parts, should be done only by Authorized Mercury Service facilities. Such facilities would have the necessary factorydesigned tools and equipment, plus the knowledge and experience required to do the job correctly and economically.

1-6. SERIAL NUMBER

The serial number is stamped into the instruction plate on the swivel bracket. The number is the manufacturer's key to numerous engineer- ing details which apply to your motor. When ordering parts, accessories and tools, or when corresponding with the manufacturer or dealer in regard to service matters, always specify model and serial number.

1 I CAUTION: Water pump impeller will be damaged if motor is operated out of water. Read flushing instructions carefully in Paragraph 11 -3, following.

1-7. MOTOR and BOAT INSURANCE Your local insurance agent can offer you motor and boat protection which covers damage, theft, etc, as well as liability for property damage and personal injury to others. Contact your insurance dealer for full details.

1-8. RECORDING ELECTRIC STARTER KEY NUMBER (Electric Starting Models)

I RECORD YOUR I If key is lost, a new key may be( I ELECTRIC STARTER ( purchased from your local ~ e r c u r ~ l

I KEY NO. HERE I dealer. Give key number (left) at time of

purchase. I

Section 2 - Motor Installation

2-1. OUTBOARD MOTOR MOUNTING Your Mercurv Motor is desiened for a recommended transom heirht as

Installation of the motor on the transom should be given very careful shown in re 3. To avo,d damage to transom and to preve&, the motor from working loose duriw operation, it is important that clamp attention. The clamp bracket not only must support the weight of the

motor, but it is subject to thrust, impact, inertia and steering stresses. (thumb) screws are tghtened securely and equally. Thumb screw gr ip

These forces are applieied directly t o the transom thru the clamp bracket should be in (or near) a horizontal plane to allow full tilt up and turn of

assembly. the motor. Failure to obwrve this Ulurnb screw position could result in damage to steering parts.

Page 6

T R A N S O M M O U N T I N G SPECIFICATIONS (Refer to lilustrations on Next Page)

R. Side

R. Side I

Merc Model

* Best transom height for 4 and 6-cylinder engines is to locate engine's anti-cavitation plate parallel and even with the boat bottom. Boats with heavy keels will require lower settings to avoid propeller cavitation. Very fast boats may benefit from higher settings.

Min. B

Min.

A $

** Variable on deep "V" huUs $Includes clearance for Power Trim where applicable. "*" %lows sufficient clearance for Ride-Guide Steering. For rope steering. add to this figure according to type of bracket u s d .

Reeomrnended loation for mounting remote throttle-shift and steering controls on boat to balance e w e t o q u e caused by direction of propeller rotation.

4 2%" for 1971-72 models @15W for 1970-71-72 Merc 40@500 and for Merc 402 Metric Conversion: 1 "= 2.54cm 21%" for 1966 Mere 350 &End of throttle-shift-steering (tiller) handle

Page 7

Min. C*+

Min. D

Min.

F*

short Shaft

Control On Boat MountA H*+* Shaft J

FROM TOP OF TRANSOM TO TOP OF MOTOR WHEN TILTED UP --

FROM TOf ' OF TRANSOM TO

M CLEARANCE

HEIGHT

ADJUST MOTOR TO P O S I T I h AT WHICH GEAR CASE CENTER LINE IS PARALLEL AND EVEN

BEST RESULTS 'WITH NO KEEL IN THIS AREA

WITH BOl7OM OF PLANNING SURFACE

Metric Conversion: 1 "= 25.4mm (millimeters) I '= 0.3m (meter)

CAUTION: Before operating, motors of 20-or-more horsepower must be secured to boat with 2 bolts placed through transom into slots provided at bottom of clamp bracket. Refer to Figure 1 and instructions on red "Caution" tag attached to new motor. Upper mounting bolts must be installed on all Gcylinder motors and on 3 and 4cylinder motors if transom has an extremely hard, smooth surface or for severe service. During operation, clamp screws should be checked occasionally for tightness on the transom. Failure to bolt motor to transom may result in damage to boat and/or loss of motor and possible injury to occupants of boat.

2-2. TILT PIN ADJUSTMENT

Do not operate motor with tilt lock pin removed. Holes are provided in the clamp bracket to permit changing location of tilt lock pin for proper adjustment of tilt angle. Tilt angle of motor on transom should be set so that anti-cavitation plate (Figures 1.3 and 4) is about parallel and even with bottom of boat. Speed of boats, which have center of gravity located forward, may sornetimea be improved by tilting motor out one tilt pin hole. This will tend to raise bow and reduce wetted surface. If motor is tilted in, boat will ride bow down, wetting more of the bottom and reducing speed. The preceding eenerallv. will im~rove owration in rout& water. Under ideal conditidns, efficienj B best kith lower unit operating in level position, ' I INGLf MOlC4 OWNING I

I - ' In up a for maximum becaw entire thrust then 18 applied parallel to plane of motion. With

,need run the hr't test wl th the mo- some boats, however, and under certain unfavorable conditions of I a / 6 I I \

or way i n , clv>e t o the t ransom. move I t v,Lt one p,n hole k:ei loading, there d l be a tendency to ride stern high or bow high. ( F i

C . i ! 1 'Ime i1rit11 ma \ i rnum per fo rmance 1, 3) This condition can be corrected considerably by adjusting a t angie I i---c- \ f so that boat rides level.

/ H31C.8 CENTEll LINE F O 1 WAL MOT04

It must be considered that operation with excessive tilt will reduce I performance noticeably and may induce cavitation. It is, therefore,

preferable to level boat by proper loading rather than by extreme adjustment of tilt angie. Except on very rough water, if tilt angle is correctly adjusted and boat is favorably loaded, a propedy designed boat will ride level and will plane without "spanking" or "bucking."

Figure 3. General Specif iezstiams Transom Mounting (Figure 4) Page 8

2-3. TILT-UP and SHALLOW WATER TROLL LEVER OPER- ATION (Models with Less Than 10 HP)

Motor is spring-locked in operating position and will tilt up only when strilung a submerged object abruptly while in forward motion. To release motors of less than 10 horsepower for tilt pin adjustment, push tilt-up lever, then tilt motor up. (Figure 5) To lock in tilt position for running in shallow water, push lever in direction of ''Release" arrow. To release, return to "Lock" position. Motors of more than 10 horsepower can be tiltedup by placing in "Forward" gear and lifting upout on skeg. (Figure 1)

BOW UP

WRONG! BOW DOWN

RIGHT! PLANE or EVEN KEEL

Model 1972 Merc 110-7540 motors can be placed in shallow wate "Troll" position and released from this position as follows: 1. Retard twist grip throttle to "Shift Range" and shift int~

"Forward"- 2. Push lever in direction of "Troll". 3. Tilt motor manually to enearre in shallow water "Troll" position - -

(Figure 6 ) 4. To release from shallow water "Troll", retard throttle and shift tc

"Forward". Push lever to the side and down. then tilt motor i~ manually by lifting up slowly to disengage' from the "Troll' position.

Figure 4. How to Plane a Boat

Model 1969-70-71 Merc 110-7540 motors can be placed in a shallow water troll position automatically as follows:

greatly increasing wetted surface and reducing boat speed. "Hook" frequently is caused by supporting boat too far ahead

Retard twist grip throttle to "Shift Range". of transom while hauling on a t h e ; br dm& storage. Push lever in direction of "Release" arrow (Figure 5); shift to b. Rocker: The reverne of hook and much l a common "Rocker" reverse. exists if bottom is convex in fore-and-aft direction when viewed Advance throttle in reverse. This will cause motor to tilt up and from below, and boat has strong tendency to porpoise. engage shallow water troll lever (Figure 6 ) automatically. C. Surface Roughness: Mobs, barnacles, etc., on boat or corrosion Retard throttle to "Shift Range" and shift into forward. of motor's gear case increase skin friction and cause speed loss.

Clean surfaces when necessary. Release motor from shallow water troll as follows: 1. To release, return to "Lock" position. (Figure 6) 2. Retard throttle to "Shift Range" and place shift lever in reverse. 3. Advance throttle until shallow water troll lever becomes disengaged. 4. Retard throttle and shift into forward.

24. T i LT STOP LEVER

Motor can be locked in tilt-up position by pulling tilt stop lever (Figure 6) with motor fully tilted.

IMPORTANT: DO NOT use tilt stop lever while trailering. Tilt motor and place a block of wood between clamp and swivel bracket.

-5. CONDITIONS AFFECTING OPERATION Center of Gravity Location: For minimum drag and maximum speed - which allow best fuel economy at a given throttle setting per-mile and perhour of operation - move weight aft until boat porpoises or is about to porpoise. This reduces wetted surface to a minimum, only the rear half of the boat being wet. Boat Bottom: For maximum speed. a boat bottom shodd be nearly a flat plane where it contacts the water and particularly straight and smooth in fore-and-aft direction a. Hook: Exists when bottom is concave in fore-and-aft direction

when viewed from below. When boat is daring, "hook" causes more lift on bottom near transom and allows brow to drop, thus

Page 10

2-6. ADJUSTING CO-PILOT (Models with 20 HP and Leu)

The co-pilot provides velvet-smooth friction control in the steering mechanism. Recommended adjustment is such that the motor will remain in a fixed-course position without the need of manual contrd, yet will not be too tight to allow free and easy steering. Adjustment is attained by means of a hexagon head screw on bottom face of swivel bracket (top face on 1972 Merc 110-7540 models). (Figure 7)Tighten the screw to increase friction; loosen to decrease friction. Loosen friction when using remote controls

Figure 7. Co-Pilot Adjustment

Section 3 - 3-1. PROPELLERS

. - . - -

Propeller Recommendations speed is low, try a lower pitch prop. There normally is a 300-500 RPM

It is not possible to design a single propeller which will give optimum performance under all conditiom of motor speed, boat type and speed and load. The Quicksilver propeller, whlch you have selected. is suitable for most applications. If it does not fit a particular application we suggest that you keep it for general use and acquire another Quicksilver propeller for the particular application.

For propeller recommendations applying to your particular boat, consult your Mercury dealer and see the following paragraph. Using an improper propeller for the application on a new motor wiU void the Warranty Agreement.

3-2. PROPELLER SELECTION

The speed at which a given boat will travel is governed mainly by the horsepower available. Use of the correct propeller will allow the motor to turn at a recommended RPM and develop full power. First select trial propcller from dealer's listing, using approximate boat length and load, if known. This usually will be the correct choice. Refer to transom height recommendation in chart in Figure 3. Establish exact tilt pin setting by test.

To check, make a trial run, using an accurate tachometer. It is important that the motor speed (RPM) falls within the recommend~d limits. The trial run should be made with a light load (one person). Under these conditions, it is desireable to have the engine speed near thc top of the rccomrnended limit so that, under a heavy load, motor speed will not tall below recommendations. If the motor speed is too hlgh, t ry a higher pitch or the same pitch cupped. Likewise, if motor

charge between propeller pitches.

For dual installation, the next lugher pitch propeller may be best. For water skiing, it may be desireable to use the next lower pitch propeller, however, be cautious - do not operate at full throttle when using ski propeller but not pulling skiers. If, in this connection, a propeller has too little pitch for the application, dangerous overspeed of the motor may result! If a propeller has too much pitch for the application, acceleration wdl be slow.

Light, fast boats require hlgher pitch propellers, while heavier boats require lower pitch propellers. Use aluminum propellers in salt water areas to reduce electrolytic action which can result in corrosion and pitting of metal surfaces.

3-3. INSTALLING PROPELLER Apply a liberal coat of Perfect Seal (C-92-34227) or a waterproof-ty pe lubricant on splines of propeller shaft, especially if operated in salt water, to aid in removing at any future time.

FOLLOW THESE STEPS: I

WARNING: When installing or removing propeller, because of the motor's ease in starting, (be sure that switch is off on electric starting models), place a block of wood between anticavitation plate and propeller to prevent accidental starting and to protect hands from propeller biades while removing the propeller nut.

Page 11