Snow Hawk 600HO Set-up, Service And Shop Manual

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MY2004

Set-up, Service

and Shop Manual

SNOW HAWK 600HO

FOREWORD

Congratulations, and thank you for buying an A.D. Boivin design inc. Snow Hawk™ vehicle. We

appreciate the confidence in our product that you have demonstrated by making this purchase

Several years of design, tests and improvements were necessary to produce this vehicle which combines performance, driving pleasure and safety.

Proper maintenance on a regularly-scheduled basis is essential in order to obtain the performance you have the right to expect from your machine. In this manual, you will find all the information needed for adjustments to and the maintenance of this vehicle.

We sincerely hope that you will have many years of enjoyment with your Snow Hawk™.

AD Boivin design Inc.

All the information, illustrations, photographs and specifications found in this manual are based on the latest available data at the time of publication. Due to improvements or other changes, it is possible that you will note a few differences. AD Boivin design Inc. reserves the right to make changes at any time.

WARNING /CAUTION / NOTICE

●

NOTICE:

The information in the NOTICES is designed to explain maintenance procedures and to ensure the best possible use of the vehicle.

IMPORTANT REMARKS

Using this vehicle can be a very pleasurable experience and we wish you all the enjoyment that it can bring you. However, if certain rules are not respected, this sport can become a source of environmental problems and of interpersonal conflicts.

Adopting a responsible attitude and behaving in a responsible manner at all times will help avoid such problems and conflicts.

PROTECT THE FUTURE OF YOUR SPORT. BE RESPONSIBLE AND RESPECT LOCAL LAWS AT ALL TIMES. DEMONSTRATE AN AWARENESS OF THE IMPORTANCE OF THE ENVIRONMENT AND RESPECT THE RIGHTS OF OTHERS.

WARRANTY

1. All the parts of this vehicle are covered by the warranty for a period of one winter season against any problem related to its assembly or construction.

Please read this manual and follow the instructions carefully. Pay particular attention to the boxes entitled WARNING and CAUTION as well as to the paragraphs preceded by the word NOTICE.

◆ WARNING

This symbol is designed to call attention to particular instructions and procedures, which, if not followed to the letter, could cause injury and even fatal accidents.

▼ CAUTION

This symbol is designed to call attention to particular instructions and procedures, which, if not followed to the letter, could cause damage to or even destruction of the vehicle.

2. The labour costs of repairs covered by the warranty are the responsibility of the vehicle owner.

3. The company reserves the right to require that the dealer carrying out the repairs send back any parts declared or suspected to be defective.

LOCATION OF THE V.I.N.

IMPORTANT MAINTENANCE WARNINGS:

◆ WARNING

Never have the motor running inside a building. The exhaust fumes contain carbon monoxide, a colourless, odourless gas which can cause death or severe injuries.

Allow the motor to run only in a well-ventilated area.

◆ WARNING

When hot, a motor, an exhaust system or a drive system can cause burns.

Wait until they have cooled before carrying out maintenance.

◆ WARNING

The gas tank can catch fire if it is not handled correctly. Gas vapours can burst into flames easily.

◆ WARNING

Carrying out maintenance of this vehicle while the motor is running can be dangerous. Injuries could result from contact with moving parts.

Make sure you turn off the motor before working on the vehicle.

◆ WARNING

Working on this vehicle without wearing the appropriate clothing can be dangerous. Injuries could result if you are not adequately protected.

Always wear the necessary equipment when working on the vehicle: shoes, goggles, gloves and/or mask if necessary.

Important information concerning maintenance

o Replace any joints, brake shoes, pins and clips

by new ones.

Do not smoke while carrying out vehicle maintenance.

Do not carry out maintenance anywhere near exposed flames or sparks.

◆ WARNING

Brake fluid can be dangerous for people and animals. These fluids are harmful or fatal if swallowed and must not come into contact with the skin or eyes.

o Use special tools when so indicated.

o Use original parts as well as recommended

products.

o After reassembling the vehicle, inspect the parts

and verify the torque on the nuts and bolts.

Replacement parts

Use only A D Boivin parts or their equivalent. A D Boivin’s original high-quality parts are designed and

manufactured especially for your vehicle.

●

NOTICE:

Using replacement parts that are not equivalent or are of inferior quality could mean your vehicle will not be able to perform as it should and could damage your machine.

MANDATORY SERVICE PRODUCTS

Loctite RC/609, 10 ml

Retaining compound

P/N 413 703 100

Loctite 271, 10 ml

High strength

threadlocker

P/N 293 800 005

Loctite 243, 10 ml

Medium-strength

threadlocker

P/N 293 800 015

Sealing compound, 30 ml

P/N 420 297 905

Loctite Primer, 128g

P/N 413 708 100

Loctite 515, 50 ml

Paste gasket

P/N 413 702 700

MANDATORY SERVICE PRODUCTS (continued)

Loctite chisel, 510g

Gasket/paint remover

P/N 420 899 763

Molykote G-n plus. 50g

P/N 711 297 433

Molykote PG 54, 10g

P/N 420 899 763

Isoflex Grease, 50g

P/N 293 550 021

Petamo Grease

P/N 420 899 271

Loctite 518, 50 ml

Gasket Paste

P/N 293 800 038

RECOMMENDED SERVICE PRODUCTS

Bombardier injection oil

3 x 4 litres P/N 413 803 000

Pre-mix oil

12 x 500ml P/N 413 803 100

Premixed coolant 50/50

16 x 1 litre P/N 293 600 038

Synthetic injection oil

Bombardier Formula XP-S II

3 x 4 litres P/N 293 600 046

Synthetic injection oil Bombardier Formula XP-S II 12 x 1 litre P/N 293 600 045

Fuel stabilizer

12 x 8 oz P/N 413 408 600

RECOMMENDED SERVICE PRODUCTS (continued)

Storage oil 12 x 350 g Canada P/N 413 711 600 USA P/N 413 711 900

Synthetic Grease 400 g

P/N 413 711 500

LMZ Grease No 1, 400 g

P/N 413 707 500

Molykote 111, 50 g

P/N 413 707 000

Bombardier lube

12 x 14 oz P/N 293 600 016

Silicone dielectric grease, 3 oz

P/N 293 550 004

RECOMMENDED SERVICE PRODUCTS (continued)

Anti-seize compound, 236 ml

P/N 293 800 070

Pulley flange cleaner, 320 g

P/N 413 711 809

Brake fluid SRF ( DOT 4 )

P/N 293 600 063

Heavy Duty Cleaner

400 g P/N 293 110 001

4 litres P/N 293 110 002

Brake fluid GTLMA (DOT 4)

P/N 293 600 062

Shock oil 32 oz

P/N 293 600 035

RECOMMENDED SERVICE PRODUCTS (continued)

Loctite 592, 50 ml

Pipe sealant

P/N 293 800 018

Loctite 648, 5 ml

High temperature and strength

retaining compound

P/N 413 711 400

Plastic and vinyl cleaner

P/N 413 711 200

Loctite Ultra Copper, 80 ml

High temperature RTV sealant

P/N 293 800 090

Loctite 5150, 300ml

P/N 293 800 066

TABLE OF CONTENTS

GENERAL INSTRUCTIONS

PERIODIC MAINTENANCE

FUEL SYSTEM

ENGINE REMOVAL

REWIND STARTER

COOLING SYSTEM

ENGINE (CYLINDERS / HEAD / BASE)

PRIMARY TRANSMISSION SYSTEM

SECONDARY TRANSMISSION SYSTEM

HYDRAULIC BRAKE SYSTEM

FRONT FORK AND TWIN-AXIS SKI

REAR SUSPENSION, SHOCKS AND TRACK

CHASSIS AND STEERING

ELECTRICAL SYSTEM

DIMENSIONS AND TOLERANCES

WIRE, CABLE AND HOSE ROUTING

FIRST CONTACT

The SNOW HAWK™ is a completely new type of vehicle. Technically speaking, it is a cross between a snowmobile and a motorcycle. However, its behaviour depends on the conditions in which it is used. Sometimes, it will react more like a bike while at other times, it will react more like a snowmobile or a jetski.

Describing exactly how the SNOW HAWK™ behaves is difficult. This is why we recommend that you take the time to become acquainted with your machine in an area free of any obstacle. This first contact should take place at low speed, with a series of basic manoeuvres that will allow you to learn about the reactions of the vehicle.

A good exercise is to follow a "figure 8" trajectory because this will allow you to experiment with right- and left-hand turns followed by accelerating and braking.

Turning can be done by steering right or left, keeping in mind the speed of the vehicle, the snow conditions and how quickly you want to change direction.

GENERAL INSTRUCTIONS 1 - 1

◆ WARNING

Some people enter a turn by stretching out a leg on the inside of the turn and letting the foot slide over the ground (a technique used in motocross). We advise against this practice which could cause severe injuries if your foot should sink into the snow. We rather suggest keeping both feet on the footpegs as much as possible.

An upright position, with the knees clutching the gas tank and the elbows pointing away from the vehicle, will give a sense of security and provide greater freedom of movement while accelerating or slowing down.

◆ WARNING

The greatest danger in using this vehicle is the perception you may have of how competent you are. Overestimating how competent you are can result in hazardous situations both for yourself and for other trail users.

Do not forget to take all the time that is necessary for you to practice and feel comfortable at low speeds before attempting high-speed manoeuvres. You will then be able to fully appreciate the joy of driving.

GENERAL INSTRUCTIONS 1 - 2

LOCATION OF MECHANISMS AND CONTROLS (503 SHOWN, 600HO IDENTICAL)

1. Throttle control

2. Brake lever

3. Parking brake lever

4. Engine-cutoff (tether)

5. Gas tank cap

6. Dimmer switch

7. Choke control

8. Emergency-stop button

9. Temperature Light

10. Hood latches (4)

11. Rear module latches (4)

12. Bellypan latches (6)

13. Kick stand

14. Headlight

15. Stop and tail light

16. Recoil starter handle

17. Hood latches (4)

18. Rear module latches (4)

19. Bellypan latches (6)

FUEL

(

)

(

)

This vehicle is powered by a two-stroke engine that uses a premixed gasoline and oil mixture.

Gasoline: Regular unleaded gas with a minimum octane

rating of 89 (R+M)/2

GENERAL INSTRUCTIONS 1 - 3

Motor oil: Bombardier / ROTAX Formula XPS Synthetic

Pre-mix oil (P/N 293600045)

Mixture ratio: 40 : 1 (32 : 1 for break in and CAN safely be

used thereafter if desired)

Fuel tank capacity: 30 L (9.5 gallons)

▼ CAUTION

A mixture in which the proportion of oil is too low will cause piston failure. On the other hand, a mixture in which the proportion of oil is too high will cause excessive carbon deposits that will result in fouled spark plugs and will affect performance.

Always mix in a proportion of 40 parts of gasoline for each part of oil.

●

NOTICE:

o The use of isop[ropyl alcohol (commonly known as “gas-

line antifreeze) is recommended in a ratio of 150 mL per fuel tank in very cold temperatures.

Gasoline

Oil

5125 10 250 15 375 20 500 25 625

30 75

o Avoid mixing oils of different brands.

GENERAL INSTRUCTIONS 1 - 4

OPERATING INSTRUCTIONS

Pre-driving inspection

◆ WARNING

A pre-driving inspection is of the utmost importance before using the vehicle. Do not start the machine until you are sure all mechanisms and controls are functioning properly. Failing to proceed in the prescribed manner may result in severe injuries or even death.

o Make sure the track and the idler wheels are not frozen and

that they move freely.

o Depress the brake lever and make sure the brake is fully

engaged before the end of the lever touches the handlebar. The lever must return to its original position as soon as it is released.

o Turn the twist throttle control a few times to make sure it

functions properly. The control must return automatically to the idle position as soon as it is released.

o Make sure the engine cutoff switch, the stop light, the

headlight (high and low beams) and the tail light are in good working order.

Starting the engine

o Put the cap of the engine cutoff (tether) switch in place. The

other end of the cord must be securely attached to the driver.

o If the engine is cold, use the choke control.

0. Normal position (not activated)

1. Intermediate choke position

2. Full choke position

o Start the engine by firmly pulling the handle of the rewind

starter.

◆ WARNING

Do not touch the throttle control while starting the engine.

Stopping the engine

o While the engine is idling, remove the engine cutoff cap

(tether) or press the emergency-stop button.

BREAK-IN PERIOD

Engine

▼ CAUTION

A cautious break-in period of 10 to 15 hours is essential before using the vehicle at full power. Failure to provide a sufficient break-in period could result in severe engine damage.

▼ CAUTION

The timing of all Snow Hawk 600HO’s is retarded by 3o for a period of 1-hour during the first stages of the break-in period. You may notice a slight increase in performance and a reduction in fuel consumption after this time.

GENERAL INSTRUCTIONS 1 - 5

During the break-in period, the throttle control should not be turned more than ¾ of its range. However, occasional periods of brief, brisk acceleration and frequent speed variations contribute to a good break-in. On the other hand, periods of long, high acceleration, sustained high speed and engine overheating are harmful during the break-in period.

◆ WARNING

This vehicle is equipped with a liquid cooling system. ALWAYS ride with the rear deflector pad installed and in conditions where there is enough snow to properly cool the engine. If the red temperature light on the steering column should ever illuminate, stop immediately and let the vehicle cool down, and then find some snow. NEVER continue to operate the vehicle with the temperature light illuminated as severe engine damage will occur.

▼ CAUTION

A fuel : oil mixture of 32 : 1 MUST be used during the engine break-in period.

◆ WARNING

During the first hour of the break-in period the fluid levels in the coolant reservoir and the small water pump oil reservoir will go down slightly. This is perfectly normal. Be sure to top-up these fluids with proper coolant (P/N

293600038) and proper oil (P/N 293600045).

GENERAL INSTRUCTIONS 1 - 6

Drive Belt

A new drive belt must be submitted to a 5-hour break-in period. Avoid high-speed driving and brisk accelerations during this period.

Inspection – 10 hours

A general inspection is recommended after the first 10 hours of use. This inspection must be carried out by an authorized SNOW HAWK ™ dealer.

●

NOTICE:

o Most of the wear in this vehicle occurs during the break-in

period.

o Bolts and nuts can easily become loose in a new machine.

Make sure you check them regularly during this period.

REMOVAL OF THE BODY PANELS (HOOD, REAR MODULE AND BELLYPAN)

In order to work on the vehicle more easily and to access the anchor ties, we suggest that you remove the rear module from the vehicle. To do so, you must first remove the hood. Proceed as follows:

o Disconnect the front headlight.

o Unhook the 4 rubber latches (2 / side).

o Remove the hood.

o Remove the fuel tank cap.

o Set the choke to the full position.

o Unplug the tail light connector located under the light

itself, underneath the rear fender.

o Release the rear module from its four rubber latches,

slip the rewind starter handle through the space provided and remove the rear module.

Roll the two O-rings down and pull the two white plastic collars down over the fork legs. To ensure that they will not interfere, let them hang loose at the base of the fork leg.

o Remove the circular fork disc

o De-latch the two rubber latches on the sides of the belly

pan (towards the rear of the vehicle)

o De-latch the four rubber latches on the bottom of the

belly pan.

o Descend the belly pan to floor level; most maintenance

can be performed with the belly pan in this position. However, if it is required to completely remove the belly pan, remove the single bolt attaching the ski to the fork. At this point, a second person can lift the front of the vehicle slightly and the belly pan can be slid out from underneath.

GENERAL INSTRUCTIONS 1 - 7

PERIODIC MAINTENANCE 2 - 1

V-V

(

)

V-V

)

V-V

g g

●

NOTICE:

Regular inspection and maintenance of the Snow Hawk is of utmost importance. Follow the guidelines in the table below for optimum vehicle performance. Suggested intervals must be reduced if the vehicle is subjected to severe usage conditions.

65 Hrs

(yearly)

- A

- F

- R

- C

- R

- A

- A - R

- A

Item

2.1 Carburetion

2.2 Motor

2.3 Primary transmission system

2.4 Secondary

transmission system

2.5 Brake system

2.6 Front suspension and ski

2.7 Rear suspension and track

2.8 Chassis

2.9 Electrical system

Interval (Hrs)

Fuel lines and connections Carburetor adjustment Throttle cable Air Intake Filter Carburetor support bracket Starter cord Cylinder head bolts Engine support bolts Exhaust system Coolant level Oil level Cooling System (hose connections) Primar Primar Primar Secondary clutch pre-tension Secondar Cog sprockets Torque Limiter Taper Locks Brake fluid Brake pads Brake microswitch Front Fork Fork rubber cushion and bolt Fork air bleeder screw Twin axis ski bushin Ski and runners Suspension Shocks Track Handlebar bolts Steering components Assembly bolts / nuts Spark plu Spark plu Fuse Headlight projection/aim Lighting system, stop lamp and emergency stop switch

water pump oil reservoir

drive belt and secondary clutch clutch bolt

drive belt (cog belt

s / nuts

Break-in

( ~ 10 Hrs. )

- A - -

---V

- A -

- A V--V

V - A - - V - A

V--V

V--V F-FF

- A

- A VV - R

V - A - V - A V - A

V--V - C

- A - R -

- A - -

---

VV-V

5 Hrs

--V - C

--V - A

--F

- A

V - R as needed

15 Hrs

- R

- A

- A - R

●

NOTICE:

V = Verify, A = Adjust, C = Clean, R = Replace one or several part(s), F = Replace fluid

PERIODIC MAINTENANCE 2 - 2

2.1. CARBURETION

Fuel lines and connections

Check all hoses and connections in order to find and fix leaks and/or to help prevent them.

Carburetor adjustment

For carburetor adjustment, refer to Chapter 3 - Fuel system section.

Throttle cable

The throttle cable can be adjusted by setting the adjustment mechanism on the throttle end of the throttle cable.

Air intake filter

The air intake filter must be cleaned at least once a year, or more often under severe usage conditions. Clean the filter in a solution containing a non-flammable cleaning solvant (such as hot soapy water). Once dry, apply some light engine to the filters to prevent the infiltration of water and dust.

2.2. ENGINE

Recoil starter cord

Pull gently on the handle to unwind the full length of the cable. Inspect the cable visually to detect any wear or other damage that could eventually cause the cord to break.

Cylinder head bolts

Refer to the appropriate procedure in Chapter 7 – Engine (Cylinders/Head/Base).

Engine support bolts

To carry out this operation, refer to the appropriate procedure in

Chapter 7 – Engine (Cylinders/Head/Base).

Exhaust system

Using a torque wrench, check the torque of the retaining bolts of the exhaust manifold. Apply a torque of 10 N-m (1 kg-m, 7.4 lbf- ft).

Then, proceed to a visual inspection of the system to detect any leak or abnormality in the gasket material.

PERIODIC MAINTENANCE 2 - 3

Cooling system

Inspect the coolant level in the coolant reservoir located on the MAG side of the vehicle. If the coolant level is below the “Cold” coolant mark when the vehicle is not warm or has not been ridden within 30mins or more, add coolant until this line. Check all of the hoses / hose connections and ensure that there are no fluid leaks in the system.

Cold Level

PERIODIC MAINTENANCE 2 - 4

2.3. PRIMARY TRANSMISSION

Primary and secondary clutches

Remove the belt and verify that the sliding half-pulleys of the two clutches is in good working condition.

To take the belt off, first use the special tool provided to open the secondary clutch (P/N 529 008 700). Then, slip the belt over the pulley from rear to front as illustrated. To reinstall the belt, proceed in the reverse order.

Primary clutch bolt

Check the torque on the primary clutch retaining bolt.

Recommended torque: 90 - 100 N-m (9–10 kg-m, 70 lbf-ft).

For more information, refer to Chapter 8 - Primary Transmission System.

Pre-tension of the secondary clutch spring

For more information, refer to Chapter 8 - Primary Transmission System.

Primary transmission belt

Examine the belt. Make sure it is not cracked, frayed or worn in an abnormal way (uneven wear, wear on one side only, missing cogs, or cracked material). Abnormal wear of the belt is often due to mis-alignment of the pulleys, excessive throttle when the track is frozen, quick acceleration without a preliminary warmup, a scratched or rusted pulley, oil on the belt, or a twisted replacement belt. If need be, ask an authorized SNOW HAWK™ dealer for advice.

Measure the width of the belt. Replace if it is less than 31.6 mm (1.245 in) wide.

For more information, refer to Chapter 8 - Primary Transmission System.

2.4. SECONDARY TRANSMISSION

Secondary transmission cog belt

Examine the cog belt. Make sure it is not cracked, frayed or worn in an abnormal way. If in doubt as to the condition of the belt, replace it with a new one.

Verify the tension of the secondary transmission belt according to the instructions found in Chapter 9 - Secondary

Transmission System.

PERIODIC MAINTENANCE 2 - 5

Cog Sprockets

Check the appearance of the cog sprockets. Make sure all the sprockets are there and are free of any accumulated dirt. Clean if necessary.

Taper-locks

Refer to Chapter 9 - Secondary Transmission System.

2.5. BRAKE SYSTEM

Brake fluid

Check to see if the brake fluid level is above the "mimimum" mark (see illustration). If not, add fluid.

▼ CAUTION

MIN

Use only DOT 4 brake fluid from a sealed container. Do not use any other type of brake fluid.

PERIODIC MAINTENANCE 2 - 6

Brake pads

Verify the thickness of the brake pad linings as illustrated. Brake pads must both be replaced if either one of them shows a clearance of less than 1 mm (1/32 in.).

●

NOTICE:

For the replacement of brake fluid, refer to Chapter 10 –

Hydraulic Brake System.

2.6. FRONT SUSPENSION AND SKI

Front fork

The air pressure inside the fork legs must be as close as possible to atmospheric pressure. Therefore, it is advisable to remove the bleeder screws after every ride to re-establish the pressure. It should be done more frequently when temperature variations are greater and more frequent (such as when the vehicle is stored in a heated garage).

A visual inspection of the fork legs can reveal oil leaks that might indicate broken main seals. If excessive oil is presest on the lower fork leg, a seal replacement may be required.

It is recommended to replace the fork oil after the break-in period and, from then on, after every 15 hours of use. For details, refer to Chapter 11 – Front Fork and Twin-Axis Ski.

▼ CAUTION

It is advisable to change the fork fluid when preparing the vehicle for storage. The presence of condensation in the suspension fluid could cause corrosion during the storage period.

Twin-Axis Ski and Runners

Verify the torque of all the bolts holding the ski, as well as all the studs and nuts retaining the runners. Also inspect the appearance of the runners to detect any wear, distortion, or broken studs.

2.7. REAR SUSPENSION AND TRACK

Suspension

Verify that all suspension bolts and nuts are well tightened, especially the four that retain the suspension to the chassis (use Loctite 243 here) Verify that none of the parts are damaged or missing.

Verify that the suspension wheel bearings are in good working order. Check the condition of the suspension limiter straps. Check the condition of the hyfax.

For more information, refer to Chapter 12 - Rear suspension

and Track.

Shock absorbers

Check around the shock guards for the presence of oil leaks.

PERIODIC MAINTENANCE 2 - 7

Shock oil must be replaced once a year. Refer to Chapter 12 Rear suspension and Track.

▼ CAUTION

It is advisable to change the shock fluid when preparing the vehicle for storage. The presence of condensation in the suspension fluid could cause corrosion during the storage period.

Track

Check the condition, alignment and tension of the track.

With the engine turned off and the rear end of the machine raised from the ground, rotate the track manually and inspect it to make sure it is in good working condition. It must not be cracked and all the lugs must be intact.

●

NOTICE:

For track alignment and tension, refer to Chapter 12 - Rear Suspension, Shocks and Track.

PERIODIC MAINTENANCE 2 - 8

2.8. CHASSIS AND STEERING

Handlebar mounting bolts

Verify and adjust the torque to 36.5 N-m (3.7 kg-m, 27 lbf-ft), following a criss-cross order.

Steering mechanism

Verify the condition of the tie rod ends and check for excessive play in the pivots of the steering system. For alignment, refer to

Chapter 13 – Chassis and Steering.

PERIODIC MAINTENANCE 2 - 9

Assembly

The chassis of the SNOW HAWK is different in that most of the assembly is done by bolting components rather than welding them. Therefore, bolts must be checked and tightened as need be. When doing this, refer to the Torque Table at the end of this section.

2.9. ELECTRICAL SYSTEM

Spark plug

Check the general condition of the plug, the colour of its electrodes, carbon deposits, plug gap and possible damage to the gasket

A NGK BR9ECS spark plug is recommended.

Check the spark plug gap. The suggested gap is 0.45 mm (0.018").

When tightening the spark plug, the torque must be between 25 and 30 N-m (18 and 21.5 lbf-ft; 2.5 and 3.0 kg-m).

Lean

(light grey)

Normal

(brownish)

Rich

(black)

PERIODIC MAINTENANCE 2 - 10

Porcelain Colour Probable Cause

- Plug Temperature rating is too high

Light Grey (Overheated)

Blackish (Fouled)

- Plug gap too wide

- Air/Fuel mixture too lean

- Stale gasoline

- Plug temperature rating too low

- Plug gap is too small

- Air/Fuel mixture too rich

- Oil/Fuel mixture too rich

▼ CAUTION

The engine may be seriously damaged if the temperature rating of the spark plug is inadequate.

Refer to the NGK codification on the next page.

Symbols used on the NGK spark plugs

PERIODIC MAINTENANCE 2 - 11

PERIODIC MAINTENANCE 2 - 12

(6)

)

(4)

Spark plug gap

The suggested gap is 0.45 mm (0.018"). For more information, refer to Chapter 14 – Electrical System.

Wiring Harness

Electrical wires and connections should be inspected visually to quickly locate broken wires or faulty connections. For more information, refer to Chapter 14 – Electrical System.

Headlamp, stop lamp and engine cut-off switch

Before each ride or excursion, it is recommended to verify that the headlamp, the stop/tail lamp and the engine cut-off switch are in good working order.

TORQUE TABLE

ITEM N-m kg-m lbf-ft lbf-in

Torque Limiter bolts Rear Suspension mountin Rear Suspension lower swin Recoil starter housin Primar Secondar Taper-Lock installation setscrews Spark plu Handlebar mountin Triple clamp bolts Fork pivot bolts Ski runner nuts Lower clamp nuts Ski saddle/fork adaptor nut

clutch bolt

bolts

bolts (4

arm bolts (2

bolt

6.20.624.6 55 51 5.1 38 450 90 9 66 792

70.75 62

90 9 66 792

31.7 3.17 23 276 14 1.4 10.4 125 25 2.5 18 216

36.5 3.65 27 324

6.8 0.68 5 60 45 4.5 33 396 19 1.9 14 168 23 2.3 17 204 85 8.5 63 756

For any other bolt or screw that is not mentioned in the list, please refer to the following table.

BOLT

DIAMETER

(MM)

6 101 784151.511132

8 25 2.5 18 216 36 3.6 27 324 10 49 4.9 36 432 72 7.2 53 636 12 85 8.5 63 756 125 12.5 92 1104

N-m kg-m lbf-ft lbf-in N-m kg-m lbf-ft lbf-in

GRADE " 8.8 "

GRADE " 10.9 "

FUEL SYSTEM

FUEL SYSTEM 3 - 1

24 25

FUEL SYSTEM 3 - 2

1 ADB-SH1 1 Fuel tank 31L

2 322111-BKL 1 Gas tank cap 3 907301 1 7/32" gas tank (overflow)

4 SH15 1 Rubber Strap 15" 5ADB-01401Air box

6 508,000,240 1 Intake horn

7 508,000,199 1 Foam 8 508,000,132 2 Intake adaptor

9 508,000,346 2 Gear clamp

10 415,128,729 1 TM40 Carburetors (racked together, as a pair) 11 512,059,835 2 Gear clamp

12 07-0401 1 Throttle cable 13 512,059,110 1 Choke cable 14 512,059,094 1 Plastic nut

15 394,103,300 1 Lock washer (interior tooth) 16 01-0054 1 Twist throttle 17 24-1101 1 Grips (pair) 18 403,901,811 1 Fuel pump 19 414,420,700 3 Spring clamp (green) 20 14-349 1 Tubing 21 415 080 200-1 1 Hose (pump - carburetor) 22 414,415,200 2 Spring clamp (red) 23 415,079,800 1 Impulse hose 24 513,032,979 2 Spring clamp (dark green) 25 513,033,022 1 Hose 26 420,874,370 1 Male connector 27 07-241 1 Fuel filter 28 570,135,100 1 Grommet 29 415 080 200-4 1 Hose (connector - tank) 30 SH 092 1 Short spacer 31 SH 091 1 Long spacer 32 170-103 2 " T " Nut 33 SN328-016 1 Hexagon flange head cap screw ¼-20 x 1 ¼

Fuel System

Part DescriptionsRef. P/N Qty

34 SN328-014 1 Hexagon flange head cap screw ¼-20 x ¾ 35 8461k133-1 2 Adhesive rubber pad 1/8" thick x 2" wide

CARBURET0RS (TM 40)

FUEL SYSTEM 3 - 3

FUEL SYSTEM 3 - 4

Carburetors (TM 40)

1 403,138,740 1 TM40 Carburetors (racked together, as a pair)

2 404,162,017 1 Funnel (PTO)

3 404,161,955 2 Screw

4 404,161,945 2 O-ring

5 404,106,200 2 Main jet 380

6 404,161,944 2 Pilot jet 17.5

7 404,162,016 2 Needle 9DHI12-58-3

8 404,162,020 2 Piston Valve 2.0

9 404,137,600 2 Packing

10 404,152,200 2 E-ring

11 404,161,940 2 Gasket

12 404,161,939 2 Cover

13 404,162,006 1 Throttle shaft 14 -XXX- 1 Screw

15 -XXX- 1 Adjustment spring 16 404,161,935 2 O-ring 17 404,161,961 2 O-ring 18 404,161,933 4 Screw 19 404,161,932 2 Float 20 404,161,960 2 Float Body 21 707,200,027 1 E-ring 22 404,162,007 4 Plate 23 404,162,008 2 Holder 24 404,161,928 2 Screw 25 404,162,009 2 Lever 26 404,161,926 2 Ring 27 404,161,925 1 Ring 28 404,161,924 2 Ring 29 404,161,923 4 Screw 30 404,138,300 2 E-ring 31 404,162,010 2 Spring 32 404,162,011 1 Spring 33 404,161,920 2 Screw 34 404,161,919 2 Plate 35 404,162,012 1 Funnel (MAG) 36 404,161,918 1 Spring (PTO) 37 404,161,917 1 Screw (PTO) 38 404,162,022 1 Bracket (PTO) 39 404,162,014 1 Spring 40 404,162,015 1 Throttle shaft 41 404,137,500 1 Adjustment screw 42 404,161,913 1 Spring

Part DescriptionsRef. P/N Qty

FUEL SYSTEM 3 - 5

Ref. P/N Qty Part Descriptions

43 404,161,912 1 Screw 44 404,136,100 1 Screw

Carburetors (TM 40)

45 404,161,911 2 Screw 46 404,161,910 3 Screw 47 404,161,909 2 Lever 48 404,140,000 2 Cap 49 404,136,900 2 Holder guide 50 404,161,908 2 Spring 51 404,161,907 2 Plunger ass'y 52 404,161,906 2 Screw 53 404,161,905 1 Nipple 54 404,162,001 2 Hose 55 404,161,903 2 Screw 56 404,162,000 1 Bracket 57 404,161,901 1 Starter lever 58 404,161,899 2 Cap 59 404,161,898 2 Adjuster 60 404,161,897 2 Spring 61 404,161,896 2 Washer 62 404,161,895 2 Packing 63 404,153,400 2 Nipple 64 404,154,900 2 Cap 65 404,161,894 3 Packing 66 404,103,500 1 Spring 67 404,161,981 1 Shaft ass'y 68 404,161,956 1 Hose 69 404,161,957 2 Clip 70 404,138,800 8 Screw 71 -XXX- 1 Spring 72 270,500,118 2 Packing 73 270,500,095 2 Closure cap

FUEL SYSTEM 3 - 6

REMOVAL

Loosen clamps # 9 retaining air box # 5 to carburetor assembly and remove air box.

Disconnect the carburetor support block that is located at the middle-bottom of the carburetor assembly. Pull rearwards on the upper portion of the block to disconnect it completely.

Loosen clamps # 11 retaining dual carburetor assembly to carburetor sockets.

Disconnect throttle and choke cables.

▼ CAUTION

Always loosen the LOWER nut when removing the throttle or choke cable as to avoid disturbing the settings of either.

Remove dual carburetor assembly, pinch and disconnect fuel line. Take care to recuperate fuel.

Clamp

Carburetor support

◆ WARNING

Fuel is flammable and explosive under certain conditions. Always wipe off any fuel or oil spillage from the vehicle. Ensure work area is ventilated. Do not smoke or allow open flames or sparks in the vicinity.

CLEANING AND INSPECTION

The entire carburetor should be cleaned with an all-purpose cleaner and dried with compressed air before disassembly.

▼ CAUTION

Heavy duty carburetor cleaner may be harmful to the float material and to the rubber parts, O-ring, seats, etc. Therefore, it is recommended to remove those parts prior to cleaning.

Fuel line

Lower nut

▼ CAUTION

Carburetor body and jets should be cleaned with carburetor cleaner following manufacturer’s instructions. When jets are very dirty or coated with varnish and gum, replace them.

◆ WARNING

Solvents with a low flash point such as gasoline, naphtha, benzol, etc., should not be used as they are flammable and explosive.

Inspect the condition of the tip of the fuel inlet valve. If the tip is worn, replace both the valve and its seat.

FUEL SYSTEM 3 - 7

●

NOTICE:

Install only a snowmobile carburetor inlet valve as it is designed to function with a fuel pump.

Check to see if the throttle slide is worn and replace it if required.

Check for fuel that may have soaked into float # 8; replace as necessary.

Check float for cracks or other damage affecting free movement; replace as necessary.

Inspect throttle and choke cables and housings for any damage. Replace as necessary.

FUEL SYSTEM 3 - 8

DISASSEMBLY AND RE-ASSEMBLY

●

NOTICE:

To ease the carburetor disassembly and assembly procedure, it is recommended to use carburetor tool kit (P/N 404 112 000)

# 20 FLOAT BOWL

Unscrew drain screw # 3 and screw # 52. Remove float bowl.

# 19 FLOAT AND NEEDLE VALVE ASS’Y

Unfasten both screws # 18 then, pull out float and needle valve assembly # 19.

Upon re-assembly, apply Loctite 243 on screw threads.

# 5 MAIN JET

The main jet installed in the carburetor has been selected for a temperature of - 20°C (0°F) at sea level. Different jetting can be installed to suit temperature and/or altitude changes. A service bulletin will give information about calibration according to altitude and temperature.

Main jet # 5 may be removed without removing float bowl # 20 by first removing drain screw # 3.

# 6 PILOT JET

Use narrow screwdriver from carburetor tool kit (P/N 404 112

000) to unfasten pilot jet # 6.

◆ WARNING

It is critical to the free operation of the throttle slide that the 2 connecting plates as assembled in one carburetor be of the exact same length. Always replace the connecting plates by a pair of new ones that were matched at the factory for length and discard the old ones. Simultaneously replace all the plates of the carburetors of a same rack.

●

NOTICE:

Do not disassemble throttle slide needlessly.

▼ CAUTION

After throttle slide reassembly, proceed with a leak test. See below for procedure.

# 7 NEEDLE

FUEL SYSTEM 3 - 9

Remove carburetor cover

Loosen needle retainer screw # 33.

# 12.

Fully open throttle and hold in this position for the following step.

Move aside needle retainer # 34.

1. Needle retainer moved aside.

Turn dual carburetor assembly upside down to free needle # 7. Take care not to loose plastic washer # 9 under needle circlip #

10.

# 2 INTAKE SPICKET

Unscrew throttle slide cover screws # 70.

Open throttle 3/4 wide and hold it there.

Lift throttle slide covers bottom first until they are free from carburetor bodies. Then, slide them out.

1. Lift bottom first

2. Slide out

After inserting throttle slide cover in place and be-fore installing screws, ensure O-ring gasket is properly seated in its groove especially in the area around vent nipple. See illustration at right.

1. Needle retainer

2. Ensure O-ring gasket is properly seated in nipple area.

FUEL SYSTEM 3 - 10

CARBURETOR ADJUSTMENTS

Adjustments should be performed following this sequence:

- Pilot screw adjustment

- Carburetor synchronization and throttle slide height

(preliminary idle speed adjustment)

- Throttle cable adjustment

- Choke cable adjustment

- Final idle speed adjustment (engine running).

PILOT SCREW ADJUSTMENT

Completely close the pilot screw (until a slight seating resistance is felt) then back off as specified.

Turning screw clockwise leans mixture and conversely, turning it counter-clockwise enriches mixture.

Refer to “DIMENSIONS AND TOLERANCES” for the exact specifications.

1- Idle speed screw

2- Pilot screw (one on each carburetor)

Mikuni TM 40

Pilot jet 17.5 17.5 Air s crew 1.5 turns 1.5 turns Sli de cutaw ay 2.0 2.0 Needle 9DHI12-58-3 9DHI12-58-3 Main jet 380 380 Fuel le vel N/A N/A

---

Setting

MAG PTO

CARBURETOR SYNCHRONIZATION AND THROTTLE SLIDE HEIGHT (PRELIMINARY IDLE SPEED ADJUSTMENT)

FUEL SYSTEM 3 - 11

First proceed on PTO carburetor.

Use a drill bit to measure the throttle slide height (see table at right) on outlet side of carburetor (engine side).

1- Adjust PTO carburetor first

2- Drill bit used as a gauge to measure throttle height

3- Idle speed screw

Adjust by turning idle speed screw # 41.

Throttle slide height

Model

(drill bit size)

± 0.1 mm (±0.004'')

1.6 mm ( 0,063'')Snow hawk 600 HO 2004

For MAG carburetor, proceed using the synchronization screw. Use the same drill bit used for the PTO carburetor to measure throttle slide height. Turn synchronization screw to adjust.

1- PTO carburetor adjusted first

2- Drill bit used as a gauge to measure throttle height.

3- Synchronization screw

●

NOTICE:

Make sure that throttle cable does not hold the throttle slide. Loosen cable adjuster accordingly

Final idle speed adjustment (engine running at idle speed) should be within 1/2 turn of idle speed screw from preliminary adjustment.

FUEL SYSTEM 3 - 12

INSTALLATION

▼ CAUTION

Never allow throttle slide(s) to snap shut.

To re-install the carburetor, carry out the removal operations in the reverse order.

Be sure that the carburetor assembly is properly inserted into the engine intake sockets before tightening the two hose clamps. (A small amount of white grease can help here) After this, be sure to reconnect the black plastic carburetor support block to the lower shaft at the middle-bottom of the carburetor assembly.

THROTTLE CABLE ADJUSTMENT

Adjust throttle cable as per following procedure:

Loosen throttle cable housing adjusting and locking nuts.

Connect throttle cable barrel to carburetor cam lever # 40.

While holding throttle lever to wide open throttle position, pull on the throttle cable until mechanism touches the stopper. In this position, turn cable housing adjusting nut and tighten lock nut.

Also ensure that, when throttle is released to idle position, the idle adjusting screw end touches its stopper.

1- Throttle cable

2- Adjusting nut

3- Locking nut

CHOKE CABLE ADJUSTMENT

Adjust choke cable as per following procedure:

Loosen choke cable housing adjusting and locking nuts.

Connect choke cable on starter lever # 57.

While choke lever is fully open, pull choke cable until starter lever reaches the stopper. Tighten cable housing adjusting and locking nuts in this position.

As a confirmation, the gap between the stopper and the bracket should be within 0 and 0.5 mm (0 and 1/64 in).

FUEL SYSTEM 3 - 13

A - Within 0 and 0.5 mm (0 and 1/64 in)

Idle Speed Final Adjustment

Start engine and allow it to warm then adjust idle speed to specifications by turning idle speed screw clockwise to increase engine speed or counterclockwise to decrease it.

Refer to Chapter 15 – Dimensions and Tolerances for the specifications.

●

NOTICE: Do not attempt to set the idle speed by using the pilot screw. Severe engine dam-age can occur.

FUEL SYSTEM 3 - 14

FUEL PUMP

REMOVAL

Install a hose pincer (P/N 295 000 076) on fuel supply line close to pump inlet.

Disconnect fuel outlet line(s).

Disconnect impulse line.

Remove screws securing fuel pump to chassis.

PUMP VERIFICATION

Check fuel pump valves operation as follows:

Connect clean plastic tubing to the inlet nipple and alternately apply pressure and vacuum with pump of leak test kit. The inlet valve should re-lease with pressure and hold under vacuum.

Repeat the same procedure at the outlet nipple. This time the outlet valve should hold with pres-sure and also under vacuum.

Check impulse diaphragm and gasket as follows:

Connect clean plastic tubing to the impulse nipple and plug vent hole on top cover with a finger. Either applies pressure or vacuum using the pump (P/N 529 021 800) from the Engine leak tester kit. The diaphragm/gasket must not leak.

1- Pump

2- Plug vent hole

CLEANING AND INSPECTION

Check fuel pump valves operation as follows:

The entire pump should be cleaned with general-purpose solvent before disassembly.

Fuel pump components should be cleaned in general purpose solvent and dried with compressed air.

◆ WARNING

Solvent with a low flash point such as gasoline, naphtha, benzol, etc., should not be used as each is flammable and explosive.

FUEL SYSTEM 3 - 15

Inspect diaphragm. The pumping area should be free of holes, tears or imperfections. Replace as needed.

INSTALLATION

Inverse removal procedure.

◆ WARNING

Perform a pressure test to ensure there is no leak in the fuel system.

ENGINE REMOVAL 4-1

ENGINE REMOVAL

Unfasten or remove the following parts of the vehicle:

Remove the hood, bellypan and rear module from the vehicle. Removing the bellypan will require that you remove the ski as well.

Exhaust Pipe

o Remove the hose clamp retaining the exhaust pipe as

well as the two forward brackets (P/N’s SH032L and SH032R).

o Remove the four springs that hold the exhaust pipe tight

against the Y-manifold.

o Remove the two exhaust springs that hold the exhaust

pipe tight with the exhaust canister.

o Now free, pull the exhaust pipe forward to remove the

pipe completely from the vehicle.

o Plug the outlet of the Y-manifold with a clean cloth.

Front Fork

ENGINE REMOVAL 4-2

o Unfasten the tie rod end which connects the steering

column to the upper triple clamp.

o Unfasten the two fork pivot bolts that retain the fork to

the vehicle. The upper bolt is shown at right, the other is directly below it.

●

NOTICE:

Use a crate or box to support to support the vehicle just under the drive sprockets when removing the fork.

Recoil Starter

o Using a flat-head screwdriver, push the knot out of the

recess in the starter handle. Since it is often easier, cut the cord just before the knot while holding the cord securely such that it does not slip and go into the recoil housing. Make a new knot in the cord once the starter handle has been removed to prevent this from happening.

Fork Pivot Bolt

ENGINE REMOVAL 4-3

o Make a knot as shown at right.

Secondary Clutch

o Open the secondary clutch using the the spacer tool

(P/N 529 008 700). For more details, see Chapter 8 –

Primary Transmission System.

o Remove the bolt retaining the secondary clutch to the

jackshaft and then slide the secondary off the jackshaft at the same time removing the drive belt.

o Using the primary clutch holder tool (P/N 529 027 600),

remove the primary clutch bolt.

o Using the primary clutch puller (P/N 529 022 400)

remove the primay clutch from the engine.

Fuel Tank

o Remove the rubber latch retaining the fuel tank and

place it as shown on the right to have free access to the airbox and carburetors.

Airbox

o Loosen the too hose clamps that fasten the air box to

the rear of the carburetors and remove the airbox completely.

Carburetors

o Unfasten the black plastic clip that supports the bottom

of the carburetors. Push the top of it forward to snap it out of place. Rotate it sufficiently to allow clearance.

ENGINE REMOVAL 4-4

o Loosen the two hose clamps that fasten the carburetors

to the engine intake boots and then remove the carburetors completely, as a pair.

Engine Connector

o Cut the tie-wrap and disconnect the two-place housing

that connects the Crank Position Sensor (CPS) to the wiring harness (blue and white/yellow wires). This connector is located just above the jackshaft, near the ignition coil and the water pump oil reservoir.

o The engine-side of the Crank Position Sensor (CPS)

wire then passes down the height of the chassis – towards the magneto – and is attached to the tube that goes from the water pump oil reservoir to the water pump itself via a tie-wrap. Cut this tie-wrap as well.

ENGINE REMOVAL 4-5

o Cut the tie-wraps that secure the wires from the engine

to the voltage regulator. Then disconnect the four-place housing (yellow, yellow and yellow wires) and the twoplace housing (green and black wires) that is next to the four-place housing.

o Unplug the two wires from the two temperature sensors

located at the rear of the head of the engine.

Impulse Hose

o Disconnect the impulse hose from the crankcase of the

engine.

Water Pump Oil Resrevoir

ENGINE REMOVAL 4-6

o Using a drill and a 3/16 in. bit, drill out the two rivets that

secure the water pump oil reservoir to the MAG side chassis.

o Cut the tie-wrap that secures the choke cable to the oil

reservoir hose.

Cooling System

o Loosen the hose clamp that holds the forward cooling

hose to the water pump housing inlet at the front of the engine. With a bucket below this point, let the coolant drain from the system completely.

o Loosen the hose clamp on the reservoir end of the short

hose that runs from the head to the reservoir and disconnect the hose from the reservoir, as shown at right.

ENGINE REMOVAL 4-7

o Loosen the hose clamp farthest towards the PTO side

on the PTO side heat exchanger and disconnect the hose there. This hose runs from the head of the engine to the inlet of the tunnel-mounted heat exchangers and should remain connected to the engine when removing.

o Now that all of the peripheral equipment has been

disconnected, unscrew and remove the 4 bolts (per side) that secure the engine plate to each side of the chassis.

o PTO side bolts (x 4)

o MAG side bolts (x 4)

o Now the engine can be completely removed from the

vehicle.

Re-Installating Engine

To re-install the engine, follow the instructions above in the reverse order. However, pay close attention to the following details :

o Ensure that the 4 (per side) engine plate bolts are well

torqued to 37 N-m (27lbf-ft, 325 lbf-in). Loctite 243 is recommended here.

o Ensure the correct alignment of the clutches and the

preload/deflection of the drive belt.

o Ensure that each cable, wire and hose is properly

connected and its original routing is used. (See Chapter 17 – Wire, Cable and Hose Routing for more details.)

o Ensure that each coolant line is re-installed using the

original routing and that each hose clamp is well tightened.

o Re-fill the coolant reservoir to the Cold Level line before

attempting to start the vehicle. It is recommended to elevate the front of the vehicle about 12 in. off the ground when adding coolant to the system to ensure that all of the air bubbles will escape. See Chapter 6 –

Cooling System for more details.

ENGINE REMOVAL 4-8

REWIND STARTER

REWIND STARTER 5 - 1

REWIND STARTER 5 - 2

REWIND STARTER

1 420810865 1 Connecting flange

2 420241236 4 Socket head screw M6 x 16

3-12 420889764 1 Rewind starter

3 420811404 1 Starter housing

4 420939115 1 Rewind spring 5 420852286 1 Rope sheave

6 412500200 1 Starter rope (2200mm)

7 420852297 1 Pawl

8 420852305 1 Pawl lock

9 420847925 1 Stage sleeve

10 420250400 1 O-ring

11 420852520 1 Lock ring

12 420845560 1 Locking element 13 - 1 Positioning pin

14 420941256 4 Hex collar screw M6 x 20 15 420899763 @ Molykote PG 54, 10g 16 293530011 @ Sealant, Sikaflex black # 221 17 572084400 1 Starter grip

Part descriptionsRef. P/N Qty

INSPECTION

●

NOTICE:

Due to dust accumulation, rewind starter must be periodically cleaned, inspected and re-lubricated.

◆ CAUTION

It is of the utmost importance that the rewind starter spring be lubricated periodically using Molykote PG 54 (P/N 420 899

763). Otherwise, rewind starter component life will be shortened and/or rewind starter will not operate properly under very cold temperatures.

o Check if rope # 6 is fraying, replace if so.

o When pulling starter grip, mechanism must engage

within 30 cm (1 ft) of rope pulled. If not, disassemble rewind starter, clean and check for damaged plastic parts. Replace as required, lubricate, reassemble and recheck. Always replace O-ring # 10 every time rewind starter is disassemble.

REWIND STARTER 5 - 3

o When releasing starter grip, it must return to its stopper

and stay against it. If not, check for proper spring preload or damages. Readjust or replace as required.

O When pulling starter grip 10 times in a row, it must

return freely. If not, check for damaged parts or lack of lubrication. Replace parts or lubricate accordingly.

REMOVAL

o Using a small screwdriver, extract rope knot from starter

grip # 17. Cut rope close to knot. Tie a knot near starter.

o Remove screw # 14 securing rewind starter to engine

then remove rewind starter.

REWIND STARTER 5 - 4

ROPE REPLACEMENT

o Pull out rope. Hold rewind starter in a vise. Slide rope

and untie the knot. Pull out the rope completely.

1) Knot to be untied.

●

NOTICE:

When rope is completely pulled out, spring preload is 4 ½ turns.

DISASSEMBLY

o Undo knot previously tied at removal. Let sheave get

free to release spring preload.

o Cut locking element # 12 and discard. Remove lock ring

# 11, O-ring # 10, stepped sleeve # 9, Pawl lock # 8 and Pawl # 7.

o Remove sheave # 5 from starter housing # 3. Hold the

spring with a screwdriver.

o Pull out knot and then pull out rope # 6.

ASSEMBLY

At assembly, position spring # 4 outer end into spring guide notch then wind the spring counter clockwise into guide.

▼ WARNING

Since the spring is tightly wound inside the guide it may fly out when rewind is handled. Always handle with care.

1) Outer end into guide notch

◆ CAUTION

It is of the utmost importance that the rewind starter spring be lubricated periodically using Molykote PG 54 (P/N 420 899

763). Otherwise, rewind starter component life will be shortened and/or rewind starter will not operate properly under very cold temperatures.

o Lubricate spring assembly and 1cm (1/2 in) wide on

bottom of housing with Molykote PG 54.

1) Molykote PG 54

◆ CAUTION

REWIND STARTER 5 - 5

The use of standard multi-purpose grease could result in rewing starter malfunction.

o To install rope # 6, insert rope into sheave # 5 orifice

and lock it by making a knot, leaving behind a free portion of about 25 mm in length. Fuse rope end with a lit match and insert it into sheave.

o Free portion inserted into the sheave.

o Lubricate housing post with silicone compound grease.

Install sheave.

To adjust cord tension:

o Wind rope on the sheave and place the rope sheave

into the starter housing making sure that the sheave hub notch engages in the rewind spring hook.

o Rotate the sheave counter-clockwise until rope end is

accessible through rope exit hole. This will give ½ turn of preload.

o Pull the rope out of the starter housing and temporarily

make a knot to hold it.

REWIND STARTER 5 - 6

o Lubricate pawl # 7 with Molykote PG 54 (P/N 420 899

763) then install over rope sheave.

o Lubricate pawl lock # 8 with Molykote PG 54. Install

over pawl.

o Instal stepped sleeve # 9 with its sleeve first. Lubricate a

new O-ring # 10 and lock ring # 11 whit Molykote PG

54. Install over pawl lock.

1) Stepped sleeve

2) O-ring

3) Lock ring

o Install the locking element nut # 12.

INSTALLATION

o Fuse rope end with a lit match.

o Thread starter rope # 6 over guide pulleys and through

eye bolt.

o Reinstall rewind starter assembly on engine.

o Pass rope through starter grip # 17 and tie a knot in the

rope end. Insert rope end down and pull the starter grip over the knot.

COOLING SYSTEM

COOLING SYSTEM 6 - 1

COOLING SYSTEM 6 - 2

Cooling System

1 509000281 1 Coolant reservoir

2 509000187 1 Closure cap 3 SH-108SA 1 MAG side heat exchanger

4 SH-109SA 1 PTO side heat exchanger

5 SH-093 1 Coolant tube #4

6 SH-094 1 Coolant tube #3

7 SH-095 1 Coolant tube #1

8 SH-096 1 Coolant tube #5 9 SH-097 1 Coolant tube #2

10 - 1 Overflow tube

11 414554800 1 Spring clamp (black)

12 408800400 10 Hose clamp (geared)

- 278001016 1 Temperature sensor (Bosch, Blue, MAG side)

- 512047000 1 Temperature sensor (Indebras, Black, PTO side)

- 420922517 1

- 420931272 1 Thermostat sealing ring

Thermostat (42

Part descriptionsRef. P/N Qty

)

◆ WARNING

COOLING SYSTEM LEAK TEST

o Install special radiator cap (P/N 529021400) included in

engine leak tester kit (P/N 861749100) on coolant tank.

o Install hose pincher (P/N 295000076) on the overflow

hose. Using pump also included in the kit and pressurize the entire system through the coolant reservoir to 100 kPa (15 PSI).

o Check all hoses and cylinder/base for coolant leaks.

Spray all connections with a soapy water solution and look for air bubbles.

INSPECTION

Check the general condition of hoses and clamp tightness.

DRAINING THE SYSTEM

To drain the cooling system:

o Siphon the coolant mixture from the coolant tank.

o Disconnect the hose at the water pump inlet housing to

drain coolant from engine.

o When the coolant level is low enough, lift the rear

of the vehicle to drain the heat exchangers.

COOLING SYSTEM 6 - 3

◆ WARNING

Never drain or refill the cooling system when the engine is hot.

DISASSEMBLY AND ASSEMBLY

Temperature sensors:

o Apply Loctite 592 (P/N 413 702 300) thread sealant to

temperature sensor threads to avoid leakage.

COOLING SYSTEM 6 - 4

Pressure Cap (No. 2):

o Check if the cap pressurizes the system. If not,

install a new 90 kPa (13 PSI) cap (do not exceed this pressure).

Thermostat:

To check the thermostat, put it in a basin of water and gradually heat it. The thermostat should start to open when water temperature nears 42°C (108°F). It will be almost fully open at 50°C (122°F).

The thermostat is a double action type:

(1) Its function is to give faster warm up of the engine by

controlling a circuit; water pump — engine — coolant tank. This is done by bypassing the heat exchanger radiator circuit and using what it called a short circuit during warm up, i.e. before the coolant temperature reaches 42°C (108°F).

(2) When the liquid is warmed enough, the thermostat

progressively opens the circuit; water pump — engine — heat exchangers — coolant tank to keep the liquid at the desired temperature. (See the diagram of the exploded view on page 6-1).

These 2 functions have the advantage of preventing a massive entry of cold water into the engine.

COOLING SYSTEM REFILLING PROCEDURE

▼ CAUTION

To prevent the formation of corrosion or freezing, always re-fill the system with the recommended premixed coolant.

REFILLING PROCEDURE

●

NOTICE:

Use the 50/50 premixed coolant rated for -37°C (- 35°F) (P/N 293 600 038).

o Do not reinstall pressure cap.

o With engine cold, refill coolant tank up to COLD LEVEL

line.

o Start engine. Refill up to line while engine is idling until

rear heat exchangers are warm to the touch (about 4 to 5 minutes).

o Always monitor coolant level while filling tank to avoid

emptying.

o Install pressure cap.

o Lift rear of vehicle and support it safely.

o Blip the throttle 3 - 4 times to bring engine speed to 7000

RPM.

o Apply the brake to stop the track.

o Lower vehicle back on ground and add coolant up to 15

mm (1/2 in) above the COLD LEVEL line, as shown at right.

o Lift front of vehicle approximately 60 cm (24 in) and

support it safely. Let the vehicle idle for two minutes like this

o Put the vehicle back on the ground and add coolant up to

15 mm (1/2 in) above the COLD LEVEL line.

o When the engine has completely cooled down, recheck

coolant level in coolant tank and refill up to the line if needed.

o Check for coolant mixture freezing point. The

specification is - 37°C (- 35°F). Adjust as necessary.

COOLING SYSTEM 6 - 5

ENGINE / BOTTOM END

ENGINE (CYLINDERS / HEAD / BASE) 7 - 1

29 N-m ( 21.5 lbf-ft

3.0 kg-m, 258 lbf-in)

1-12

14-20

ENGINE (CYLINDERS / HEAD / BASE) 7 - 2

Engine / Bottom End

Ref. P/N Qty Part Descriptions

1-12 420889083 1 Crankcase ass‘y

2 420640836 10 Hex. collar screw M8 x 75 3 420640431 6 Hex. collar screw M8 x 45 4 420640311 2 Hex. collar screw M6 x 45 5 205063044 1 Socket head screw M6 x 30 6 420941925 2 Screw M5 x 16 7 420840401 2 Socket head screw M6 x 22 8 290632010 2 Dowel pin

9 420860965 1 Cable Grommet 10 420960770 2 Cap 11 420960777 1 Cap 12 420232100 1 Ball Bearing 13 420956510 2 Check Valve

14-20 420837421 1 Water Pump Assy

15 - 1 Step Collar 16 420230195 1 Oil Seal 17 420232100 1 Ball Bearing 18 420650370 1 Oil Seal 19 420950890 2 O-Ring 20 - 1 Water Pump Shaft 21 420840511 2 Socket Head Screw M5 x 16 22 420227945 1 Washer 23 420222505 1 Water impeller 24 420931810 1 Gasket 25 420922630 1 Water pump housing 26 420240031 6 Hex screw M6 x 25 27 420230400 1 O-ring 28 420931565 1 Gasket 29 420810825 1 Block-off plate 30 414413800 - Oil Line 31 420938190 1 Clamp 32 420059340 - Short Block Assy 593HO 33 293800060 10mL Loctite 243 34 413711400 10mL Loctite 648 35 413707000 - Molykote 111 36 420899271 400g Petamo Grease, GHY133N 37 420297906 30mL Sealing compound 3

413802900 12 x 1L Injection Oil

ENGINE (CYLINDERS / HEAD / BASE) 7 - 3

Engine / Bottom End

Ref. P/N Qty Part Descriptions

39 420974535 - Oil Line 40 420874370 1 Reducer fitting 41 420956239 - Oil Line 42 420951260 1 Clamp 43 420951240 1 Clamp 44 420960279 1 Cap

45-47 420956240 1 Oil Reservoir Assy

46 420850350 1 Rubber Gasket 47 420956250 1 Oil Cap 48 420812420 1 Oil Seal Cover 49 420941430 4 Countersunk screw M6 x 20

ENGINE (CYLINDERS / HEAD / BASE) 7 - 4

ENGINE / CRANKSHAFT AND PISTONS

ENGINE (CYLINDERS / HEAD / BASE) 7 - 5

Engine / Crankshaft and Pistons

Ref. P/N Qty Part Descriptions

1 - 9 420889090 1 Crankshaft Assy

2 420832635 1 Brg. 6207 3 420832575 1 Brg. 6207 4 420931792 1 Oil Seal 5 420832606 1 Brg. 6 420926190 1 Washer 7 420832600 1 Brg. 8 420931285 1 Oil Seal

9 420246015 1 Woodruff key 10 420945759 1 Lock Washer 22mm 11 420842230 1 Hex Nut M22 12 420832425 2 Needle Brg.

13-14 420889181 2 Piston Assy (71.89mm)

14 420815290 2 Semi-trapez ring 15 420916410 2 Gudgeon pin 16 420845106 4 Piston Circlip 17 420832575 1 Brg. 6207 18 420931455 2 Oil Seal 19 420834355 1 Central Gear (15 teeth) 20 420819709 1 Crankshaft (PTO section) 21 420819739 1 Crankshaft (MAG section) 22 420889093 1 Rod Repair Kit (MAG)

- 420889094 1 Rod Repair Kit (PTO) 23 293800060 10mL Loctite 243 24 293800070 8oz Loctite 767, anti-seize lubricant 25 413711400 10mL Loctite 648 26 420899271 400g Petamo Grease, GHY133N 27 293550021 50g Isoflex Grease 28 413802900 12 x 1L Injection Oil

ENGINE (CYLINDERS / HEAD / BASE) 7 - 6

ENGINE / TOP END

ENGINE (CYLINDERS / HEAD / BASE) 7 - 7

Ref. P/N Qty Part Descriptions

Engine / Top End

1 420931895 1 Base Gasket 0.8 mm

420931894 - Base Gasket 0.7 mm 420931892 - Base Gasket 0.6 mm

420931893 - Base Gasket 0.5 mm 2 420613710 2 Nicasil Cylinder 3 420854650 2 Exhaust Valve Guillotine 4 420430110 2 O-ring 5 420931542 2 Gasket 6 420854455 2 Valve Housing 7 205062544 4 Socket head screw M6 x 25 8 420260729 2 Bellows 9 420838253 2 Spring Clamp

10 420854449 2 Exhaust Valve 11 290239048 2 Hose Spring 12 420239944 2 Spring 13 290911558 2 Valve Cover 14 420430220 2 O-ring 15 420241221 2 Adjuster Screw 16 420241270 4 Screw M5 X 25 17 420640524 4 Hex collar screw M10 x 80 18 420640534 4 Hex collar screw M10 x 120 19 420931590 2 Rubber Ring Seal 20 293300026 2 O-ring 21 420613700 1 Cylinder Head (Silver) 22 290950320 1 O-ring 23 420430782 2 O-ring 24 420923460 1 Cylinder Head Cover (Silver) 25 420841306 10 Hex collar screw M8 x 65 26 420941621 2 Hex collar screw M8 x 56.5

27 420922517 1

Thermostat (42

C) 28 420931272 1 Sealing Ring 29 420922025 1 Outlet Socket 30 420941250 3 Screw M6 x 20 31 420850338 1 Gasket 32 420922062 1 Curved Neck Outlet 33 420240480 1 Plug Screw 1/8-27 NPT 34 420941451 1 Hex collar screw M8 x 40

35-38 420867879 2 Intake Socket Assy

36 420924680 4 Reed Petal 37 420924695 4 Reed Petal Stop 38 42094121

12 Screw M3 x

ENGINE (CYLINDERS / HEAD / BASE) 7 - 8

Engine / Top End

Ref. P/N Qty Part Descriptions

39 420941925 12 Screw M5 x 16 40 420850552 2 Gasket 41 420673070 1 Exhaust Manifold 42 420889920 1 Engine Gasket Set

43 420889925 1 Cyliinder Gasket Set 44 420297906 30mL Sealing Compound 45 293800038 50mL Loctite 518

TOP END

●

NOTICE:

The engine must be removed from the chassis to carry out the following operations. See Chapter 4 – Engine Removal for details.

TROUBLESHOOTING

Before completely disassembling the engine, check airtightness. Refer to the section named LEAK TEST AND ENGINE DIMENSION MEASUREMENT at the end of this chapter.

CLEANING

o Discard all gaskets and O-rings. o Clean all metal components in a non-ferrous metal

cleaner.

o Scrape off carbon formation from cylinder exhaust

port cylinder head and piston dome using a wooden spatula.

●

NOTICE: The letters “AUS” (over an arrow on the piston dome) must be visible after cleaning.

o Clean the piston ring groove with a groove cleaner

tool or with a piece of broken ring.

DISASSEMBLY

RAVE System

ENGINE (CYLINDERS / HEAD / BASE) 7 - 9

●

NOTICE: RAVE stands for Rotax Adjustable Variable Exhaust.

o Remove spring clip or screws no. 16, cover no. 13

and spring no. 12.

o Remove spring no. 11. o Unscrew valve piston no. 10. o Remove bellows no. 8 and spring no. 9. o Remove cylindrical screws. Remove valve housing

no. 13.

o Pull out exhaust valve no. 3. (see right)

2, Cylinder

Remove spark plugs, coolant outlet no. 32. Unscrew cylinder head cover no. 24 then cylinder head no. 21.

13, Piston

Place a clean cloth or rubber pad (P/N 529 023 400) over crankcase. Then with a pointed tool inserted in piston notch, remove both circlips no. 16 from piston no. 13.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 10

All engines are equipped with cageless piston pin Bearings, as shown at right.

Once the head and cylinder(s) has been removed, Use piston pin puller (P/N 529 035 503) along with 20 mm sleeve kit (P/N 529 035 542). Use also a locating sleeve.

●

NOTICE:

The locating sleeve is the same that contains new cageless bearing.

Insert piston pin puller (P/N 529 035 503) making sure it sits squarely against piston as shown at right.

Install sleeve (1) then shouldered sleeve (2) over puller rod as shown at right.

Screw in (LH threads) extracting nut.

Pull out piston pin no. 15 by unscrewing puller until shouldered sleeve end is flush with thrust washer of piston pin bearing.

Remove puller. Pull out shouldered sleeve carefully.

Remove piston from connecting rod.

Install locating sleeve. Then push the needle bearings, thrust washers and sleeve into the upper connecting rod journal

ENGINE (CYLINDERS / HEAD / BASE) 7 - 11

ENGINE (CYLINDERS / HEAD / BASE) 7 - 12

INSPECTION

●

NOTICE:

For details, Refer to LEAK TEST AND ENGINE DIMENSIONS MEASUREMENT AT THE END OF THIS CHAPTER.

RAVE System

Check valve rod housing and cylinder for clogged passages.

●

NOTICE: Oil dripping from draining hole (No. 1) indicates a loose spring or damaged bellows.

8, Bellows

Check for cracked, dried or perforated bellows.

12, Spring

ASSEMBLY

RAVE System

Install RAVE valve (noting which is the top side when it was removed) Tighten red cap no. 15 screw to bottom.

2,13, Cylinder and Piston

Before inserting piston in cylinder, lubricate the cylinder with new injection oil or equivalent.

24,21,2, Cylinder Head Cover, Cylinder Head and Cylinder

Make sure parts sealing surfaces are flat. Refer to LEAK TEST AND ENGINE DIMENSION MEASUREMENT at the end of this chapter and look for CYLINDER HEAD WARPAGE.

When installing a new cageless bearing, replace half plastic cages with sleeve.

●

NOTICE: All 593 HO engine cageless bearings have 28 needles.

o Oil needle bearing with injection oil.

o Grease thrust washers and install them on each end of

needles. The grease will help to hold them in place.

o Insert cageless bearing into connecting rod.

o Heat piston with a 100 W lamp or a heat gun before

piston installation to make the insertion of the pin much easier.

▼ CAUTION

Piston temperature must not exceed 46°C (115°F). Never use direct flame to heat the piston and never freeze the pin.

At assembly, place the pistons over the connecting rods with the letters “AUS” (over an arrow on the piston dome) facing towards the exhaust port.

1. Exhaust

Install shouldered sleeve.

Install piston pin puller and turn handle until piston pin is correctly positioned in piston.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 13

ENGINE (CYLINDERS / HEAD / BASE) 7 - 14

All Models

▼ CAUTION

Always install new circlips. To minimize the effect of acceleration forces on circlip, install each circlip so the circlip break is at 6 o’clock as illustrated. Use appropriate piston circlip installer.

Use circlip installer (P/N 529 035 686) to install new mono-hook circlips no. 16. Insert circlip into support so that, when installed in piston groove, the tab faces upward.

With round end of pusher, position circlip perpendicularly to the support axis.

With the other end of the pusher, push circlip into the support groove.

Using a plastic hammer, tap the pusher to put the circlip in place. Make sure to install new circlips with the tab toward the top as per the following photos.

▼ CAUTION

Always install new mono-hook circlips. If circlip installation fails at the first attempt, always retry with a new one because, on a second attempt, the circlip will lose its normal retaining capabilities.

▼ CAUTION

Circlips must not move freely after installation; if so, replace them. Clean cylinders and crankcase mating surfaces with Loctite Chisel (P/N 413708500). Coat crankcase mating surface with Loctite 518 (P/N

293800038). Choose the right gasket thickness according to combustion chamber volume. Refer to LEAK TEST AND ENGINE DIMENSION MEASUREMENT. Install it on the crankcase. Coat gasket with Loctite 518.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 15

▼ CAUTION

Always install a gasket of the proper thickness. Failure to do so may cause detonation and severe engine damage. Before inserting piston in cylinder, lubricate the cylinder with new injection oil or equivalent. Install cylinders. Do not tighten. Install new rubber ring and round O-rings on each cylinder.

●

NOTICE: Carefully clean screws before reinstallation, specifically under screw head.

Install exhaust manifold with gaskets. Do not tighten yet.

Torque cylinder screws in a crisscross sequence as per the following table:

ENGINE (CYLINDERS / HEAD / BASE) 7 - 16

At assembly, torque cylinder head screws to 29 N-m (21 Ibf-ft) in the illustrated sequence at right.

Tighten exhaust manifold bolts to 23 N-m (17 lbf-ft) in a crisscross sequence.

Apply Loctite 243 (P/N 293 800 060) on screws threads. Install outlet socket and tighten screws to 12 N-m (106 Ibf-in). Note position of longer screw.

1. Longer screw

35, Reed Valve

All Engines

Blades have a curved shape. Install with their curve facing reed block.

With blade stopper no. 37 removed, check reed valve for proper tightness. There must not be any play between blade and valve body when exerting a finger pressure on blade at blade stopper location.

In case of a play, turn blade upside down and recheck. If there is still a play, replace blade and/or valve body.

Check distance from blade stopper outer edge and distance from center of reed valve block.

TYPICAL A. 18.7 - 0, + 0.75 mm (.736 - 0, + .030 in)

Bend blade stopper as required to obtain the proper distance.

Blade stoppers may slightly interfere with cylinder during installation. Adjusted distance will be reduced automatically upon installation.

BOTTOM END

●

NOTICE:

The engine must be removed from the chassis to carry out the following operations. See Chapter 4 – Engine Removal for details.

CLEANING

o Discard all gaskets and O-rings. o Clean all metal components in a non-ferrous metal

cleaner. Use gasket remover (P/N 413708500) accordingly.

o Remove old paste gasket material from crankcase

mating surfaces with gasket remover (P/N 413708500)

▼ CAUTION

Never use a sharp object to scrape away old sealant as score marks incurred are harmful to crankcase sealing.

DISASSEMBLY

General

To remove drive pulley, refer to Chapter 8 – Primary Transmission System. To remove magneto, refer to CDI

SYSTEM in Chapter 14 – Electrical System.

2,3,5,7 Crankshaft Bearings

To remove bearings from crankshaft, use a protective cap and special puller, as illustrated.

1. PTO side

2. MAG side

This includes the following parts:

P/N Description

420940755 M16x1.5x150 Screw 420840681 M8x40 Screw (4) 420841201 M8x70 Screw (4)

Crankshaft protector PTO All engines

420876552

420876557

420977490 420977475 Half Ring (2) For 72mm OD brgs. 420276025 Half Ring (2) For 62mm OD brgs. 420977480 Puller Ring

420977494 420977479 Half Ring (2) For 80mm OD brgs. 420876330 Half Ring (2) For 52mm OD brgs.

except 247 Crankshaft protector MAG All engines except 247 Puller Ring (Use with half rings 420977475 or 420276025)

Puller Ring (Use with half rings

420977479)

ENGINE (CYLINDERS / HEAD / BASE) 7 - 17

ENGINE (CYLINDERS / HEAD / BASE) 7 - 18

INSPECTION

NOTE: Refer to LEAK TEST AND ENGINE DIMENSIONS MEASUREMENT (End of this chapter)

ASSEMBLY

Coat lip of all seals with Petamo grease (P/N 420 899 271).

5, Crankshaft Bearing

Smear anti-seize lubricant (P/N 413 701 000) on part of crankshaft where bearing fits.

Prior to installation, place bearings into an oil container filled with injection oil previously heated to 75°C (167°F). This will expand the bearing and ease installation.

Some bearings must be lubricated with Isoflex grease (P/N 293 550 021).

▼ CAUTION

Use only the recommended Isoflex grease. Make sure not to push Isoflex grease between outside bearing race and half crankcase. Use a sharp object to scrape away old sealant as score marks incurred are harmful to crankcase sealing.

●

NOTICE:

The 50 g tube corresponds to 50 cc of grease.

Put 50 to 55 mL of grease in a syringe.

▼ CAUTION

Do not exceed the recommended amount of grease.

Fill inner side of PTO side bearing with Isoflex grease (about 10 mL) as shown at right.

With the syringe, fill the outer ball bearing and inner side of outer seal with 40 to 45 mL of Isoflex grease as shown at right.

Apply 6 mL of grease to MAG side outer bearing.

●

NOTICE:

If replaced with new bearing, do not apply grease as new bearings come with grease already applied.

At crankshaft installation, position drive pins as illustrated.

1. Position pins

Pour 50 mL (2 U.S. oz) of injection oil in the pan under central gear to lubricate pump gearing as per photo.

1. Oil bath

Crankcase Assembly

IMPORTANT: The total assembly sequence, including sealing

compound spreading, screwing and torquing of bolts according to the proper sequence, must be performed within 10 minutes. Do

not wait between each bolt torquing. All bolts must be torqued in a row.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 19

ENGINE (CYLINDERS / HEAD / BASE) 7 - 20

Before screwing together both parts of crankcase, seal it with sealing compound (P/N 420 297 906). Make sure surfaces are perfectly clean and degreased before applying sealing compound.

Spread a seam of 1.2 mm (1/16 in) maximum in diameter on the surface of lower crankcase half.

As far as possible, sealing compound must be applied in one run to avoid any risks of leakage through the crankcase.

Screw all crankcase bolts in place in the following sequence and to the appropriate torque; this must be done in two steps, torquing: first, screw bolts up to 60% of the final torque (18 N-m (13.5 lbf-ft) for most of the bolts), then, tighten to the required torque (i.e. 29 N-m (21 lbf-ft)).

A. Torque bolts 1 through 16 to 29 N-m (21 lbf-ft) B. Torque bolts 17 through 21 to 9 N-m (80 lbf-in)

BREAK-IN

After rebuilding an engine, always observe a break-in period as described in Chapter 1 – General Instructions.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 21

ENGINE (CYLINDERS / HEAD / BASE) 7 - 22

LEAK TEST AND ENGINE MEASUREMENT

LEAK TEST

The following gives verification procedures for 593 HO engines.

PREPARATION

1. Remove tuned pipe.

2. Install plug over exhaust manifold.

3. Remove carburetors.

4. Insert plugs in intake rubber boots. Tighten with existing clamps.

5. Using a hose pincher (P/N 295 000 076), block impulse hose.

6. Install air pump on exhaust plug.

●

NOTICE:

If necessary, lubricate air pump piston with mild soap.

▼ CAUTION

Using hydrocarbon lubricant (such as engine oil) will damage rubber seal of pump piston.

7. Activate pump and pressurize engine to 34 kPa (5 PSI). Do not exceed this pressure.

8. Engine must stand this pressure during 3 minutes.

– If pressure drops before 3 minutes, check tester kit by spraying a soapy solution on pump cylinder, all plugs and fittings.

– If tester kit is leaking, bubbles will indicate where leak comes from.

– If tester kit is not leaking, check engine as per the following procedure.

PROCEDURE

●

NOTICE: A flow chart has been prepared as a visual reference. Page 7-25 and 7-26 of this chapter.

Using the flow chart and the following text, pressurize area to be tested and spray soapy solution at the indicated location.

– If there is a leak at the tested location, it is recommended to continue testing the next item before overhauling the engine. There is a possibility of more than one leak.

– If there is no leak at the tested location, continue pumping to maintain pressure and continue with the next item until the leak is found.

Engine

Check the following:

1. All jointed surfaces and screw/stud threads of engine:

– spark plug base, insulator – cylinder head – RAVE valve bellows, piston and housing – cylinder – crankcase halves (joint) – oil injection pump mounting flange (O-ring) – coolant pump housing – bleed screws/plugs.

2. Remove cooling system cap.

Check for air bubbles in antifreeze. It indicates defective cylinder head O-ring or cylinder base gasket.

3. Remove drive pulley then check crankshaft outer seal.

4. Remove rewind starter and magneto system then check crankshaft outer seal.

5. Check pump shaft gear oil reservoir.

Pump Shaft Oil Gear Reservoir

Install air pump on adapter and pressurize as shown at right. If pressure drops, it indicates a defective crankshaft inner seal.

CRANKSHAFT INSTALLED IN UPPER HALF CRANKCASE

1. Crankshaft inner seal on PTO side

2. Crankshaft inner seal on MAG side

ENGINE (CYLINDERS / HEAD / BASE) 7 - 23

ENGINE (CYLINDERS / HEAD / BASE) 7 - 24

1. Check weep hole below coolant pump housing with soapy water.

1. Weep hole

If there is a leak, it indicates that a pump shaft is defective (oil seal beside coolant ceramic seal).

2. Leaks can be also on the oil pump side, which is blocked off on the Snow Hawk 600HO. Check this mounting area and the two mounting bolts for leaks.

3. If leak still persists, it indicates a defective casting somewhere in the engine.

Disassemble engine and carefully check for defects in castings. Pay attention to tapped holes which may go through engine sealed area and thus lead to leakage.

FINALIZING REASSEMBLY

After reassembling engine, always recheck for leakage.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 25

CHECK FOR OIL LEAKS AROUND OIL

PUMP BLOCK-OFF PLATE

OIL LEAKING FROM AROUND

EDGES OF BLOCK-OFF PLATE?

REPLACE GASKET

ENGINE (CYLINDERS / HEAD / BASE) 7 - 26

ENGINE DIMENSION MEASUREMENT

This section covers the 593HO engine type.

CYLINDER HEAD WARPAGE

ENGINE (CYLINDERS / HEAD / BASE) 7 - 27

Check gasketed surface of the cylinder head with a straightedge and a feeler gauge.

CYLINDER TAPER

Compare cylinder diameter 16 mm (5/8 in) from top of cylinder to just below its intake port area. If the difference exceeds the specified dimension the cylinder should be rebored and honed or should be replaced. Nikasil cylinder can be honed using diamond hone but cannot be rebored.

●

NOTICE: Be sure to restore the chamfer around all cylinder sleeve port openings.

1. Below the intake port A. 16 mm (5/8 in) from top

CYLINDER OUT OF ROUND

ENGINE (CYLINDERS / HEAD / BASE) 7 - 28

Measuring 16 mm (5/8 in) from top of cylinder with a cylinder gauge, check if the cylinder out of round is more than the specified dimension. If larger, cylinder should be rebored and honed or should be replaced. Nikasil cylinder can be honed using diamond hone but cannot be rebored.

●

NOTICE: Be sure to restore the chamfer around all cylinder sleeve port openings.

1. Piston pin position

2. Measures to be compared A. 16 mm (5/8 in)

COMBUSTION CHAMBER VOLUME MEASUREMENT

The combustion chamber volume is the region in the cylinder head above the piston at Top Dead Center. It is measured with the cylinder head installed on the engine.

1. Combustion chamber

●

NOTICE: When checking the combustion chamber volume, engine must be cold, piston must be free of carbon deposits and cylinder head must be leveled.

1. Remove both spark plugs and bring one piston to Top Dead Center a using a TDC gauge.

1. Bring piston to TDC

2. Remove cylinder head.

3. Seal piston ring gap with a small amount of grease.

4. Reinstall cylinder head.

5. Obtain a graduated burette (capacity 0 - 50 cc) and fill with an equal part (50/50) of gasoline and injection oil.

1. Graduated burette (0 - 50 cc)

6. Open burette valve to fill its tip. Add liquid in burette until level reaches 0 cc.

7. Inject the burette content through the spark plug hole until liquid touches the top spark plug hole.

. Top of spark plug hole

ENGINE (CYLINDERS / HEAD / BASE) 7 - 29

●

NOTICE: The liquid level in cylinder must not drop for a few seconds after filling. If so, there is a leak between piston and cylinder. The recorded volume would be false. Reseal the piston ring gap and follow the instruction provided above.

8. Let burette stand upward for about 10 minutes, until liquid level is stabilized.

9. Read the burette scale to obtain the quantity of liquid injected in the combustion chamber.

●

NOTICE: When the combustion chamber is filled to top of spark plug hole, it includes an amount of 2.25cc corresponding to the spark plug well.

10. Repeat the procedure for the other cylinder.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 30

11. Install a thicker or thinner cylinder/crankcase gasket (refer to Parts Catalogs) in order to obtain the specified combustion chamber volume or the nearest.

USED PISTON MEASUREMENT

Note the measurement on the piston dome.

1. Piston dome

2. Piston measurement

Using a micrometer, measure piston skirt at 15 mm (.590 in) perpendicularly (90°) to piston pin.

1. Measuring perpendicularly (90°) to piston pin axis A. 15 mm (.590 in)

The measured dimension must not be less than 0.15 mm (.006 in) of the one scribed on piston dome. Otherwise, install a new piston.

CYLINDER/PISTON CLEARANCE

Used and New Pistons

IMPORTANT: Make sure used piston is not worn more than

specified. See USED PISTON MEASUREMENT above.

Take the measurement on the piston dome.

1. Piston dome

2. Piston measurement

Adjust and lock a micrometer to the specified value on the piston dome.

1. Micrometer set to the piston dimension

With the micrometer set to the piston dimension, adjust a cylinder bore gauge to the micrometer dimension and set the indicator to

1. Use the micrometer to set the cylinder bore gauge

2. Dial bore gauge

ENGINE (CYLINDERS / HEAD / BASE) 7 - 31

ENGINE (CYLINDERS / HEAD / BASE) 7 - 32

1. Indicator set to 0 (zero)

IMPORTANT: Always remove cylinders from crankcase before measuring.

Position the dial bore gauge at 16 mm (5/8 in) below cylinder top edge.

1. Measuring perpendicularly (90°) to piston pin axis A. 16 mm (5/8 in)

Read the measurement on the cylinder bore gauge. The result is the exact piston/cylinder wall clearance. If clearance exceeds specified tolerance, replace cylinder.

●

NOTICE: Make sure the cylinder bore gauge indicator is set exactly at the same position as with the micrometer, otherwise the reading will be false.

IMPORTANT: The total piston/cylinder clearance (actual cylinder diameter minus actual piston skirt diameter) should be within 0.30 mm (.012 in).

RING/PISTON GROOVE CLEARANCE

Using a feeler gauge check clearance between rectangular ring and groove. Replace piston if clearance exceeds specified tolerance. Refer to Chapter 15 – Dimensions

and Tolerances..

RING END GAP

Position ring half-way between transfer ports and intake port.

●

NOTICE: In order to correctly position the ring in the cylinder, use piston as a pusher.

Using a feeler gauge, check ring end gap. Replace ring if gap exceeds specified tolerance. Refer to Chapter 15 – Dimensions and Tolerances.

1. Transfer port

2. Intake port

CRANKSHAFT DEFLECTION

Crankshaft deflection is measured with a dial indicator.

Measuring (in crankcase)

First, check deflection with crankshaft in crankcase. If deflection exceeds the specified tolerance, recheck deflection using Vshaped blocks to determine the defective part(s). See below.

Measuring (on bench)

Once engine is disassembled, check crankshaft deflection on Vshaped blocks. If deflection exceeds the specified tolerance, it can be worn bearings or a bent crankshaft. Remove crankshaft bearings and check deflection again on V-shaped blocks to determine the defective part(s). See measurement A in following illustration.

1. Measure at mid point between the key and the first thread A. 3 mm (1/8 in)

ENGINE (CYLINDERS / HEAD / BASE) 7 - 33

ENGINE (CYLINDERS / HEAD / BASE) 7 - 34

●

NOTICE: Crankshaft deflection cannot be correctly measured between centers of a lathe.

If the deflection exceeds the specified tolerance, crankshaft should be repaired or replaced.

Using a feeler gauge, measure distance between thrust washer and crankshaft counterweight. If the distance exceeds specified tolerance, repair or replace the crankshaft.

CRANKSHAFT END-PLAY

End-play is not adjustable but it should be between 0.10 - 0.30 mm (.004 - .012 in).

CHECKING CRANKSHAFT ALIGNMENT

o Install a degree wheel (P/N 529 035 607) on crankshaft

end.

o Remove both spark plugs.

o Install a TDC gauge (P/N 414 104 700) in spark plug hole

on MAG side.

o Bring MAG piston to top dead center.

o Rotate degree wheel (not crankshaft) so that 360° mark

aligns with center of crankcase. Scribe a mark on crankcase.

o Remove TDC gauge and install it on center cylinder.

o Bring PTO piston to top dead center. Degree wheel must

rotate with crankshaft.

Interval between cylinders must be 180° ± 0.5. Any other reading indicates a misaligned (twisted) crankshaft.

ENGINE (CYLINDERS / HEAD / BASE) 7 - 35

PRIMARY TRANSMISSION SYSTEM 8-1

PRIMARY TRANSMISSION SYSTEM / PRIMARY CLUTCH

10 N-m (1 kg-m ,

7.4 lbf-ft, 125 lbf-in)

90 N-m (9.2 kg-m , 66 lbf-ft, 797 lbf-in)

PRIMARY TRANSMISSION SYSTEM 8-2

Ref. P/N Qty Part Descriptions

1-14 0400-0152 1 Primary Clutch Assembly

Primary Transmission System / Primary Clutch

1 0405-0071 1Fixed sheave 2 0410-0022 1 Sliding sheave 3 4 5 6 7 8

9 10 11 12 13 14 15 16

0150-1014 0440-2018 1 Spring Compression Limiter 0151-1007 1 Spring 0440-0005 1 Spring Cover

420-2453-700 3 Lock Washer

0080-0021 3 Socket Head Screw 0130-3006 3 Slider Block

X-81-3 15 Mass (small)

0135-3001 3 Mass (large)

X-7 3 Threaded Cap 0130-0153 3 0115-3042 1 Plated Cover (D1) 0080-0162 1 Machined Washer

V16J1 1 Nut

Spring seat

rm Assembl

Snow Hawk 600HO Set-up, Service And Shop Manual

Specifications and Main Features

Frequently Asked Questions

User Manual