Page 1

INDEX GENERAL INFORMATION PERIODIC INSPECTION AND ADJUSTMENT CHASSIS POWER TRAIN ENGINE OVERHAUL CARBURETION ELECTRICAL APPENDICES

.I ENG

• .,

CARB

Iii

ELEC

APPX


Q)

ILLUSTRATED SYMBOLS

®

I~EF~I~I Irgjl~1 @

®

I IENGIJiI ICARSI'I

(Refer to the illustration) Illustrated symbols Q) to ® are designed as thumb tabs to indicate the chapter's number and content.

ICHASI~ ~141

® ®

®

® ®

®

(J)

Q) General information @

(J)

®

Periodic inspection and adjustment Chassis Power train Engine Carburetion Electrical Appendices

®

IElEC I iiii I IAPPXI~'1 ®

(jJ)

@

@

@

@

~ ~

§ 1 m

@

®

~ ~ [ml

@

@

Gl @)

~ ~ ®

1

1

Gl @

~

A @a @a

Illustrated symbols ® to ® are used to identify the specifications which appear.

® @ (jJ) @ @

®

Filling fluid Lubricant Tightening Wear limit, clearance Engine speed Q,V,A

Illustrated symbols @ to ® in the exploded diagrams indicate the grade of lubricant and the location of lubrication points.

@ @ @ @ @)

®

Apply engine oil Apply gear oil Apply molybdenum disulfide oil Apply low-temperature lithium-soap base grease Apply wheel bearing grease (Esso-Beacon 325 grease or Aero Shell grease #7) Apply molybdenum disulfide grease

Illustrated symbols ® to @ in the exploded diagrams indicate the grade of sealing or locking agent and the location of application points.

®

Apply locking agent (LOCTITE®)

@ Apply Yamabond No. 4® @ Apply Yamabond No.5®


_______________ I~1=~I..1 CHAPTER 1. GENERAL INFORMATION MACHINE IDENTIFICATION ............................. 1-1 FRAME SERIAL NUMBER ........................... 1-1 ENGINE SERIAL NUMBER ......................... 1-1 IMPORTANT INFORMATION ........................... 1-2 ALL REPLACEMENT PARTS ....................... 1-2 GASKETS, OIL SEALS, AND a-RINGS ...... 1-2 BEARINGS AND OIL SEALS ....................... 1-2 CIRCLlPS ...................................................... 1-2 SPECIAL TOOLS ............................................... 1-3 FOR TUNE UP .............................................. 1-3 FOR ENGINE SERVICE ................................ 1-4 FOR POWER TRAIN SERVICE .................... 1-4 FOR ELECTRICAL SERVICE ........................ 1-6


MACHINE IDENTIFICATION

----

I~EF~ I~I

GENERAL INFORMATION MACHINE IDENTIFICATION FRAME SERIAL NUMBER The frame serial number CD is located on the right-hand side of the frame (just below the front of the seat).

ENGINE SERIAL NUMBER (Primary I.D.l The engine serial number CD is located on the right-hand side of the crankcase. NOTE: _________________________ The first three digits of these numbers are for model identification; the remaining digits are the unit production number. Starting Serial Number VT480R ........................ 88T-000101

NOTE: ______________________ Designs and specifications are subject to change without notice.

1-1


IMPORTANT INFORMATION

I~Ej:~ IdtsI

IMPORTANT INFORMATION ALL REPLACEMENT PARTS 1. We recommend the use of Yamaha genuine parts for all replacements. Use oil and/or grease recommended by Yamaha for assembly and adjustment.

GASKETS, OIL SEALS, AND O-RINGS 1. All gaskets, seals, and O-rings should be replaced when an engine is overhauled. All gasket surfaces, oil seal lips, and O-rings must be cleaned. 2. Properly oil all mating parts and bearings during reassembly. Apply grease to the oil seal lips.

BEARINGS AND OIL SEALS 1. Install the bearing(s) CD and oil seal(s) <ID with their manufacturer's marks or numbers facing outward. (In other words, the stamped letters must be on the side exposed to view.) When installing oil seal(s), apply a light coating of light-weight lithium base grease to the seal lip(s). Oil the bearings liberally when installing.

300-002

Do not use compressed air to spin the bearings dry. This causes damage to the surface of the bearings.

300-003

CIRCLlPS 1. All circlips should be inspected carefully before reassembly. Always replace piston pin clips after one use. Replace misshapen circlips. When installing a circlip CD , make sure that the sharp edged corner <ID is positioned opposite the thrust ÂŽ it receives. See the sectional view. 300-001

@ Shaft

'-2


SPECIAL TOOLS

I~EF~ IJiMI

SPECIAL TOOLS Some special tools are necessary for complete accurate tune-up and assembly. Using the correct special tool will help prevent damage that can be caused by the use of improper tools or improvised techniques.

NOTE: ________________________ Be sure to use the correct part number when ordering the tool, since the part number differs according to the destination as shown below. The first part number is for Europe and the other number is for the U.S.A. and Canada. e.g. 90890-****, YU-****

FORTUNE UP 1. Vacuum Gauge @P/N YS-33275 ÂŽSealing Plug PIN YU-91035-3 (2 required) This tool is used for carburetor synchronization.

2. Sheave Gauge PIN 90890-01702, YS-91047 This gauge is used to measure sheave distance and for offset adjustment.

3. Dial Gauge P/N-90890-03097, YU-03097 This gauge is used for ignition timing adjustment.

1-3


SPECIAL TOOLS

I~~~I~I

FOR ENGINE SERVICE 1. Piston Pin Puller P/N-90890-01304, YU-01304 This tool is used to remove the piston pin.

2. Universal Rotor Holder P/N-90890-01235, YU-01235 This tool is used to hold the CDI magneto.

3. Rotor Puller P/N-90890-01362, YU-33270 This tool is used to remove the magneto rotor.

FOR POWER TRAIN SERVICE 1. Primary Sheave Holder P/N-90890-01701, YU-01880 This tool is used to hold the primary sheave.

2. Primary Sheave Puller (18 mm) P/N-90890-01898, YS-01882-A This tool is used for removing the primary

sheave.

1-4


SPECIAL TOOLS

I~EF~ lA!!I

3. Sheave Compressor P/N-90890-01712, YS-28891 This tool is used when disassembling and assembling the sheave.

4. Clutch Spider Separator P/N-90890-01711, YS-28890-B This tools are used when disassembling and assembling the primary sheave.

5. Clutch Separator Adapter P/N-90890-01740, YS-34480 This tool is used when disassembling and assembling the primary sheave.

6. Eccentric Bearing Installer P/N-90890-01721, YS-91 045 This tool is used when removing and installing the front axle.

1-5


SPECIAL TOOLS

Ig.EF~I~1

FOR ELECTRICAL SERVICE 1. Pocket Tester P/N-90890-03112, YU-03112 This instrument is necessary for checking the electrical components.

2. Electra Tester P/N-90890-03021, YU-33260 This instrument is used to check the electrical system.

1-6


_________~I ... I CHAPTER 2. PERIODIC INSPECTIONS AND ADJUSTMENTS INTRODUCTION ................................................ 2-1 PERIODIC MAINTENANCE TABLE ................... 2-1 ENGINE .............................................................. 2-3 SPARK PLUG ............................................... 2-3 FUEL FILTER INSPECTION ......................... 2-3 FUEL LINE INSPECTION ............................. 2-4 ENGINE OIL LINE INSPECTION ................. 2-4 THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK ........................................................ 2-5 THROTTLE CABLE FREE PLAY ADJUSTMENT ........................................... 2-5 CARBURETOR SYNCHRONIZATION ......... 2-6 ENGINE IDLE SPEED ADJUSTMENT ........ 2-8 EXHAUST SYSTEM .................................... 2-9 STARTER CABLE FREE PLAY ADJUSTMENT ........................................... 2-9 OIL PUMP .................................................. 2-10 COOLING FAN BELT ................................. 2-11 COOLING FAN BELT TENSION ADJUSTMENT ......................................... 2-12 SHEAVE DISTANCE AND OFFSET ADJUSTMENT ......................................... 2-13 POWER TRAIN ................................................. 2-16 DRIVE V-BELT ............................................ 2-16 ENGAGEMENT SPEED CHECK ................ 2-18 BRAKE PAD INSPECTION ........................ 2-18 BRAKE ADJUSTMENT .............................. 2-19 DRIVE CHAIN HOUSING OIL LEVEL INSPECTION ............................................ 2-19 DRIVE CHAIN TENSION ADJUSTMENT ......................................... 2-20 TRACK TENSION ADJUSTMENT ............ 2-21 SLIDE RUNNER INSPECTION .................. 2-23 CHASSIS .......................................................... 2-23 SKI/SKI RUNNER ....................................... 2-23 STEERING SYSTEM .................................. 2-23 SKI ADJUSTMENT .................................... 2-24 HANDLEBAR ADJUSTMENT ................... 2-25 LUBRICATION ........................................... 2-26

ELECTRICAL .................................................... 2-27 HEADLIGHT BULB REPLACEMENT ......... 2-27 HEADLIGHT BEAM ADJUSTMENT ......... 2-28 TAIL/BRAKE LIGHT BULB REPLACEMENT ....................................... 2-28 BATTERY INSPECTION ............................ 2-28 FUSE INSPECTION ................................... 2-30 TUNING ........................................................... 2-32 CARBURETOR TUNING ............................ 2-32 CLUTCH TUNING ...................................... 2-40 GEARING SELECTION .............................. 2-41 HIGH ALTITUDE TUNING ......................... 2-43 SLIDE RAIL SUSPENSION TURNING ...... 2-44


INTRODUCTION/IINSP PERIODIC MAINTENANCE TABLE

ADJ

I~ I ~

PERIODIC INSPECTIONS AND ADJUSTMENTS INTRODUCTION This chapter includes all ofthe information necessary to perform recommended inspections and adjustments. These preventive maintenance procedures, if followed, will ensure more reliable machine operation and a longer service life. In addition, the need for costly overhaul work will be greatly reduced. This information applies to machines already in service as well as new machines that are being prepared for sale. All service technicians should be familiar with this entire chapter.

PERIODIC MAINTENANCE TABLE

No.

Item

Remarks

Spark Plug

2

Engine Oil

3

Fuel

Check fuel level.

4

*Fuel Filter

Check condition. Replace if necessary.

S

*Fuel Line

Check fuel hose for cracks or damage. Replace if necessary.

6

*Oil Line

Check oil hose for cracks or damage. Replace if necessary.

Check oil level. *Air bleed the oil pump if necessary.

Check throttle lever operation. Carburetor

8

*Fan Belt

First Month or first 800 km (500 Mi) (40 hr)

Check condition, adjust the gap and clean. Replace if necessary.

1

7

Preoperation check (Daily)

• • •

• • • •

Whenever operating conditions (elevation/temperature) are changed.

*Adjust the jets.

• •

Check wear and damage. Replace if necessary. Adjust fan belt if necessary.

Manual Starter

Check operation and rope damage. *Replace if necessary.

10

Engine Stop Switch

Check operation *Repair if necessary.

11

Throttle Override System

Check operation. *Repair if necessary.

12

Throttle Lever

Check operation. *Repair if necessary.

13

*Exhaust System

14

*Decarbonization

9

Every Season or 3,200 km (2,000 Mi) (160 hr)

• • • •

Check for leakage. Retighten or replace gasket if necessary. More frequently if necessary.

15

Drive V-belt Guard

Check for cracks, bending or damage. *Replace if necessary.

16

Drive V-belt

Check wear and damage. Replace if necessary.

• •

• •

*: It is recommended that these items be serviced by a Yamaha dealer or other qualified mechanic. **: Perform after 1 Month or 50 Km (31 Mi) (2 hr) and every 1 Month or 400 Km (250 Mi).

2-1


PERIODIC MAINTENANCE TABLE

No.

Remarks

Item

17

Drive Track/Idler Wheels

18

Slide Runner

19

Brake/ Parking Brake

20

*Drive Chain Oil

21

*Drive Chain

22

Ski/Ski Runner

Check for deflection, wear and damage. *Adjust/replace if necessary. Check for wear and damage. *Replace if necessary. Check operation. *Adjust free play and/or replace pads if necessary.

First Month or first 800 km (500 Mi) (40 hr)

**.

• • •

Check oil level. Replace.

**.

Check for deflection. Adjust if necessary. Check for wear and damage. *Replace if necessary. Check operation.

23

Steering System

24

Lights

Check operation. Replace bulbs if necessary.

Battery

*Check specific gravity and breather pipe operation. Charge/Correct if necessary.

*Adjust toe-out if necessary.

Check fluid level. 25

Preoperation check (Daily)

Ir~ 1-.1

• • •

Adjust if necessary. *Primary Sheave

• • • •

• •

• • • • • • • • • •

Check engagement and shift speed. 26

Every Season or 3,200 km (2,000 Mi) (160hr)

Whenever operating elevation is changed.

Check for wear and damage. Replace if necessary. Lubricate with specified grease. Lubricate with specified grease.

27

*Secondary Sheave

28

*Steering Column Bearing

29

*Ski and Front Suspen- Lubricate with specified grease. sion

30

*Suspention Component

Lubricate with specified grease.

*Brake Cable End and Lever EndIThrottle Cable End

Lubricate with specified grease.

31

Adjust if necessary.

Whenever operating elevation is changed.

Lubricate with specified grease.

Check for cable damage. Replace if necessary.

32

Shroud Latches

Make sure the shroud latches are hooked.

33

Fittings/Fasteners

Check tightness. *Repair if necessary.

34

Service Tools/Spare Parts

Check proper placement.

• • •

*: It is recommended that these items be serviced by a Yamaha dealer or other qualified mechanic. **: Perform after 1 Month or 50 Km (31 Mi) and every month or 400 Km (250 Mi).

2-2


SPARK PLUG/FUEL FILTER INSPECTION

1r&.r 1_I

ENGINE SPARK PLUG 1. Remove: • Spark plug 2. Inspect: • Electrode CD Wear/Damage

~

Replace.

• Insulator color ® 3. Measure: • Plug gap@ Out of specification ~ Regap. Use a Wire Gauge of Feeler Gauge. Spark plug gap: 0.7 - 0.8 mm (0.028 - 0.032 in)

Clean the plug with a spark plug cleaner if necessary.

Standard spark plug: BR9ES (NGK) Before installing a spark plug, clean the gasket surface and plug surface.

4. Tighten: • Spark plug Spark plug: 28 Nm (2.8 m • kg, 20 ft • Ib)

(~Jl

NOTE: ________________________ Finger-tightenCDthe spark plug before torquing ® to specification.

377-004

FUEL FILTER INSPECTION 1. Remove: • Seat 2. Disconnect: • Tail/Brake light coupler

2-3


FUEL LINE INSPECTION/ENGINE OIL LINE INSPECTION 3. Remove: • Spring bands • Cap® • Fuel filter ®

Ir~ 1.1

CD

4. Inspect: • Fuel filter CD Contamination

---+

Replace.

Recommended replacement interval: Every season

FUEL LINE INSPECTION 1. Inspect: • Fuel hoses • Fuel delivery hoses Cracks/Damage ---+ Replace.

ENGINE OIL LINE INSPECTION 1. Inspect: • Oil hoses CD • Oil delivery hoses ® Cracks/Damage ---+ Replace.

2-4


THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK/IINSP I ~ I THROTTLE CABLE FREE PLAY ADJUSTMENT. ~

ADJ .

.

THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK

AWARNING When checking T.O.R.S.: • Be sure the parking brake is applied. • Be sure the throttle lever moves smoothly . • Do not run the engine up to clutch engagement rpm. Otherwise, the machine could start moving forward unexpectedly, which could cause an accident.

1. Start the engine.

NOTE: _ _ _ _ _ _ _ _ _ _ __ Refer to STARTING THE ENGINE.

2. Hold the pivot point ofthe throttle lever away from the throttle switch CD . 3. Press <ID the throttle lever gradually. The engine should stop immediately. If the engine does not stop T.O.R.S. (See page 7-31, 32)

->

Replace the

THROTTLE CABLE FREE PLAY ADJUSTMENT NOTE: ________________ Before adjusting the throttle cable free play, the engine idle speed should be adjusted.

1. Measure: • Throttle cable free play @ Out of specification --. Adjust.

)

Throttle cable free play: 1.0 - 2.0 mm (0.04 - 0.08 in)

2-5


CARBURETOR SYNCHRONIZATION

IrCf 1.1

2.Adjust: • Throttle cable free play Adjustment steps: • Open the shroud. Refer to the "SHROUD OPENING" section. • Loosen the locknut CD . • Turn the adjuster CV in or out until the specified free play is obtained. Turning in Turning out

Free play is increased. Free play is decreased.

• Tighten the locknut. • Reset the shroud.

CARBURETOR SYNCHRONIZATION 1. Remove: • Air chamber

CD

2. Plug the holes CD in the carburetor joint with sealing bulbs (See page 1-3).

NOTE: _ _ _ _ _ _ _ _ _ _ _ __ Be sure the pieces are securely installed.

3. Remove: • Rubber caps (vacuum plug)

2-6

CV


CARBURETOR SYNCHRONIZATION

Irgj Itill

4. Attach: • Vacuum gauge CD (to vacuum plugs on carburetor)

left and

right

Adaptor YU-91 035-3

Vacuum gauge: YS-33275

5. Start the engine and let it warm up.

AWARNING Do not move the throttle enough to reach the following engagement speed. The snowmobile could accidentally start to move forward. Engine revolutions: 3,000 r/min

6. Adjust: • Carburetor synchronization

Adjustment steps: • Synchronize the carburetor (left) with the carburetor (right) by turning synchronizing screw CD until both gauges show the same reading . • Race the engine, two or three times (for less than a second each time), and check the synchronization again.

7. Remove: • Vacuum gauge • Sealing plugs CD

2-7


ENGINE IDLE SPEED ADJUSTMENT

Ir8f I§ill

8. Inspect: • Rubber caps (vacuum plug) CD Wear/Damage --> Replace. • Air chamber ® Cracks/Damage . ~ Replace. 9. Install: • When reassembling the air chamber, reverse the removal steps. • Check the idle speed, adjust if necessary.

ENGINE IDLE SPEED ADJUSTMENT NOTE: ________________________ Be sure the carburetor synchronization has been set before making the idle speed adjustment. 1. Adjust: • Engine idle speed

Adjustment steps: • Turn in the pilot screws CD on the left and right carburetor until they are lightly seated. • Turn out the pilot screws for the specified number of turns. Pilot screw: 1-1/2 counterclockwise turns • Start the engine and let it warm up. • Turn the throttle stop screw ® until the idle speed is in the specified range. Use the Inductive tachometer. Turning in Turning out

Ifb ~

Idle speed becomes higher. Idle speed becomes lower.

Inductive tachometer: PIN. 90890-08036, VU-08036 Engine idle speed: 1,500 - 1,700 rlmin

• Turnthe pilotscrewsCDin orout by increments of 1/8 turn to achieve the highest speed with just the pilot screws. • Once again, turn the throttle stop screw to obtain the specified idle speed.

®

NOTE: After adjusting the engine idle speed, the throttle cable free play should be adjusted.

2-8


EXHAUST SYSTEM/ STARTER CABLE FREE PLAY ADJUSTMENT

IINSP I~ I ADJ •

EXHAUST SYSTEM 1. Inspect: • Exhaust pipe gasket(s) CD Damage -7 Replace. Exhaust gas leakage --> Repair. Tighten the nuts • Joint pipe exhaust gas leakage ® Tension spring ® -7 Replace.

Muffler nut: 20 Nm (2,0 m • kg, 14.5 ft· Ib)

STARTER CABLE FREE PLAY ADJUSTMENT 1. Pull the outer tube of starter cable 2. Measure: • Starter cable free play ® Out of specification-> Adjust. 1-'+---+

®

CD upward.

Free play ®: 0.5 - 1.5 mm (0.02 - 0.06 in)

3. Adjust: • Starter cable free play Adjustment steps: • Loosen the locknut CD . • Turn the adjuster®in or out until the specified free play is obtained. Turning in Turning out

Free play is increased. Free play is decreased.

• Tighten the locknut and push in the adjuster cover.

2-9


O'LPUMpl~ I_I OIL PUMP • Air Bleeding

The oil pump and delivery line must be bled on the following occasions: • When any portion of the oil system has been disconnected. • When the machine has been turned on its side. • Whenever the oil tank has been run empty. • Before predelivery. 1. Remove: • Drive V-belt

• Secondary sheave assembly • Carburetor assembly (See page 6-4)

2. Bleeding the air • Bleed screw CD (with gasket) Loosen the bleed screw at the oil pump. Oil should begin to flow through the line. Keep the bleed screw open until all air has left the oil line and oil pump. Tighten the bleed screw. 3. Install: • Carburetors • Secondary sheave assembly • Drive V-belt/guard Reverse removal steps 4.Adjust • Oil pump cable free play Adjustment steps: • Loosen the locknut CD . • Turn the adjuster®in or out until the specified free play is obtained.

~

Free play ®: 21 - 23 mm (0.83 - 0.91 in)

Turning in

Free play is increased.

Turning out

Free play is decreased.

• Tighten the locknut and push in the adjuster cover.

2-10


COOLING FAN BELT

Irgr Iill

COOLING FAN BELT 1. Remove: • Air duct (cooling fan) CD • Cover (cooling fan) ®

2. Inspect: • Fan belt Wear/Cracks/Damage

~

Replace.

3. Remove: • Recoil starter assembly

4. Remove: • Drive pulley (fan belt)

CD

CD

NOTE: __________________________ Use the universal rotor holder®to hold the drive pulley (fan belt). Universal rotor holder: 90880-01235, VU-01235 • Fan belt

®

5. Install: • Fan belt ® • Drive pulley (fan belt)

CD

NOTE: ________________________ Hold the drive pulley (fan belt) using the universal rotor holder ® to tighten the bolts.

2-11


COOLING FAN BELT TENSION ADJUSTMENT

Imr 1.1

COOLING FAN BELT TENSION ADJUSTMENT

1.Adjust: • Fan belt deflection ® Pushed at belt center by a force of 4 - 6 kg (8.8 - 13.2 Ib). Out of specification -> Adjust. Fan belt deflection: 8 mm (0.31 in)1 4 - 6 kg, (8.8 - 13.2 Ib) 2. Adjust: • Fan belt deflection. Adjustment steps: • Remove the recoil starter assembly, drive pulley and fan belt. • Refer to the "COWLING FAN BELT INSPECTION" section. • Remove the driven pulley (outer half) <D and shim(s)® . • Adjust the drive belt tension by adding or removing a shim(s) ® .

NOTE: Install the removed shim (s) on the outside of the driven pulley. Do not dispose of the removed shim (s). Adding shim Removing shim

Belt tension decreases. Belt tension increases. Shim size

Part Number 90214-17017 90214-17018

Thickness 0.5 mm (0.02 in) 1.0 mm (0.04in)

• Tighten the driven pulley nut

!~

®.

Nut (driven pulley): 42 Nm (4.2 m • kg, 30.3 ft • Ib)

• Install the fan belt @ and drive pulley

I~

2-12

CID .

Bolt (drive pulley-fan belt): 23 Nm (2.3 m • kg, 16.6 ft· Ib)


SHEAVE DISTANCE AND OFFSET ADJUSTMENT

Ir8~ IQ I

• Recheck the fan belt deflection. If out of the specification, repeat the above steps. If within the specification, install the recoil starter assembly ® . Bolt (recoil starter assembly): 6 Nm (0.6 m • kg, 4.3 ft • Ib)

3. Install: • Cover (cooling fan) • Air duct (cooling fan) Reverse removal steps

SHEAVE DISTANCE AND OFFSET ADJUSTMENT 1. Remove: • Drive V-belt guard • Drive V-belt

2. Measure: • Sheave distance ® Use the Sheave Gauge. Out of specification > Adjust. Sheave gauge: 90890-01702, VS-91047 Sheave distance ® : 267 - 270 mm (10.5 - 10.6 in) 3. Adjust: • Sheave distance

®

Adjustment steps: • Check the engine mounting bracket, dampers and frame for bending, cracks and weathering. Replace as needed. • Loosen the engine mounting nuts CD , ® .

2-13


SHEAVE DISTANCE AND OFFSET ADJUSTMENT'

~8r

,.,

• Adjust the position of the engine so that the sheave distance is within the specification . • Tighten the engine mounting nuts CD, ®. Mounting nut: 40 Nm (4.0 m . kg, 29 ft . Ib)

4. Measure: • Sheave offset QV Use the Sheave Gauge. Out of specification --+ Adjust. Sheave offset QV : 10.5 - 12.5 mm (0.41 - 0.49 in) Sheave gauge: YS-91047 5. Adjust: • Sheave offset

QV

Adjustment steps: • Apply the brake to lock the secondary sheave. • Remove the bolt CD (secondary sheave) washer ® and secondary sheave ® . • Adjust the sheave offset by adding or removing a shim (s) @ . Adding shim Removing shim

Offset is increased. Offset is decreased. Shim size

Part Number 90201-252F1 90201-25527 90201-25526

Thickness 0.5 mm (0.02 in) 1.0 mm (0.04 in) 2.0 mm (0.08 in)

• Install the secondary sheave and bolt (secondary sheave).

Bolt (secondary sheave): 60 Nm (6.0 m • kg, 43 ft • Ib)

• Recheck the sheave offset. If out of specification, repeat the above steps.

2-14


SHEAVE DISTANCE AND OFFSET ADJUSTMENT

Irgj IQ I

NOTE: _ _ _ _ _ _ _ _ _ _ __

When adjusting the sheave offset, the secondary sheave free play (clearance) should also be adjusted.

6. Measure: • Secondary sheave free play (clearance) Use a feeler gauge. Out of specification -> Adjust. , .#'.'(

~ ............ . .',

L/ '

'.

~

©.

Secondary sheave free play (clearance) © : I--;W 0.5 - 1.0 mm (0.02 - 0.04 in)

7.Adjust: • Secondary sheave free play (clearance) Adjustment steps: • Apply the brake to lock the secondary sheave . • Remove the bolt CD (secondary sheave) and washer

®.

• Adjust the secondary sheave free play (clearance) by adding or removing a shim(s)

@. Adding shim

Free play is decreased.

Removing shim

Free play is increased. Shim size

Part Number 90201-222FO 90201-225A4

Thickness 0.5 mm (0.02 in) 1.0 mm (0.04 in)

• Install the washer bolt (secondary sheave) and tighten the bolt.

Bolt (secondary sheave): 60 Nm (6.0 m·kg, 43 ft·lb)

• Recheck the secondary sheave free play (clearance). If out of specification, repeat the above steps.

2-15


2mm (O.079mm)

1

2

POWER TRAIN DRIVE V-BELT

AWARNING • Be sure there is a 2.0 mm (0.79 in) gap between the secondary sheaves (fixed CD and sliding ® ) when installing a NEW belt. If there is no gap, the clutch engagement speed will be reduced. The machine may move unexpectedly when the engine is started . • The spacer of the secondary sheave should be adjusted. (See page 4-14)

~I

To ensure proper clutch performance, the spacers in the secondary clutch must be repositioned as the V-belt wears.

CD

Number of Shims

A

31.6 mm (1.24 in) or more

2 spacers

B

30.6 mm (1.20 in)

1 spacer

C

29.6 mm (1.17 in)

No spacer

28 mm (1.10 in) or less

Replace the V-belt

V-belt Width

~II

1. Remove: • Side cowling (left) • Bolt (drive V-belt guard) • Drive V-belt guard ®

CD

NOTE: _________________________ Press the holding pin @ all the way in until it releases from the hook@, then reverse it 90· and pull it out.

2. Remove: • Drive V-belt

NOTE: ________________________ Apply the parking brake before replacement.

2-16


DRIVE V-BELT

Irgf I'it I

Removal steps: • Rotate the secondary sliding sheave clockwiseCDand push CVit so that it separates from the fixed sheave. • Pull the belt up over the secondary fixed sheave. • Remove the belt ® from the secondary and primary sheaves.

3. Inspect: • Drive V-belt Crack/Wear/Damage ---> Replace. Oil or grease on the V-belt ---> Check the primary and secondary sheaves.

4. Inspect: • Primary sheave CD • Secondary sheave CV Oil or grease on the primary and secondary sheaves ---> Remove the oil or grease using a rag soaked in lacquer, thinner or solvent. Check the primary and secondary sheaves.

5. Measure: • Drive V-belt length ® Out of specification -7 Replace.

®

Drive V-belt length: 1,099 mm (43.3 in)

2-17


ENGAGEMENT SPEED CHECK/BRAKE PAD INSPECTION

I~8r IMI

6. Install • Drive V-belt Installation steps: • Install the new belt over the primary sheave. • Rotate the secondary sliding sheave clockwiseCDand push ®it so that it separates from the fixed sheave. • Install the belt ® between the secondary sliding and fixed sheaves. • Install the drive V-belt guard.

ENGAGEMENT SPEED CHECK 1. Place the machine on a level place in hard packed snow. 2. Check: • Clutch engagement speed

Checking steps: • Start the engine, and open the throttle lever gradually . • Check the engine speed when the machine starts moving forward. Out of specification- -> Adjust the primary sheave. (See page 4-4)

C)

Engagement speed: Approx. 3300 r/min

BRAKE PAD INSPECTION 1. Apply the brake lever. 2. Measure: • Brake pad thickness ® Out of specification -> Replace brake pad as a set. (See page 4-35)

~ 2-18

Wear limit: 9.5 mm 10.37 1nl


BRAKE ADJUSTMENT/IINSP I DRIVE CHAIN HOUSING OIL LEVEL INSPECTION

~

ADJ •

I

BRAKE ADJUSTMENT NOTE: _________________________ Adjust brake every 40 hours of operation, or whenever the brake lever becomes loose during operation.

1. Measure: • Distance "L" Out of specification

--+

Adjust.

Distance "l" 44 - 47.5 mm (1.73 - 1.87 in)

2. Adjust: • Distance "L" Adjustment steps:

• Loosen the locknut CD . • Turn the adjuster CV in or out until specified distance is obtained. Turning in Turning out

Distance "l" is increased. Distance "l" is decreased.

• Tighten the locknut

CD .

DRIVE CHAIN HOUSING OIL LEVEL INSPECTION 1. Place the machine on a level place and open the shroud.

NOTE: _________________________ Be sure the machine is positioned straight up when inspecting the oil level.

2-19


DRIVE CHAIN TENSION ADJUSTMENT

It'8f Ig, I

1. Check • Oil level CDUpper level ®Lower level

NOTE: __________________________ Rest the filler cap on the case threads when measuring oil level. Do not screw in the filler cap.

2. Oil replacement • Warm up the engine for several minutes. • Place a receptacle under the chain case. • Remove the drain plug ®

Be sure no foreign material enters the chain housing case.

Recommended oil: Gear oil API GL-3 SAE #75 or #SO Oil capacity: 250 cm 3 (S.S Imp OZ, S.5 US oz)

DRIVE CHAIN TENSION ADJUSTMENT 1. Adjust • Drive chain adjustment Adjustment steps: • Loosen the locknut CD • Shift the shift lever to "FORWARD" position • Turn the secondary sheave one turn counterclockwise. • Turn in the adjusting bolt ® , until it lightly the contacts tensioner, then turn in the adjusting bolt ® 1/2 to 2/3 turn more. • Tighten the locknut CD.

2-20


TRACK TENSION ADJUSTMENTI

rgr 1.1

TRACK TENSION ADJUSTMENT

AWARNING A broken track, track fittings, or debris thrown upward by the track could be dangerous to the operator or bystanders. Observe the following pre-cautions. 1 . Do not allow anyone to stand directly behind the machine when starting forward. 2. When the engine is running and the track is engaged with the machine on its side, do not allow anyone to stand behind or on the track side of the machine. The operator must stay near on the seat front. 3. Never lift the rear of the machine to allow the track to turn while the engine is running. Stop the engine and prop up the rear with a suitable stand. Never stand behind a machine when the track is spinning. 4. Never install studs (cleats) any closer than three inches from the edge of the track. 5. Replace any track that is damaged to the depth where the fabric reinforcement material is visible. Inspect the track condition frequently.

1. Lift the rear of the machine onto a suitable stand to raise the track off the ground. 2. Turn the track several times by running the engine. 3. Place the machine with the right side facing down. Block the right side front suspension using a suitable block of wood as shown to prevent the machine from turning over.

@

25.4 mm(1.0 in)

@

114.3 mm(4.5 in)

4. Measure: â&#x20AC;˘ Track tension @ Pull at the track center window by a force of 10 kg (22 Ib) using a spring scale. Out of specification -> Adjust.

10 kg (22 Ib)

~I'~

Track tension: 25 - 30 mm/10 kg (0.98- 1.18 in/22Ib)

2-21


TRACK TENSION ADJUSTMENTI 5. Adjust: • Track deflection

mr I~ I

Adjustment steps:

• Lift the rear of the machine onto a suitable stand to raise the track off the ground. • Loosen the rear axle nut

CD .

NOTE: It is not necessary to remove the cotter pin

CV .

®

Start the engine and rotate the track one or two turns. Stop the engine. @ Check the track alignment with the slide runner CID. If the alignment is incorrect, turn the left and right adjusters @ , CID to adjust.

Track alignment

@ Left adjuster

CID Right adjuster ®Slide runner @ Track metal

©

®

® Shifted to

(j) Shifted to

right

left

Turn out

Turn in

Turn in

Turn out

@Track

(jJ) Gap

@ Forward

Adjust track deflection to the specified amount.

Track deflection

More than specified

@ Left adjuster

Turn in

Turn in

CID

Turn in

Turn out

Right adjuster

Less than specified

The adjusters should be turned an equal amount. • Recheck alignement and deflection. If necessary, repeat steps" ® " to "©" until proper adjustment is achieved. • Tighten the rear axle nut.

I® 2-22

Rear axle nut: 80 Nm (8.0 m • kg, 58 ft • Ib)


SLIDE RUNNER INSPECTION

Irgf IQ I

SLIDE RUNNER INSPECTION 1. Inspect: • Slide runner CD Cracks/Damage/Wear

~.~

Replace.

2. Measure: • Slide runner thickness CD Out of specification --+ Replace. (See page 4-45)

[e

~

Wear limit:

10 mm 10.40 ;"1

CHASSIS SKI/SKI RUNNER 1. Check: • Ski CD • Ski runner Cl) • Mounting bolt ® • Collar@ • Ski stopper ® Wear/Damage

~

Replace.

Ski runner wear limit 4.5 mm (0.18 in)

®:

819-002

STEERING SYSTEM Free play check 1. Check: • Steering system free play Push the handlebar up and down and back and forth. Turn the handlebar slightly to the right and left.

2-23


SKI ADJUSTMENTI

r~r I§Ill

SKI ADJUSTMENT 1. Place the machine on a level place and elevate the skis. 2. Hold the handlebars straight, and check to see that the skis are positioned at right angles to the handlebars. If they are not positioned correctly, adjust the skis. 3. Adjust: • Skis

Adjustment steps: • Open the shroud. • Remove the bolts (oil tank) CD . • Disconnect the oil hoses from the oil tank.

NOTE: _ _ _ _ _ _ _ _ _ __ Plug the oil hoses and oil tank so that oil does not run out. • Loosen the locknuts (steering relay rod) ® . • Direct the skis in parallel to the direction of movement. • With the skis thus, turn the relay rod ®either way to adjust the handlebars at right angles with respect to the direction of movement. o

Turning the relay The handlebars move rod in direction ® in direction © Turning the relay The handlebars move rod in direction @ in direction @) • Tighten the locknuts (steering relay rod) 2

Locknut (steering relay rod): 25 Nm (2.5 m . kg, 18 ft· Ib) LOCTITE®

Bolt (oil tank): 5 Nm (0.5 m • kg, 3.6 ft • Ib)

Bleed the air from the oil pump hose. (See page 2-10)

2-24

®.


SKI ADJUSTMENT/IINSP HANDLEBAR ADJUSTMENT

I~ I

ADJ •

4. Check: • Ski toe - out Direct the skis in parallel to the moving direction. Out of specification --> Adjust. Ski toe - out (® - ©): 0.0 - 15.0 mm (0.0 - 0.6 in) Ski stance@: 920 mm (36.2 in) 5. Adjust: • Ski toe - out Adjustment steps: • Open the shroud. • Loosen the locknuts (tie rod) CD . • Turn the relay rod CV in or out until the specified toe - out is obtained. • Tighten the locknuts (tie rod) CD .

Locknut (tie rod): 25 Nm (2.5 m . kg, 18 ft . Ib) LOCTITE@

• Close the shroud.

[KJ Left side [ID Right side

HANDLEBAR ADJUSTMENT 1. Adjust: • Handlebar position Adjustment steps: • Remove the handlebar covers (rear) CD . • Loosen the bolts (handlebar holder) CV . • Adjust the handlebar position by moving the handlebar forward and backward. • Tighten the bolts (handlebar holder) CV to specification so that the front clearance "a" is smaller than rear clearance "b".

I® 2-25

Bolt (handlebar holder): 15 Nm (1.5 m· kg, 11 ft ·Ib)


BRAKE LEVER AND BRAKE CABLE END LUBRICATION

~ "a"L~ ~CDT

"a"

<

r-----'

Irgr I _I

• Be sure the small gap CD side of the holder faces forward.

,

~ "b"

• Install the handlebar covers (rear) CD

.

"b"

LUBRICATION Brake lever 1. Lubricate the brake lever pivot and brake cable end.

~ Esso Beacon 325 Grease. AWARNING Do not apply grease between the outer cable and inner cable.

2-26


HEADLIGHT BULB REPLACEMENT

Ir8j I~ I

ELECTRICAL HEADLIGHT BULB REPLACEMENT 1. Remove: • Cover CD (bulb holder) • Bulb holder (ID • Bulb (defective) ®

NOTE: ________________________ While pushing the bulb holder counterclockwise.

(ID , turn it

AWARNING Keep flammable products (and your hands) away from the bulb while it is on, it will be hot. Do not touch the bulb until it cools down.

2. Install: • Bulb (new)

Avoid touching the glass part of the bulb. Keep it free from oil; otherwise, the transparency of the glass, life of the bulb and flux will be adversely affected. If oil gets on the bulb, thoroughly clean it with a cloth moistened with alcohol or lacquer thinner. 3. Install: • Bulb holder

CD

NOTE: __________________________ • Install the bulb holder so that the "TOP"mark@ faces upward . • While pushing the bulb holder CD , turn it clockwise.

4. Install: • Cover (bulb holder)

CD

NOTE: _________________________ Install the bulb holder cover so that the "TOP" mark @ faces upward. 5.Adjust: • Headlight beam (See page 2-28)

2-27


HEADLIGHT BEAM ADJUSTMENT /IINSP TAIL/BRAKE LIGHT BULB REPLACEMENT

ADJ

I~ I ~

HEADLIGHT BEAM ADJUSTMENT 1. Place the machine on a level place. 2. Inspect: • Headlight beam direction The high beam should be directed downward at an angle of 1/2 to the horizontal line. If not, adjust the direction. 0

L

3.0 m (10 ft)

7.6 m (25 ft)

H

26 mm (1.0 in)

66 mm (2.6 in)

3. Adjust: • Headlight beam direction Adjust the headlight beam by tightening or loosening the adjusters CD .

TAIL/BRAKE LIGHT BULB REPLACEMENT 1. Remove: • Tail/Brake light lens

CD

2. Remove: • Bulb (defective)

CD

NOTE: _ _ _ _ _ _ _ _ _ _ __ While pushing the bulb clockwise.

CD , turn

BATTERV INSPECTION 1. Remove: • Protector plate (battery) • Battery

2-28

CD

it counter


BATIERV INSPECTION

Ir8f IQ I

2. Inspect: • Battery fluid level Fluid level should be between upper CD and lower CV level marks. Incorrect --+ Refill.

Refill with distilled water only; tap water contains minerals harmful to a battery.

3. Check: • Specific gravity Less than 1.280

----1>

--+

Recharge battery.

Charging current: 1.4 amps/10 hrs Specific gravity: 1.280 at 20°C (68°F) 367 003

Replace the battery if: • Battery voltage will not rise to a specific value or if bubbles fail to rise even after many hours of charging. • Sulfation of one or more cells occurs, as indicated by the plates turning white, or if an accumulation of material exists in the bottom of the cell. • Specific gravity readings after a long, slow charge indicate one cell to be lower than the rest. • Warpage or buckling of plates or insulators is evident.

Always charge a new battery before using it to ensure maximum performance.

4. Install: • Fit the breather hose CD to the battery CV . • Install the battery in the battery box. • Fit the battery plate ® bracket CID and heater plateQ)to the battery the nuts@and screws

--?:':I---®

:oiiiiII--~

@.

2-29


BATTERY INSPECTION/FUSE INSPECTION NOTE: _________________________ • Make sure the main switch is turned off. • Be sure to tighten the screws@aftertightening the nuts @ . • First, connectthe positive cable@, and then the negative cable ® to the battery as shown.

AWARNING Battery electrolyte is dangerous; it contains sulfuric acid and therefore is poisonous and highly caustic. Always follow these preventive measures: • Avoid bodily contact with electrolyte as it can cause severe burns or permanent eye injury. • Wear protective eye gear when handling or working near batteries. Antidote (EXTERNAL):

367-009

• SKIN - Flush with water. • EYES - Flush with water for 15 minutes and get immediate medical attention. Antidote (INTERNAL): • Drink large quantities of water or milk, and follow with milk of magnesia, beaten egg, or vegetable oil. Get immediate medical attention. Batteries also generate explosive hydrogen gas, therefore you should always follow these preventive measures: • Charge batteries in a well-ventilated area. • Keep batteries away from fire, sparks, or open flames (e.g., welding equipment, lighted cigarettes, etc.) • DO NOT SMOKE when charging or handling batteries. KEEP BATTERIES AND ELECTROLYTE OUT OF REACH OF CHILDREN.

FUSE INSPECTION 1. Remove: • Fuse CD • Spare fuse

2-30

®


FUSE INSPECTION 2. Inspect: • Fuse

~

Inspection: • Connect a pocket tester to the fuse and check it for continuity.

~@±

NOTE:

J.....

Set the tester selector to

~

"n x

1" position.

Pocket tester: YU-03112

• If the tester indicates It must be replaced.

00

the fuse is blown.

3. Replace: • Blown fuse Replacement steps: • Turn off the ignition and the circuit. • Install a new fuse of proper amperage. • Turn on the switches to verify operation of the electrical device. • Ifthe fuse blows again immediately, check the circuit in question.

NOTE: _______________________ Install new fuses of proper amperage. Description

Amperage

Quantity

Main

10A

1

Spare

10A

1

AWARNING Do not use fuses of higher amperage rating than that which is recommended. Extensive electrical system damage and fire could result from the substitution of a fuse of improper amperage.

2-31


CARBURETOR TUNING

I~r Itill

TUNING CARBURETOR TUNING The carburetor is set at the factory to run at temperatures of -20 (32°F - -4°F) at sea level. If the machine has to be operated under conditions other than those specified above, the carburetor must be reset as required. Special care should be taken when setting the carburetor so that the piston will not be damaged or seized.

ooe -

oe

In this model, the engine oil is mixed with the fuel just before the fuel enters the intake manifold, so it is not always possible to supply the optimum mixture depending on the throttle opening.Therefore, after the carburetor is tuned up or maintained, or after the float chamber is removed for cleaning or jet replacement, be sure to idle the engine for about three minutes in order to avoid engine trouble.

Before tuning the carburetor, make sure that the conditions for the following items are correct. • Engine idle speed adjustment • Throttle cable free play adjustment • Carburetor synchronization • Starter cable adjustment • Oil pump cable free play adjustment Carburetor Tuning Data 1. Standard specifications

2-32

Model

B38-32 x 2

Manufacturer

MIKUNI

1.0. Mark

(L) 8V003 (R)80L03

Main jet (M.J.)

#143.8

Pilot jet (P.J.)

#95

Pilot air jet (P.A.J.)

00.5

Pilot screw (P.S.)

1-1/2 turns out

Throttle valve (Th.V)

#120

Float height

9.5 -13.5 mm (0.37 - 0.53 in)

Idle speed

1,500 - 1,700 r/min


CARBURETOR TUNING

Ir8~ IQ I

Middle-Range and High Speed Tuning No adjustment is normally required, but adjustments may sometimes be necessary, depending on temperatures and/or altitude. Middle-range speed and high speed tuning (from 1/4 to full-throttle) can be done by adjusting the main jet.

The engine should never be run without the air intake silencer and air chamber installed; severe engine damage may result.

1. Start the engine and operate the machine under normal condition to make sure the engine operates smoothly. Then stop the engine. 2.Remove: â&#x20AC;˘ Spark plugs.

3. Check: â&#x20AC;˘ Spark plug insulator CD color A medium to lighttan color indicates normal conditions. Distinctly different color.. Replace main jet. 4. The main jet should be adjusted on the basis of the following "Main jet selection chart".

NOTE: __________________________ By checking the condition of the spark plugs currently being used, it is easy to get some idea of the engine condition and catch areas that may cause problems before they are too far advanced.

2-33


CARBURETOR TUNING

Ir~r IQ I

5. High altitude tuning A guide to the main jet setting according to variations in elevation and temperature. CARBURETOR SEnlNG CHART ELEVATION

o to 300 It

TEMP

- 300C - 200C -10°C -22°F - 4°F 14°F

OnC 32°F

---MJ #150 - - - ~ MJ #143.8 (STD) MJ#152.5} 0-2000 FT. DRIVE LINE SETTINGS

}

2OOQ.6OO()

FT. DRIVE LINE SETTINGS

} ABOVE 6000 FT. DRIVE LINE SETTINGS

MJ

= Main Jet

PS

= Idle Mixture Screw

-~

I

CD Main jet (M.J.) ® Main jet holder

2-34


CARBURETOR TUNING 6. Fuel flow chart:

I

Total fuel flow

t ....

1/4

1/2

Throttle opening

3/4

A guide to the fuel flow rate according to the throttle opening.

If the air intake silencer and air chamber are removed from the carburetors, the change in pressure in the intake will create a lean mixture that could result in severe engine damage. Removal of the air intake silencer and the air chamber do not improve performance characteristics. They must be secured to the carburetor during tuning and adjustment, and must always be in place when the engine is operated. Examine the intake silencer and air chamber regularly for cleanliness and freedom from obstruction.

$

1/8

re! I'ill I

I

1/1

--+

ÂŽ

High speed tuning range @Mid-range speed tuning range Low speed tuning range

Š

2-35


CARBURETOR TUNING NOTE: _________________________ • The smaller the main jet size, the leaner the mixture. • During warm weather or in high altitudes, a smaller main jet should be used. • puring periods of excessively cold weather, a larger main jet should be used. • Too lean a mixture can cause overheating and possible engine failure. • Too rich a mixture can cause poor performance and excessive carbon formation with accompanying shorter spark plug life.

Standard Main Jet: #143.8

AWARNING Never remove the main jet cover while the engine is hot. Fuel will flow out of the float chamber, and this could ignite and cause damage to the snowmobile and possible injury to the mechanic. Place a rag under the carburetor so fuel does not spread. Place the main jet cover in a clean place. Keep it away from fire. After assembling the carburetor, firmly tighten the intake silencer joint clamps and intake manifold clamps. Make sure the throttle cable is in place, and that it operates smoothly. "Clean the carburetor, and allow it to dry."

Main jet selection chart Spark plug color

Check up

Remedy

Light tan or gray.

Carburetor is tuned properly.

Dry black or fluffy deposits.

Mixture is too rich.

Replace main jet with the next smaller size.

White or light gray.

Mixture is too lean.

Replace main jet with the next larger size.

White or gray insulator with small black or gray brown spots and with a bluish-burnt appearance of electrodes.

Due to too lean a mixture, the piston is damaged or seized.

Replace the piston and spark plug. Tune the carburetor again, starting with lowspeed tuning.

Due to too lean a mixture, the spark plug melts.

Check the piston for holes or seizure. Check the cooling system, gasoline octane rating and ignition timing. After replacing the spark plug with a colder type, tune the carburetor again starting with low-speed tuning.

Melted electrodes and possibly blistered insulator. Metallic deposits on insulator.

2-36


CARBURETOR TUNING 7. Replace: • Main jet

,o

Replacement steps: • Remove the carburetor assembly. Refer to the "CARBURETOR - REMOVAL" section in the CHAPTER 6. • Place a rag under the carburetor. • Drain the fuel from the float chamber by removing the drain plug CD and gasket CV . • Replace the main jet@tothe proper sized jet. • Check the gasket CV of the drain plug. If damaged, replace it. • When reassembling, reverse the above steps. • Recheck the engine (spark plug insulator color) condition. If the engine shows poor performance and spark plug color is bad, perform the above steps again.

3

2-37


CARBURETOR TUNING

I~ IMI

Troubleshooting Trouble Hard starting

Insufficient fuel

(Related troubles) • Poor performance at low speeds • Poor acceleration • Slow response to throttle • Engine tends to stall

Add gasoline

Adjustment ~

....

; J

Excessive use of starter Clean spark plug (Excessively opened choke)

Return starter level to its seated position.

Fuel passage is clogged Clean or frozen

Parts other than air carburetor. • Clogged fuel tank air vent, clogged fuel fifter, or clogged fuel passage Carburetor • Clogged or frozen airvent, or clogged valve. • If water collects in float chamber, clean. (Also check for ice)

Overflow Poor idling

Remedy

Check point

Correct

Improper idling speed adjustment Adjust idling speed • Pilot screw

• Throttle stop screw

Adjust

Damaged pilot screw

Replace pilot screw

Clogged bypass hole

Clean

Clogged or loose pilot Clean and retighten jet

Bottom the pilot screw lightly, and back it out to specification. Start the engine and turn pilot screw in and out 1/4 turn each time. When the engine runs faster, back out throttle stop screw so the engine idles at specified speed. Tightened too much - Engine speed is higher. Backed out too much Engine does not idle.

Remove pilot jet, and blow it out with compressed air.

Air leaking into carbure- Retighten bend screw tor joint Defective starter valve Clean or replace seat Overflow Poor performance at mid-range speeds (Related troubles) • Momentary slow response to throttle • Poor acceleration Poor performance at normal speeds (Related troubles) • Excess fuel consumption • Poor acceleration

Correct

Clogged or loose pilot Clean and retighten jet

Lean mixtures Clogged air vent

Overhaul carburetor Remove the air vent pipe, and Clean clean.

Clogged or loose main Clean and retighten jet Overflow

Remove pilot jet, and blow it out with compressed air.

Check float and float valve and clean

2-38

Remove main jet, and blow it out with compressed air.


CARBURETOR TUNING Remedy Check point Fully close valve Poor performance at Starter valve is left open high speeds (Related troubles) Clogged air vent Remove and clean • Power loss Clogged or loose main Clean and retighten • Poor acceleration jet Trouble

Clogged fuel pipe

Clean or replace

Dirty fuel tank

Clean fuel tank

Air leaking into fuel line

Check joint and retighten

Low fuel formance

I~j I~ I Adjustment

Return starter lever to its home position. Remove main jet and clean with compressed air, then install.

pump per- Repair pump or replace

Clogged fuel filter Clogged intake Abnormal combus- Lean mixtures tion (Mainly backfire) Dirty carburetor

Replace Check for and removeice Clean carburetor and adjust Clean carburetor

Dirty or clogged fuel Clean or replace fuel pipe pipe Overflow (Related troubles) • Power idling • Poor performance at low, mid-range, and high speeds • Excessive fuel consumption • Hard starting • Power loss • Poor acceleration

Clogged air vent

Clean

Clogged float valve

Disassemble clean

and Clean while taking care not to scratch valve seat.

Scratched or unevenly Clean or replace float Valve seat is press-fitted to worn float valve or valve and valve seat body. valve seat The body must be replaced if seat is damaged. Broken float

Replace float

Incorrect float level

If not within the range, specified check the following parts and replace any defective part. Replace float assembly. • Replace float • Replace arm pin • Replace float

• Worn float tang • Worn pin • Deformed float arm

2-39


CLUTCH TUNING

Ir8! IQ I

CLUTCH TUNING The clutch may require tuning depending upon the area of operation and desired handling characteristics. The clutch can be tuned by changing engagement and shifting speed. Clutch engagement speed is defined as the engine speed where the machine first begins to move from a complete stop. Shifting speed is the engine speed when the machine passes a point 200 - 300 m (650 - 1,000 ft) from the starting position after the machine has been started at full-throttle from a dead stop. Normally, when a machine reaches shift speed, the vehicle speed increases but the engine speed remains nearly constant. Under unfavorable conditions (wet snow, icy snow, hills, or rough terrain) however, engine speed may decrease after the shifting speed has been reached.

Engine speed

t

Engine speed

t

Good condition

Bad condition Clutch shifting speed

Clutch shifting speed

Clutch engagement speed

Clutch engagement speed -

Travelled distance

-

Starting position

Starting position

200 - 300 mm (650 - 1, 00 ft)

200 - 300 mm (650 - 1,000 ft)

2-40

Travelled distance


GEARING SELECTION

1

r~ 1Q.I

High Altitude Tuning High altitude specifications should be applied for operation at an altitude of more than 600 meters (2,000 ft).

Clutch Setting Data 2000 ft/600 m (STD) 2000 ft - 6000 ft (HA) 6000 ft/1800 m (HA)

Item Engagement speed

Approx. 3300 rpm

~

Shifting speed

Approx. 6850 rpm

f-

f-

O'ty

3 pcs

f-

f-

Part No.

8VO-W176A-OO

85L-W176A-00

f-

Part No.

90501-50543

90501-55559

90501-554G6

Preload

20 kg-1.4 kg/mm

17.4 kg

27.5 kg

Spring Rate

1.4 kg/mm

3.0 kg/mm

f-

Weight

Primary spring

Secondary spring

Approx. 3400 rpm

Color

Green-Green

Blue

Yellow-Yellow

Part No.

90508-50571

f-

f-

Twist angle

50°

f-

f-

Color

Pink

f-

f-

GEARING SELECTION The reduction ratio of driven gear to drive gear must be set according to the snow conditions. For many rough surfaces or unfavorable snow conditions, the drive/driven gear ratio should be made larger.lfthere are few rough surfaces orfavorable snow conditions, the ratio should be made smaller.

Gear Ratio Chart The following drive and driven gears and chains are available as options. The figures in the upper lines represent the driven and drive gear ratios, while those in the lower lines represent the number of chain links.

CD Drive gear CV Driven gear CID Reverse gear ÂŽChain

2-41


GEARING SELECTION ,

r~

Gearing Data

2000 ft/600 m (STD)

Item Secondary Drive gear Driven gear Chain

Gear Ratio

19/33 (1.74)

Part No. Teeth

2000 ft - 6000 ft

'fil'

6000 ft/1800 m

19/35 (1.84)

19/38 (2.0)

88T-17682-01

~

~

19T (STD)

~

~

88T-47548-20

Part No.

88T -47548-00

88T-47548-10

Teeth

33T (STD)

35T

38T

Part No.

90880-07076

~

90880-07.078

Links

76T (STD)

~

78T

Chain guide adjustment

1) Align the stationary markCDwith the following chain guide mark A B C. Chain guide mark Drive sprocket teeth

A

B

C

33T

35T

38T

2) Tighten the chain guide bolt. Tightening Torque 20 Nm (2.0 m • kg, 9.4 ft • Ib) 1\ ,

,

\

1\

\\ \\

2-42


~ I_I

HIGH ALTITUDE TUNING 1 HIGH ALTITUDE TUNING

To attain the best performance in high altitude conditions, carefully tune the snowmobile as outlined below.

Confirm STD settings • Carburetor (Page 6-10) • Spark plug (Page 2-3)

+

Adjust main jet size according to the chart (Page 2-34)

Test main jet size (Performance & plug color)

Adjust main jet size

Not OK"

-

I OK

Re-test OK

Not OK

Not OK

OK------------~

Not OK

OK

Not OK

OK-----------r----~

Adjust gearing as required (Page 2-42)

Decide if problem is pilot jet and adjust accordingly NotOK

Not OK

OK

OK ------------'

Check engagement speed and shift performance Not OK

OK---.......~ High altitude tuning OK

Adjust primary clutch as re-

OK

quired (Page 4-3)

Not OK

Not OK

Adjust secondary clutch as required (Page 2-16)

2-43

OK:


SLIDE RAIL SUSPENSION TUNING

Ir8f 1.1

SLIDE RAIL SUSPENSION TUNING Spring Preload Adjustment

NOTE: _________________________ The spring preload is a determining factor in machine stability. Consider the course conditions and the rider's weight when setting the spring preload. The suspension should be set as soft as possible without impairing the stability of the machine. 1. Adjust: • Spring preload.

D

Adjustment steps: • Turn the adjuster Adjuster position [AJ. Adjuster position

ffil· Adjuster position

E

~.

CD in or out. Increase the spring preload. Middle setting position. Decrease the spring preload.

Standard Setting Front [Q] ffil Rear [El: [AJ

AWARNING Always adjust both spring preloads (left and right) to the same setting. Uneven adjustment can cause poor handling and loss of stability .

A'

./

(

2. Adjust: • Stopper band length

''-..

NOTE:------------____________ This adjustment will affect the stability and maneuverability of the machine.

Adjustment steps. • Remove the stopper band and washers.

CD securing bolt CID

• Adjust the length of stopper band. Standard Setting: Front [AJ : No. 1 hole Rear ffil : No. 1 hole

2-44


SLIDE RAIL SUSPENSION TUNING A

IAl :

Front No.5 No.4 No.3 No.2 No.1 (STD)

Hole No.

Maneuverability

No.1

Less (Normal)

1 t

Better

No.5

B

I~ I.1

Straight Starting running acceleration performance performance Less (Normal)

Better (Normal)

t

t

Better

Less

Rear [ffi:

Hole No.

Riding comfort

Stability

No.1

Better (Normal)

Less (Normal)

t

Better

1

No.4

Less

• Tighen the bolt (stopper band).

~

2-45

Nut (stopper band): 4 Nm (0.4 m • kg, 2.9 ft • Ib)

t


_________________ ~H~I~ I CHAPTER 3. CHASSIS STEERING .......................................................... 3-1 REMOVAL .................................................... 3-2 INSPECTION ................................................ 3-4 INSTALLATION ........................................... 3-5 SKI ...................................................................... 3-7 REMOVAL .................................................... 3-8 INSPECTION ................................................ 3-8 INSTALLATION ........................................... 3-9 FRONT SUSPENSION .................................... 3-10 REMOVAL .................................................. 3-11 INSPECTION .............................................. 3-12 INSTALLATION ......................................... 3-13


IS: - .:S~T~E~ER! !I~NIG ICHASIJ I

S:T:E:ER:I:N:-G------icr.iH;:i"A-;;--;;S;S::: CD Handleb"

-

CID

Steering column Bearing ~ Bearing holder ~ Lock washer ® Relay rod (j) Tie-rod

@

®Cap

15 Nm (15 . m·kg , 11ft ·Ib)

27 Nm (27 .

m· kg, 20 ft· Ib)

I A IUSE NEW ONE

I

~~I

r-_--~"rt') •

~

_r"i=-_~-I ... ' u

~~I

ID

~

A~I-;-;u~SE:-:N~E-WO-N-E I

r;1

3-1

-


________________~_E_E_R_IN_G_~H~I~

I

REMOVAL 1. Remove: • Handlebar cover (rear)

CD

2. Disconnect: • Leads CD • Band ®

3. Remove: • Holder (throttle cable) CD 4. Disconnect: • Throttle cable ® (from throttle lever)

5. Remove: • Brake cable Removal steps: • Loosen the locknut CD . • Turn in the adjuster fully ® . • Disconnect the brake cable end brake lever.

3-2

6. Remove: • Handlebar holders (upper)

CD

• Handlebar ® • Handlebar holders (lower)

®

®

from the


________________S_T_EE_R_IN_G_lcHASI...:! 7. Remove: • Main switch holding nut CD • "STARTER" lever holding nut • Center cover ®

I

00

8. Remove • Carburetors (See page 6-4) • Engine assembly (See page 5-1) • Duct (intake silencer) • Intake silencer (See page 6-2)

9. Remove: • • • • • •

Nuts CD Bolts 00 Lock washers Bearing holders ® Bearings@ Steering column CID

NOTE: _ _ _ _ _ _ _ _ _ _ __ When removing the relay rod from the steering column, the relay rod end@needsto be held fixed in order to facilitate the lock nut removal.

10. Remove: • Cotter pins [AJ Left side

rnJ

3-3

Right side

CD


_________________ST_E_E_R_IN_G_lcHASI..=l 11.Remove: • Relay rod CD • Tie rod CV

INSPECTION 1. Inspect: • Handlebar CD • Steering column CV Bending/Cracks/Damage

->

Replace.

AWARNING Do not attempt to straighten a bent column. This may dangerously weaken the column.

2. Inspect: • Bearings (steering column) CD Wear/Damage > Replace. CV (bearing contact • Steering column surfaces) Scratches/Wear/Damage > Replace.

3. Inspect: • Relay rod CD • Tie-rod CV Bending/Cracks/Damage

..

L

Replace .

AWARNING

..........................

.,~

~

~

Do not attempt to straighten a bent rod. This may dangerously weaken the rod.

3-4


________________S_TE_E_R_IN_G_lcHASI..# 4. Check: • Tie-rod end movement Tie-rod end free play exists ---> Replace. Tie-rod end turns roughly ---> Replace.

INSTALLATION Reverse the "REMOVAL" procedure. Note the following points. 1. Install: • Tie-rod CD • Relay rod CID

NOTE: _________________________ • Install the rod end @ with left-hand threads onto the tie-rod on the right side. • The threads on both rod-ends must be the same length.

Si) -t.L. ___ ..

e> _ _ _

Lock Nut (tie-rod end): 25 Nm (2.5 m • kg, 18 ft· Ib) LOCTITE@

~

Nut (suspension bracket-tie-rod): 25 Nm (2.5 kg, 18 ft • Ib) 2. Install: • Cotter pins 3.Apply • Low temperature lithium soap base grease (to bearing inner surface)

4. Install: • Bearings CD • Bearing holders CID • Lock washers @ • Bolts • Nuts [A] Upper [ID Lower

AWARNING Always use a new lock washer and new cotter pin. 3-5


_________________ST_E_E_R_IN_G_lcHASI..# Bolt (bearing holder) 27 Nm (2.7 m • kg, 20 ft· Ib) Nut (steering column relay rod): 27 Nm (2.7 m • kg, 20 ft • Ib)

5. Install: • Intake silencer CD • Duct (intake silencer) (See page 6-2)

CID

6. Install: • Engine assembly • Carburetors • Handlebar

NOTE: _________________________ • The upper handlebar holder should be installed with the punched mark CD forward. • Align the punched marks CID with the handlebar holder gaps respectively. • Tighten the bolts to specification so that the front clearance "a" is smaller than rear clearance "b".

,

-\--~~b

Bolt (handlebar holder): 15 Nm (1.5 m· kg, 11 ft ·Ib)

• Be sure the small gap @ side of the holder faces forward.

3-6


________________~s~~~H~I~1 SKI

CD

Bushing Collar Ski stopper @Ski ÂŽ Ski runner

CV

ÂŽ

Recommended grease: ESSO Beacon 325 grease or Aeroshell grease #7 A

Fit the stopper with its arrow mark positioned in front.

C USE NEW ONE

1 43 Nm (4.3 m - kg, 31 ft - Ib) 1 121 Nm (2.1 m - kg, 1Sft-lb)

4

B Be careful not to reverse the mounting positions of the left and right ski assembly.

3-7


----;;~~~-==----~S~KI ICHASI..# I REMOVAL

1. Elevate the ski by placl·ng a sUlta . b le stand under the chassis. 2. Remove: • Cotter pin CD • Mounting bolt • Nut

CV

3. Remove: • Ski CD • Washers

~.'\:

~'J

• Collar

CV

®

1

®---O

4. Remove:

~/ ',;;C

~~

'iX,'

0

~

• Ski stopper CD • Ski runner nut

-

CV

=-

INSPECTION 1.lnspect: • Ski CD • Ski runner CV Excessive wear/Cracks/Damage (See page 2-23)

2. Inspect:

3-8

• Mounting bolt

CD

• Collar CV Wear/Damage

>

Replace.

>

Replace.


__________________SK_I~H~I~I INSTALLATION Reverse the "REMOVAL" procedure. Note the following points. 1. Install: • Ski runner

CD

Nut (ski runner): 21 Nm (2.1 m· kg, 15 ft ·Ib)

2. Install: • Ski stopper

CD

NOTE: _ _ _ _ _ _ _ _ _ _ __ • Fit the stopper with its arrow mark ® positioned in front. • Be careful not to reverse the mounting positions of the left and right ski assemblies.

3. Lubricate: • Collar CD • Washers CV • Mounting bolt

®--::> •

~

®--o

®

Recommended grease: ESSO Beacon 325 grease or Aeroshell grease #7 A

I--@

4. Install: • Ski 5. Tighten: • Mounting bolt • Nut (ski)

CD

Nut (ski): 43 Nm (4.3 m • kg, 31 ft • Ib) 6. Install: • Cotter pin CV

AWARNING Always use a new cotter pin.

3-9


FRONT SUSPENSION

ICHASI...:!

FRONT SUSPENSION

CD Absorber holder CV Spacer collar @ Flange plate @ Spring seat (upper) @ Bump rubber

® Spring (j)

Spring seat (lower)

® Shock absorber

®

Circlip @Washer

(jJ) Oil seal @ Suspension arm @ Collar @ Bushing @ Bushing @ Front arm (upper) @ Front arm (lower) @ Suspension bracket

Recommended grease: ESSO Beacon 325 grease or Aeroshell grease #7 A

@Setscrew

C USE NEW ONE

I cl USE NEW ONE

43Nm (4.3 m • kg, 31 ft· Ib)

2 Nm (0.2 m· kg, 1.4 ft· Ib) 21 Nm (2.1 m· kg, 15 ft· Ib)

3-10

5Nm (0.5 m • kg, 3.6 ft • Ib)


Thank you very much for your reading. Please Click Here Then Get More Information.

1991 yamaha venture vt480 snowmobile service repair manual  
1991 yamaha venture vt480 snowmobile service repair manual  
Advertisement