Arctic Cat DVX 400 2004 User manual

ATV Service Manual
2004
2004
2004
A A RC C CT TI
®
DVX 400

1
Foreword
This manual contains service, maintenance, and troubleshooting information for the 2004 Arctic Cat DVX 400
ATV model. The manual is designed to aid service personnel in service-oriented applications and may be used as a
textbook for service training.
This manual is divided into sections. Each section covers a specific ATV component or system and, in addition to
the standard service procedures, includes disassembling, inspecting, and assembling instructions. When using this
manual as a guide, the technician should use discretion as to how much disassembly is needed to correct any given
condition. A troubleshooting section is also included in this manual.
The service technician should become familiar with the operation and construction of each component or system
by carefully studying this manual. This manual will assist the service technician in becoming more aware of and
efficient with servicing procedures. Such efficiency not only helps build consumer confidence but also saves time
and labor.
All Arctic Cat ATV publications and decals display the words Warning, Caution, Note, and At This Point to
emphasize important information. The symbol ! WARNING identifies personal safety-related information.
Be sure to follow the directive because it deals with the possibility of severe personal injury or even death. The
symbol !CAUTIONidentifies unsafe practices which may result in ATV-related damage. Follow the direc-
tive because it deals with the possibility of damaging part or parts of the ATV. The symbol NOTE: identifies
supplementary information worthy of particular attention. The symbol AT THIS POINT directs the tech-
nician to certain and specific procedures to promote efficiency and to improve clarity.
At the time of publication, all information, photographs, and illustrations were technically correct. Some photo-
graphs used in this manual are used for clarity purposes only and are not designed to depict actual conditions.
Because Arctic Cat Inc. constantly refines and improves its products, no retroactive obligation is incurred.
All materials and specifications are subject to change without notice.
Keep this manual accessible in the shop area for reference.
Product Service and
Warranty Department
Arctic Cat Inc.
© 2004 Arctic Cat Inc. January 2004
®™ Trademarks of Arctic Cat Inc., Thief River Falls, MN 56701

3
TABLE OF CONTENTS
Section
1. General Information
2. Periodic Maintenance/Tune-Up
3. Engine/Transmission
4. Fuel/Lubrication/Cooling
5. Electrical System
6. Drive System
7. Suspension
8. Steering/Frame
9. Controls/Indicators
10. Aids for Maintenance
11. Troubleshooting
1
2
3
4
5
6
7
8
9
10
11

1
SECTION 1 - GENERAL INFORMATION
TABLE OF
CONTENTS
General Specifications ............................................1-2
Break-In Procedure.................................................1-3
Gasoline - Oil - Lubricant ........................................1-3
Genuine Parts .........................................................1-4
Preparation For Storage..........................................1-5
Preparation After Storage........................................1-5

2
General Specifications*
* Specifications subject to change without notice.
Break-In Procedure
A new ATV and an overhauled ATV engine require a
“break-in” period. The first 10 hours (or 200 miles) are
most critical to the life of this ATV. Proper operation
during this break-in period will help assure maximum life
and performance from the ATV.
During the first 10 hours (or 200 miles) of operation,
always use less than 1/2 throttle. Varying the engine
RPM during the break-in period allows the components
to “load” (aiding the mating process) and then “unload”
(allowing components to cool). Although it is essential to
place some stress on the engine components during
break-in, care should be taken not to overload the engine
too often. Do not pull a trailer or carry heavy loads
during the 10-hour break-in period.
When the engine starts, allow it to warm up properly. Idle
the engine several minutes until the engine has reached
normal operating temperature. Do not idle the engine for
excessively long periods of time.
During the break-in period, a maximum of 1/2 throttle is
recommended; however, brief full-throttle accelerations
and variations in driving speeds contribute to good
engine break-in.
During the break-in period (or whenever the brake pads
are replaced), the hydraulic brake pads must be bur-
nished. Slow disc-speed hydraulic brakes must be prop-
erly burnished in order to achieve maximum stopping
power.
NOTE: Do not be reluctant to heat up the brake
pads during the burnishing procedure.
CARBURETOR
Type Mikuni BSR36
Main Jet 130
Pilot Jet 27.5
Low Speed Fuel Screw Setting (turns) 2 1/4
Jet Needle SE26-1
Needle Jet P-OM
Idle RPM 1250-1350
Float Arm Height 12-14 mm (0.47-0.55 in.)
Throttle Cable Free-Play (at lever) 3-6 mm (1/8-1/4 in.)
ELECTRICAL
Spark Plug Type NGK CR7E
Spark Plug Gap 0.7-0.8 mm (0.028-0.032 in.)
Ignition Coil Resistance (primary)
(secondary)
0.1-1.0 ohm
(terminal to ground)
13,000-20,000 ohms
(high tension - plug cap
removed - to terminal)
Ignition Coil Peak (primary/CDI)
Voltage More than 130 volts (terminal to ground)
Magneto Coil Resistance (trigger)
(charging)
350-670 ohms (black/yellow to
green/white)
0.1-1.5 ohms (yellow to yellow)
Magneto Coil Peak Voltage (trigger)
(charging)
More than 2.0 volts (green to
blue)
More than 65.0 volts AC at
alternator lead coupler
Magneto Output (approx) 150W @ 5000 RPM
CHASSIS
Dry Weight (approx) 169 kg (373 lb)
Length (overall) 183 cm (72 in.)
Height (overall) 116 cm (45.7 in.)
Width (overall) 116.5 cm (45.8 in.)
Suspension Travel Front - 21.5 cm (8.4 in.)
Rear - 22.5 cm (8.6 in.)
Ground Clearance 20.3 cm (8.0 in.)
Brake Type Hydraulic Disc and Mechani-
cal Parking Brake
Wheelbase 124.5 cm (49 in.)
Tire Size Front - AT22 x 7R10
Rear - AT20 x 10R9
Tire Inflation Pressure Front - 0.30 kg/cm² (4.3 psi)
Rear - 0.27 kg/cm² (3.9 psi)
Turning Radius 3.1 m (10.2 ft)
MISCELLANY
Gas Tank Capacity (rated) 10.0 L (2.6 U.S. gal.)
Reserve Capacity 0.7 L (0.18 U.S. gal.)
Engine Oil Capacity 2.1 L (2.2 U.S. qt)
Gasoline (recommended) 87 Octane Regular Unleaded
Engine Oil (recommended) SAE 10W-40
Cooling System Capacity 1.2 L (1.3 U.S. qt)
Brake Fluid DOT 4
Taillight/Brakelight 12V/5W/21W
Headlight 12V/27W (2)/12V/50W (1)
Starting System Electric
! CAUTION
BRAKE PADS MUST BE BURNISHED TO ACHIEVE
FULL BRAKING EFFECTIVENESS. Braking
distance will be extended until brake pads are
properly burnished.
TO PROPERLY BURNISH THE BRAKES, USE
FOLLOWING PROCEDURE:
Choose an area sufficiently large to safely
accelerate ATV to 30 mph and to brake to a stop.
Accelerate to 30 mph; then apply front and rear
brakes to decelerate to 0-5 mph.
Repeat procedure five times until brakes are
burnished.
This procedure burnishes the brake pads,
stabilizes the pad material, and extends the life of
the brake pads.
! WARNING
Do not attempt sudden stops or put the ATV into a
situation where a sudden stop will be required
until the brake pads are properly burnished.

3
After the completion of the break-in period, the engine
oil and oil filter should be changed. Other maintenance
after break-in should include checking of all prescribed
adjustments and tightening of all fasteners.
Gasoline - Oil - Lubricant
RECOMMENDED GASOLINE
The recommended gasoline to use is 87 minimum octane
regular unleaded. In many areas, oxygenates (either etha-
nol or MTBE) are added to the gasoline. Oxygenated
gasolines containing up to 10% ethanol, 5% methane, or
5% MTBE are acceptable gasolines.
When using ethanol blended gasoline, it is not necessary
to add a gasoline antifreeze since ethanol will prevent the
accumulation of moisture in the fuel system.
RECOMMENDED ENGINE/
TRANSMISSION OIL
The recommended oil to use is Arctic Cat 4-Cycle
Engine Oil (p/n 0436-005) or an equivalent oil which
is rated SE, SF, or SG under API service classification.
These oils meet all of the lubrication requirements of
the Arctic Cat ATV engine. The recommended engine
oil viscosity is SAE 10W-40. Ambient temperature
should determine the correct weight of oil. See the
following viscosity chart for details.
OILCHARTA
FILLING GAS TANK
ATV0049B
Since gasoline expands as its temperature rises, the gas
tank must be filled to its rated capacity only. Expansion
room must be maintained in the tank particularly if the
tank is filled with cold gasoline and then moved to a
warm area.
Tighten the gas tank cap securely after filling the tank.
Genuine Parts
When replacement of parts is necessary, use only genuine
Arctic Cat ATV parts. They are precision-made to ensure
high quality and correct fit. Refer to the appropriate Illus-
trated Parts Manual for the correct part number, quantity,
and description.
Preparation For Storage
Arctic Cat recommends the following procedure to pre-
pare the ATV for storage.
1. Clean the seat cushion (cover and base) with a damp
cloth and allow it to dry.
! CAUTION
Do not use white gas. Only Arctic Cat approved
gasoline additives should be used.
! CAUTION
Any oil used in place of the recommended oil
could cause serious engine damage. Do not use
oils which contain graphite or molybdenum
additives. These oils can adversely affect clutch
operation. Also, not recommended are racing,
vegetable, non-detergent, and castor-based oils.
! WARNING
Always fill the gas tank in a well-ventilated area.
Never add fuel to the ATV gas tank near any open
flames or with the engine running. DO NOT
SMOKE while filling the gas tank.
! WARNING
Do not overflow gasoline when filling the gas tank.
A fire hazard could materialize. Always allow the
engine to cool before filling the gas tank.
! WARNING
Do not over-fill the gas tank.
! CAUTION
Prior to storing the ATV, it must be properly
serviced to prevent rusting and component
deterioration.

4
2. Clean the ATV thoroughly by washing dirt, oil,
grass, and other foreign matter from the entire ATV.
Allow the ATV to dry thoroughly. DO NOT get
water into any part of the engine or air intake.
3. Either drain the gas tank or add Fuel Stabilizer (p/n
0638-165) to the gas in the gas tank. Remove the air
filter housing cover and air filter. Start the engine and
allow it to idle; then using Arctic Cat Engine Storage
Preserver (p/n 0636-177), rapidly inject the preserver
into the air filter opening for a period of 10 to 20 sec-
onds; then stop the engine. Install the air filter and
housing cover.
4. Drain the carburetor float chamber.
5. Plug the exhaust hole in the exhaust system with a
clean cloth.
6. Apply light oil to the upper steering post bushing,
plungers of the shock absorbers, and drive chain.
7. Tighten all nuts, bolts, cap screws, and screws. Make
sure rivets holding components together are tight.
Replace all loose rivets. Care must be taken that all
calibrated nuts, cap screws, and bolts are tightened to
specifications.
8. Fill the cooling system to the upper level line on the
overflow tank with properly mixed coolant.
9. Disconnect the battery cables; then remove the bat-
tery, clean the battery posts and cables, and store in a
clean, dry area.
10. Store the ATV indoors in a level position.
Preparation After
Storage
Taking the ATV out of storage and correctly preparing it
will assure many miles and hours of trouble-free riding.
Arctic Cat recommends the following procedure to pre-
pare the ATV.
1. Clean the ATV thoroughly.
2. Clean the engine. Remove the cloth from the exhaust
system.
3. Check all control wires and cables for signs of wear
or fraying. Replace if necessary.
4. Change the engine/transmission oil and filter.
5. Check the coolant level and add properly mixed
coolant as necessary.
6. Charge the battery; then install. Connect the battery
cables.
7. Check the entire brake systems (fluid level, pads,
etc.), all controls, headlights, taillight, brakelight,
and headlight aim; adjust or replace as necessary.
8. Tighten all nuts, bolts, cap screws, and screws mak-
ing sure all calibrated nuts, cap screws, and bolts are
tightened to specifications.
9. Check tire pressure. Inflate to recommended pressure
as necessary.
10. Make sure the steering moves freely and does not
bind.
11. Check the spark plug. Clean or replace as necessary.
12. Follow the recommendations found in the pre-start
inspection.
13. Inspect the drive chain and sprockets. Adjust or
replace as necessary.
! CAUTION
If the interior of the air filter housing is dirty, clean
the area before starting the engine.
! CAUTION
Avoid storing outside in direct sunlight and avoid
using a plastic cover as moisture will collect on
the ATV causing rusting.

1
SECTION 2 -
PERIODIC MAINTENANCE/TUNE-UP
Table of Contents
Periodic Maintenance Chart.................................... 2-2
Lubrication Points.................................................... 2-3
Battery..................................................................... 2-3
Fuses ...................................................................... 2-4
Air Cleaner.............................................................. 2-4
Valve/Tappet Clearance ......................................... 2-6
Tappet Shim Selection Table (Exhaust) ................. 2-9
Tappet Shim Selection Table (Intake).................... 2-10
Testing Engine Compression ................................ 2-11
Spark Plug ............................................................ 2-11
Muffler/Spark Arrester........................................... 2-12
Gas/Vent Hoses.................................................... 2-12
Adjusting Throttle Cable........................................ 2-12
Adjusting Engine RPM (Idle).................................2-13
Engine/Transmission Oil - Filter.............................2-13
Adjusting Clutch Lever Cable................................2-14
Tires ......................................................................2-15
Steering Components ...........................................2-15
Suspension/Shock Absorbers/Bushings ...............2-15
Nuts/Bolts/Cap Screws..........................................2-15
Headlight/Taillight-Brakelight.................................2-15
Switches................................................................2-17
Indicator Lights......................................................2-17
Frame/Welds .........................................................2-17
Electrical Connections...........................................2-17
Hydraulic/Parking Brake Systems.........................2-17
Burnishing Brake Pads..........................................2-22
Coolant..................................................................2-22
Drive Chain............................................................2-22

2
Periodic Maintenance
Chart
* Service/Inspect more frequently when operating in adverse
conditions.
Item Initial Service After Break-In
(First Mo) Every
Day Every Month Every 3 Months Every 6 Months Every Year As Needed
Battery Charge C
Fuse IR
Air Filter/Drain Tube IIC* R
Valve/Tappet Clearance IIA
Engine Compression I
Spark Plug I I R (18 Mo)
Muffler/Spark Arrester CR
Gas/Vent Hoses II R(2Yrs)
Gas Tank Valve IC
Throttle Cable II C-L A-R
Carb Float Chamber D*
Engine RPM (Idle) IIA
Engine-Transmission Oil Level I A
Engine-Transmission Oil/Filter RR*R
Oil Strainer IIC
Drive Chain IIA R
Clutch IlA
Tires/Air Pressure II R
Steering Components II R
Coolant Hoses IlR(4yrs)
Suspension (Ball joint and tie rod boots,
tie rods, and shock mounts) Il*R
Nuts/Cap Screws/Screws II A
Oil Lines II
Headlight/Taillight- Brakelight II R
Switches II R
Reverse Selector Cable IIA-L
Choke Cable IIC-LR
Handlebar Grips I R
Handlebars II R
Indicator Lights II R
Frame/Welds II l
Electrical Connections lC
Complete Brake Systems (Hydraulic &
Parking) II C L-R
Brake Pads II*R
Brake Fluid IIR(2Yrs)
Brake Hoses IIR(4Yrs)
Brake Cable (Parking) I-A
Coolant/Cooling System II R(2Yrs)
A = Adjust I = Inspect
C = Clean L = Lubricate
D = Drain R = Replace

3
Lubrication Points
It is advisable to lubricate certain components periodi-
cally to ensure free movement. Apply light oil to the
components using the following list as reference.
A.Throttle Lever Pivot/Cable Ends
B. Brake Lever Pivot
C. Parking Brake Cable Ends
D.Choke Cable Upper End
E. Reverse Selector Cable End
F. Idle RPM Screw (Carburetor)
G. Rear Brake Pedal Pivot
Battery
The battery is located under the seat.
The battery in this ATV is a “sealed” type and does not
require any maintenance unless discharged. Distilled
water and/or electrolyte cannot be added to the battery.
SP034
This maintenance-free battery requires periodic charging
to prevent sulfiding. If the ATV will be idle for extended
periods of time, either run the engine or trickle charge
from time to time. If the battery completely discharges,
permanent damage will occur requiring replacement.
If the battery is discharged, remove the battery from the
ATV and charge the battery at the standard charging rate
of 0.9 amps for 5-10 hours.
To remove and charge the battery, use the following pro-
cedure.
1. Remove the seat; then remove the battery hold-down
bracket.
2. Remove the negative battery cable; then remove the
positive cable and the battery vent tube. Remove the
battery from the ATV. Care should be taken not to
damage the vent tube.
3. Trickle charge the battery at 0.9 amps for 5-10 hours.
4. Place the battery into position in the ATV and secure
with the hold-down bracket.
5. Connect cables to the proper terminals: positive
cable to the positive terminal (+) and negative cable
to the negative terminal (-). Connect the negative
cable last.
SP034
6. Install the seat making sure it locks securely.
Fuses
There is one 20 amp fuse and one spare 20 amp fuse
located adjacent to the battery on the starter relay.
! WARNING
Anytime service is performed on a battery, the fol-
lowing must be observed: Keep sparks, open flame,
cigarettes, or any other flame away. Always wear
safety glasses. Protect skin and clothing when han-
dling batteries. When servicing battery in enclosed
space, keep the area well-ventilated.
! WARNING
Avoid spillage and contact with skin, eyes, and cloth-
ing.
! CAUTION
Do not charge the battery while it is in the ATV
with the battery terminals connected.
! CAUTION
Never exceed the standard charging rate.
! CAUTION
Before installing the battery, make sure the
ignition switch is in the OFF position.
! CAUTION
Connecting cables in reverse (positive to negative
and negative to positive) can cause serious
damage to the electrical system.

4
If there is any type of electrical system failure, always
check the fuse first.
SP032A
Air Cleaner
The air filter inside the air cleaner must be kept clean
to provide good engine power and gas mileage. If the
ATV is used under normal conditions, service the filter
at the intervals specified. If operated in dusty, wet, or
muddy conditions, inspect and service the filter more
frequently.
CLEANING AND INSPECTING FILTER
1. Remove the seat.
2. Unseat the two retaining clips securing the air
cleaner housing cover; then remove the cover.
SP014A
3. Remove the screw securing the air filter stopper and
set aside; then remove the filter assembly.
SP012
4. Remove the foam wrap from the filter frame.
SP013
5. Fill a wash pan larger than the filter with a non-flam-
mable cleaning solvent; then dip the filter in the sol-
vent and wash it.
NOTE: Foam Filter Cleaner (p/n 0436-194) and
Foam Filter Oil (p/n 0436-195) are available from
Arctic Cat.
6. Dry the filter.
7. Put the filter in a plastic bag; then pour in air filter oil
and work the filter.
8. Clean any dirt or debris from inside the air cleaner.
Be sure no dirt enters the carburetor.
9. Place the filter in the air filter housing making sure it
is properly in position and properly seated and secure
with the stopper and screw.
10. Install the air filter housing cover and secure with the
retaining clips; then install the seat making sure the
seat is properly secured.
! CAUTION
Always replace a blown fuse with a fuse of the
same type and rating.
! CAUTION
Failure to inspect the air filter frequently if the ATV
is used in dusty, wet, or muddy conditions can
damage the ATV engine.
! CAUTION
A torn air filter can cause damage to the ATV
engine. Dirt and dust may get inside the engine if
the element is torn. Carefully examine the element
for tears before and after cleaning it. Replace the
element with a new one if it is torn.

5
CHECKING/DRAINING DRAIN TUBE
1. Periodically check the drain tube for gasoline or oil
accumulation. If noticed, remove the drain tube cap
from beneath the front housing, drain the gasoline or
oil into a suitable container, and install and secure
the tube cap.
2. Inspect one-way drain tube beneath the main housing
for debris and for proper sealing.
SP119
REMOVING
1. Remove the seat.
2. Unseat the two retaining clips securing the air
cleaner housing; then remove the cover.
SP014A
3. Remove the screw securing the air filter stopper and
set aside; then remove the air filter.
SP012
4. Loosen the clamp securing the air cleaner to the inlet
duct; then loosen the clamp securing the air cleaner
to the outlet tube.
5. Remove the cap screws securing the air cleaner to
the frame.
6. Remove the air cleaner from the frame.
INSTALLING
0739-212
1. Place the air cleaner into the frame.
2. Install the cap screws securing the air cleaner to the
frame.
3. Install the outlet tube onto the air cleaner; then
tighten the clamp securely.
4. Install the inlet duct onto the air cleaner; then tighten
the clamp securely.
5. Install the filter with foam wrap into the air cleaner;
then tighten the filter stopper screw securely.
SP012
6. Place the air cleaner cover into position and secure
with the retaining clips.
KEY
1. Air Cleaner Assy
2. Filter
3. Holder
4. Stopper
5. Screw
6. Outlet Tube
7. Elbow Fitting
8. Breather Plug
9. Clip
10. Clamp
11. Clamp
12. Flame Trap
13. Cover
14. Gasket
15. Inlet Joint
16. Inlet Duct
17. Clamp

6
SP014A
7. Install the seat making sure the seat is properly
secured.
Valve/Tappet Clearance
CHECKING
To check and adjust valve/tappet clearance, use the fol-
lowing procedure.
1. Remove the seat, gas tank cover, and body.
2. Turn the fuel valve to the “ON” position; then
remove the gas tank.
3. Disconnect the engine oil hose (3) and the engine oil
breather hose (4); then remove the spark plug.
SP120
4. Remove the three large Allen-head cap screws secur-
ing the valve cover; then remove the valve cover
accounting for the two camshaft end plugs and the
valve cover gasket.
SP121
NOTE: The valve/tappet clearance specification
is different for intake and exhaust valves. The
clearance should only be checked when the
engine is cold (room temperature).
NOTE: Valve/tappet clearance adjustment must
be checked and adjusted in accordance with the
periodic maintenance chart or anytime valve
mechanism components are removed and rein-
stalled.
5. Remove the valve timing inspection plug (1) and the
generator cover cap (2); then rotate the crankshaft
with a socket wrench to top-dead-center (TDC) on
the compression stroke. The “T” line on the alterna-
tor rotor is aligned with the triangle mark on the
alternator cover.
SP122
SP123

7
NOTE: The camshaft lobes must be in position
(A) in order to check valve/tappet clearance.
SP124
6. Insert a feeler gauge between the tappet and the cam-
shaft. The clearance must be within specifications.
SP125
If the clearance is out of specifications, adjust the clear-
ance using the following procedure.
ADJUSTING
The clearance is adjusted by replacing the existing tappet
shim with a thicker or thinner shim.
1. Remove the camshaft corresponding to the out-of-
tolerance tappet. See Section 3.
2. Using a magnet, remove the tappet and shim; then
check the numbers printed on the tappet shim.
ATV2151
NOTE: These numbers indicate the thickness of
the tappet shim as illustrated.
3. Select a replacement tappet shim that will provide
the proper clearance.
NOTE: Tappet shims are available in 25 sizes
from 2.30-3.50 mm (0.09-0.14 in.) in 0.05 mm (0.002
in.) increments.
4. Install the selected shim at the valve stem with the
numbers facing the tappet. Be sure to measure the
shim with a micrometer to ensure it is the proper
size. Refer to the tappet shim selection table for
details.
NOTE: Apply molybdenum oil solution to the top
and bottom of the tappet shim. Make sure that the
numbered side is directed toward the tappet.
5. Install the camshaft (see Section 3).
6. Rotate the crankshaft through two full revolutions to
ensure that all excess oil is squeezed from the valve/
tappet clearance to make sure it is within specifica-
tions.
7. Apply Three Bond Sealant (p/n 0636-070) to the
camshaft end caps of the valve cover gasket; then
install the valve cover.
8. Tighten the valve cover cap screws to specifications.
9. Install the spark plug and tighten to specifications;
then install the timing inspection plug.

8
ATV2152

9
ATV2153

10
Testing Engine
Compression
To test engine compression, use the following procedure.
1. Remove the high tension lead from the spark plug.
2. Using compressed air, blow any debris from around
the spark plug.
3. Remove the spark plug; then attach the high tension
lead to the plug and ground the plug on the cylinder
head well away from the spark plug hole.
4. Attach the Compression Gauge (p/n 0444-096).
NOTE: The engine must be warm and the battery
must be fully charged for this test.
5. While holding the throttle lever in the full-open posi-
tion, crank the engine over with the electric starter
until the gauge shows a peak reading (five to 10
compression strokes). The compression should be
10.0 kg/cm2(142 psi).
6. If compression is abnormally low, inspect the
following items.
A. Verify starter cranks engine over at normal
cranking speed.
B. Gauge is functioning properly.
C. Throttle lever in the full-open position.
D. Valve/tappet clearance correct.
E. Valve bent or burned.
F. Valve seat burned.
NOTE: To service valves, see Section 3.
7. Pour 29.5 ml (1 fl oz) of oil into the spark plug hole,
reattach the gauge, and retest compression.
8. If compression is now evident, service the piston
rings (see Section 3).
Spark Plug
A light brown insulator indicates that the plug is correct.
A white or dark insulator indicates that the engine may
need to be serviced or the carburetor may need to be
adjusted. To maintain a hot, strong spark, keep the plug
free of carbon.
ATV-0051
Adjust the gap to 0.7 - 0.8 mm (0.028 - 0.032 in.). Use a
feeler gauge to check the gap.
ATV0052B
When installing the spark plug, tighten to specifications.
Muffler/Spark Arrester
The muffler has a spark arrester which must be periodi-
cally cleaned. At the intervals shown in the Periodic
Maintenance Chart, clean the spark arrester using the fol-
lowing procedure.
1. Remove the three Allen-head cap screws securing
the spark arrester to the muffler; then remove the
spark arrester.
! WARNING
Always wear safety glasses when using compressed
air. ! CAUTION
Before removing the spark plug, be sure to clean
the area around the spark plug. Dirt could enter
engine when removing or installing the spark
plug.
! WARNING
Wait until the muffler cools to avoid burns.

11
SP001
2. Use a wire brush to remove carbon deposits from the
arrester taking care not to damage the screen.
SP041
3. Check the arrester screen for holes or tears and
replace components as necessary.
4. Install the spark arrester and three cap screws and
tighten securely.
Gas/Vent Hoses
Replace the gas hose every two years. Damage from
aging may not always be visible. Do not bend or obstruct
the routing of the carburetor vent hose. Make certain that
the vent hose is securely connected to the carburetor and
the opposite end is always open.
Adjusting Throttle Cable
To adjust the throttle cable free-play, follow this proce-
dure.
1. Slide the rubber boot away; then loosen the jam nut
from the throttle cable adjuster.
AL611D
2. Slide the rubber boot away and turn the adjuster until
the throttle cable has proper free-play of 3-6 mm (1/8
- 1/4 in.) at the lever.
ATV-0047
3. Tighten the jam nut against the throttle cable adjuster
securely; then slide the rubber boot over the adjuster.
Adjusting Engine RPM
(Idle)
To properly adjust the idle RPM, a tachometer is neces-
sary. To adjust idle RPM, use the following procedure.
1. With the transmission in neutral, start the engine and
warm it up to normal operating temperature.
2. Turn the idle adjustment screw (on the left side of the
carburetor) clockwise one turn past the recom-
mended RPM setting; then turn it counterclockwise
to 1250-1350 RPM.

12
SP008A
Engine/Transmission
Oil - Filter
OIL - FILTER
Change the engine oil and oil filter at the scheduled inter-
vals. The engine should always be warm when the oil is
changed so the oil will drain easily and completely.
1. Park the ATV on level ground.
2. Loosen the oil level stick enough to allow air to vent
the tank.
SP016A
3. Place drain pans under the oil tank drain plug (1) and
the crankcase drain plug (2); then remove the plugs
and drain the oil.
ATV2027
ATV2028
4. Remove the cap screws securing the filter cover.
5. Remove the filter cover (3); then pull out the oil filter
element (4) and properly discard. Remove and prop-
erly discard the O-ring from the filter cover.
ATV2029
NOTE: Clean up any excess oil after removing
the filter.
! WARNING
Adjust the idle to the correct RPM. Make sure the
engine is at normal operating temperature before
adjusting the idle RPM.

13
ATV2030
6. Apply oil to a new cover O-ring and check to make
sure it is positioned correctly in the cover. With the
open end of the filter element directed toward the
center of the engine, slide the element into position.
0739-215
7. Place the filter cover in position with the triangle
mark up and secure with the cap screws. Tighten
securely.
8. Install the crankcase drain plug and tighten to speci-
fications; then install the oil tank drain plug and
tighten to specifications.
9. Pour the recommended type and quantity of oil into
the oil level stick hole; then start the engine (while
the ATV is outside on level ground) and allow it to
idle for a few minutes.
10. Turn the engine off and wait approximately one minute.
Recheck the oil level with the oil level stick. The oil
level should be between the upper and lower crosshatch
marks on the level stick. Adjust oil level as necessary.
ATV2020A
11. Inspect the area around the drain plugs and oil filter
for leaks.
Adjusting Clutch Lever
Cable
To adjust the cable, use the following procedure.
1. Pull rubber protective boot away from the cable
adjusters.
2. Loosen the lock nut; then turn the adjuster to obtain 10-
15 mm (0.4-0.6 in.) free-play measured at point (A).
SP126
Tires
TIRE SIZES
The ATV is equipped with low-pressure tubeless tires of
the size and type listed. Do not under any circumstances
substitute tires of a different type or size.
! CAUTION
If the oil filter element is inserted backwards,
engine damage will occur due to lack of oil flow.
! CAUTION
Any oil used in place of the recommended oil
could cause serious engine damage. Do not use
oils which contain graphite or molybdenum
additives. These oils can adversely affect clutch
operation. Also, not recommended are racing,
vegetable, non-detergent, and castor-based oils.
KEY
1. Oil Pump Assy
2. Driven Gear
3. Pin
4. Washer
5. Circlip
6. Cap Screw
7. Rotor Set
8. Strainer
9. Cap Screw
10. Oil Filter
11. O-Ring
12. Oil Filter Cover
13. O-Ring
14. Spring
15. Cap Screw
16. Spring
17. Ball
18. Oil Check-Valve Seat
19. Gear
20. Shaft
21. Circlip
! WARNING
Always use the size and type of tires specified.
Always maintain proper tire inflation pressure.