Snowmobile Polaris ProStar S4, Indy XC 129 / 137, Indy Adventure 137, Voyageur 146, Nordic Pro 146. Owner’s Manual (2024)

TRACK WARM-UP

WARNING

A loose track or flying debris could cause serious injury or death. Stand clear of

the front of the snowmobile and the moving track. Never hold the snowmobile

up or stand behind it while warming up the track. Do not use excessive throttle

during warm-up or when the track is free-hanging. Use a stable rear support.

WARNING

Use of traction products such as studs, ice growsers, etc. will increase the
possibility of track damage and/or failure. This could cause loss of control,

resulting in serious injury or death. Always inspect for track damage before

operating the snowmobile.

Follow these steps to ensure proper warm-up of the engine, drive train and
track.

1. Use an appropriate stand to securely support the rear of the snowmobile at

the rear bumper. The track should be about 4 inches (10 cm) off the ground.

2. Start the engine and allow it to warm up two to three minutes.

3. Depress the throttle abruptly and allow the track to rotate several revolutions.

TIP

It will take longer to warm up the track sufficiently during colder outdoor

temperatures.

4. Release the throttle, apply the brakes, shut off the engine and lower the

snowmobile to the ground.

5. Grasp the skis by their front loops and move them from side to side to loosen

snow and ice.

SLIDE RAIL AND TRACK COOLING

NOTICE

Inadequate cooling and lubrication will lead to overheating of the slide rail and

track, resulting in premature wear and failure. Reduce speeds and frequently

drive into fresh snow to allow adequate cooling and polishing of the slide rail

and track surfaces. Avoid operating on ice, hard-packed surfaces or roads.

135

OPERATION

FUEL RECOMMENDATION

WARNING

Gasoline is highly flammable and explosive under certain conditions.

• Always exercise extreme caution whenever handling gasoline.
• Always refuel outdoors or in a well-ventilated area.
• Always turn off the engine before refueling.
• Do not overfill the tank. Do not fill the tank neck.
• Do not smoke or allow open flames or sparks in or near the area where

refueling is performed or where gasoline is stored.

• If gasoline spills on your skin or clothing, immediately wash it off with soap

and water and change clothing.

• Never start the engine or let it run in an enclosed area. Engine exhaust

fumes are poisonous and can cause loss of consciousness or death in a
short time.

WARNING

The engine exhaust from this product contains chemicals known to cause
cancer, birth defects or other reproductive harm. Operate this vehicle only

outdoors or in well-ventilated areas.

NORTH AMERICAN FUEL

For peak performance, POLARIS recommends the use of 87 octane fuel or
higher, with no more than 10% ethanol. Do not use lower than 87 octane fuel.
Operating with obstructed fuel systems will result in serious engine damage.
Perform maintenance as recommended. Prolonged exposure to petroleum
based products may damage paint. Always protect painted surfaces when
handling fuel.

The tables below indicate the recommended fuel for your ProStar engine.

IMPORTANT

Do not use fuel containing more than 10% ethanol. Never use E85 or 88 E15

fuel in your snowmobile.

136

OPERATION

PROSTAR S4 MODELS

ETHANOL CONTENT

87 (R+M)/2

91 (R+M)/2

Non-Ethanol Fuel

STANDARD

Up to 10% Ethanol

OPTIMUM

STANDARD

Shaded cells indicate the optimum fuel recommendation for this engine.

INTERNATIONAL FUEL

For peak performance, POLARIS recommends the use of 95 octane E10
gasoline or higher octane. If lower octane is used, some engine performance will
be lost and fuel economy will decrease. Do not use gasoline with higher ethanol
rating than E10.

The tables below indicate the recommended fuel for your ProStar engine.

PROSTAR S4 MODELS

ETHANOL CONTENT

95 RON

98 RON

Non-Ethanol

STANDARD

1-10% Ethanol or
MTBE

OPTIMUM

STANDARD

Shaded cells indicate the optimum fuel recommendation for this engine.

FUEL SYSTEM DEICERS

If you use non-ethanol fuel (sometimes labeled “non-oxygenated”), POLARIS
recommends the regular use of isopropyl-based fuel system deicer. Add 1-2
ounces per gallon (8-16 ml per liter) of gasoline to prevent damage resulting
from fuel system icing. Never use deicers or additives containing methanol.
POLARIS recommends the use of Carbon Clean.

IMPORTANT

If you use fuel with up to 10% ethanol (sometimes labeled “oxygenated”) do

not add deicers or additives that contain any form of alcohol. Adding deicer to

oxygenated fuels could result in severe engine damage.

137

OPERATION

OIL RECOMMENDATION

Polaris Recommended Engine Oil

PS-4 Extreme 0W-50 Full Synthetic Engine Oil

NOTICE

NEVER mix oil brands or use non-recommended oil. Engine damage caused

by mixing oil or using non-recommended oil may not be covered by the Polaris

limited warranty.

THROTTLE LEVER

WARNING

An improperly functioning throttle lever may cause erratic snowmobile behavior

and loss of control, which could result in serious injury or death. If the throttle

lever does not work properly, DO NOT start the engine.

If the engine stops abruptly when the throttle lever is released, do the following:

1. Turn the ignition switch to OFF.

2. Test the throttle lever by compressing and releasing it several times. The

lever must return to the idle position quickly and completely.

3. If the throttle lever operates properly, turn the ignition switch on and go

through normal starting procedures.

4. If the engine doesn't start, see your authorized POLARIS dealer or other

qualified technician for service.

ENGINE STOP SWITCH

Push down on the engine stop
switch

to ground out the

ignition and stop the engine
quickly. Pull the switch up to the
ON position to allow restarting.

138

OPERATION

EMERGENCY STOPPING

The following chart lists methods for stopping the snowmobile in the event of an
emergency.

SYSTEM

WHAT IT DOES

Ignition Switch

Interrupts ignition circuit

Brake

Slows jackshaft

Engine Stop Switch

Interrupts ignition circuit

Tether Switch

Interrupts ignition circuit

VEHICLE TIPOVER

In the event of a tipover, or if the snowmobile is tipped on its side at an angle of
65 degrees or greater, the engine will automatically shut off after one second.

To restart the engine, turn the snowmobile over so the skis and track are flat on
the ground. Then follow the normal restarting procedure on page 133.

DAILY STORAGE

At the end of each ride, park the snowmobile on a level surface and support it at
the rear with an appropriate track stand. The track should be suspended
approximately 4 inches (10 cm) off the ground.

Remove the key and cover the snowmobile.

TOWING

For your safety, do not attempt to use a tow hitch until you've read the following
warnings and understand the proper hitch functions.

WARNING

Objects towed with a rope have no braking power and can easily collide with

the rear of the snowmobile or other objects, resulting in serious injury or death.

DO NOT tow toboggans, sleds, saucers, or any type of vehicle with a rope.

Only a stiff metal pole connecting the towed object and the tow hitch on the

snowmobile should be used. If passengers are to be towed on a toboggan or

sled, make sure the pole is at least four feet (1.2 meters) long to prevent any

possibility of contact between the snowmobile's track and a person riding in the

towed object.

139

OPERATION

WARNING

Braking distances increase when towing loads. Slow down to maintain control

of the snowmobile.

If the snowmobile becomes inoperable and must be towed, and if it isn't possible
to use a rigid tow bar, attach the tow rope to the ski spindles (not to the ski loops)
to prevent damage to the steering components. Remove the drive belt before
towing, and have someone ride on the towed snowmobile to operate the brake
and steering when necessary.

NOTICE

Towing a disabled snowmobile with the drive belt in place can result in serious

damage to the engine and drive system. Always remove the drive belt from a

disabled snowmobile before towing.

140

OPERATION

SNOWMOBILE BREAK-IN

ENGINE BREAK-IN

IMPORTANT

Engines equipped with an electronic oil pump do not require initial fuel premix.

Excessive heat build-up during the first three hours of operation will damage
close-fitted engine parts. Do not operate at full throttle or high speeds for
extended periods during the first three hours of use. Vary the throttle openings
and vehicle speeds to reduce friction on all close-fitting machined parts, allowing
them to break in slowly without damage.

CAUTION

Never mix brands of oil. Serious chemical reactions can cause injection system

blockage, resulting in serious engine damage. Oils may also be incompatible

and the result could be sludge formation, filter blockage, and reduced cold

weather flow rates. All Polaris oils are compatible with each other.

Drive with extra caution during the break-in period. Perform regular checks on
fluid levels, lines, and all other important areas of the snowmobile.

DRIVE BELT BREAK-IN

The break-in period for a new drive belt is 30 miles (48 km). During this time,
vary the throttle position under 50% and limit full throttle use.
New drive belts should be washed with warm, soapy water and allowed to air dry
prior to use.
Always take time to warm up the belt and driveline prior to operating the
snowmobile. Free the track and skis from the ground before engaging throttle.

TRACK BREAK-IN

It is very important to inspect and adjust track tension after every ride for the first
150 miles (240 km) of use to ensure the proper tension during the break-in
period. Aggressive riders in certain snow conditions may need to adjust track
tension as early as 20 miles (32 km). After the break-in period track tension
should be inspected every 150 miles (240 km).

IMPORTANT

Track tension must be kept at specification – neither too loose nor too tight.

Overly loose track tension is inefficient and overly tight tension causes

premature wear or drive train system failures.

141

SNOWMOBILE BREAK-IN

NOTICE

Ratcheting occurs when the drive shaft drivers slip on the track. A ratcheting

event typically produces extreme vibration and is often experienced when the

track is subjected to heavy loads.

Early wear can be caused by two conditions – improper track tension and/or
sustained trail riding at high speeds without scratchers. Neither condition results
from a defect in the track, and wear caused by either or both of these conditions
is not covered by warranty.

Loose tracks reduce drive system efficiency because:

• Track tension constantly varies on snowmobiles as the rear suspension

extends and compresses.

• Loose track tension increases the chance for the drive shaft to ratchet in high

load driving modes. Track ratcheting may damage the track and drive nubs.

• Loose track tension decreases rail slider life and can cause uneven slider

wear.

• The slack in a loose track bows out in front of the rail tips. This bowing effect

significantly reduces drive system efficiency, creates drag, and changes the
approach angle of the rear suspension, which decreases the snowmobile's
ability to get on top of the deep snow.

142

SNOWMOBILE BREAK-IN

MAINTENANCE

EMISSION CONTROL INFORMATION

Any qualified repair shop or qualified person may maintain, replace, or repair the
emission control devices or systems on your snowmobile. An authorized
POLARIS dealer can perform any service that may be necessary for your
vehicle. POLARIS also recommends POLARIS parts for emissions related
service, however equivalent parts may be used for such service. It is a potential
violation of the Clean Air Act if a part supplied by an aftermarket parts
manufacturer reduces the effectiveness of the vehicle's emission controls.
Tampering with emission controls is prohibited by federal law.

EMISSION CONTROL LABEL

Your snowmobile is equipped at the time of sale with an emission control
information (ECI) label and a factory-installed emissions information hangtag.
These items are required by U.S. Environmental Protection Agency regulations.
The ECI label is permanently affixed to either the right side of the tunnel or the
engine recoil cover. The ECI label should not be removed, even after you
purchase the snowmobile. You may remove the factory-installed emissions
information hangtag, which is intended solely for your use in making a
purchasing decision.

EMISSION CONTROL MAINTENANCE
REQUIREMENTS

Your snowmobile is certified to operate on gasoline with a minimum octane level
of 87 (R+M)/2. If your snowmobile is equipped with a check engine light and it
comes on, you must take your snowmobile to an authorized POLARIS dealer for
diagnostic service. Specifications and adjustments for engine tune-ups are
located in the Service Manual, which is available to your qualified service
technician. Reverse (if equipped) must not be engaged during engine tune-ups.

OWNER'S RESPONSIBILITIES

Please read the Snowmobile Engine Emissions Limited Warranty, and read the
maintenance section of your owner's manual. You are responsible for ensuring
that the specified maintenance is performed. POLARIS recommends that you
contact an authorized POLARIS dealer, or other qualified person, to perform any
service that may be necessary.

NON-IONIZING RADIATION

This vehicle emits some electromagnetic energy. People with active or
non-active implantable medical devices (such as heart monitoring or controlling
devices) should review the limitations of their device and the applicable
electromagnetic standards and directives that apply to this vehicle.

143

MAINTENANCE

POLARIS RECOMMENDED MAINTENANCE
PROGRAM

NOTICE

Hot components can cause damage to plastic. Always make sure the exhaust

system and engine have cooled before tipping the snowmobile on its side for

service or inspection.

To ensure many trouble-free miles of snowmobiling enjoyment, follow
recommended regular maintenance and perform service checks as outlined in
this manual. Record maintenance and service in the Maintenance Log beginning
on page 239.

The recommended maintenance schedule on your snowmobile calls for service
and maintenance inspections at 150 miles (240 km), 500 miles (800 km), 1000
miles (1600 km), and 2000 miles (3200 km). These inspections should be
performed by a qualified service technician. For continued optimum
performance and component life, continue maintenance checks at 1000 mile
(1600 km) intervals.

All necessary replacement parts and labor incurred, with the exception of
authorized warranty repairs, become the responsibility of the registered owner.

If, during the course of the warranty period, part failures occur as a result of
owner neglect in performing recommended regular maintenance, the cost of
repairs are the responsibility of the owner.

Personal safety is critical when attempting to service or make adjustments to
your snowmobile. If you're not familiar with safe service or adjustment
procedures and the use of tools, or if you don't feel comfortable performing
these tasks yourself, your authorized POLARIS dealer can provide any needed
service.

WARNING

Take precaution and wear appropriate PPE (gloves and safety glasses) when

servicing or inspecting areas under the hood, exhaust components, chassis

components, or rear suspension components for any items that could be

sharp.

144

MAINTENANCE

PRE-SEASON MAINTENANCE

The chart below outlines inspection procedures that should be performed before
the start of each riding season.

Air Box

Inspect or Adjust

Bogie / Wheel Condition /
Fastener Bolts

Inspect or Adjust

Brake Fluid Level / Leaks /
Fluid Condition

Inspect or Adjust

Brake Hose Condition /
Routing

Inspect or Adjust

Brake Lever

Inspect or Adjust

Brake Pads / Brake Disc

Inspect or Adjust

Clutch Alignment / Offset

Inspect or Adjust

Controls

Inspect or Adjust the following:

• Auxiliary Shut-Off
• Ignition Switch
• Headlights / Brake light / Taillights
• Hand / Thumbwarmers

Coolant Level

Inspect or Adjust

Cooling Hoses / Pipes

Inspect or Adjust

Drive / Driven Clutch
Condition

Inspect or Adjust; Clean if needed

Drive Belt Condition / Ride
Out

Inspect or Adjust

Drive Chain Tension (If
Equipped)

Inspect or Adjust

Engine Mounts

Inspect or Adjust

Exhaust Pipe / Retaining
Springs

Inspect or Adjust

Front / Rear Suspension
Mounting Bolts

Inspect or Adjust

145

MAINTENANCE

Front Limiter Strap

Inspect or Adjust

Fuel / Vent Hoses

Inspect or Adjust

Hood / Seat / Chassis /
Engine Compartment

Clean if needed

Oil Hoses

Inspect or Adjust

Rail Slide Condition

Inspect or Adjust

Rear Idler Wheel Bolts /
Adjuster Bolt Jam Nuts

Inspect or Adjust

Shocks / Springs

Inspect or Adjust; Lubricate if needed

Ski Fasteners

Inspect or Adjust; Clean if needed

Ski Skags

Inspect or Adjust

Ski Toe Alignment /
Handlebar Centering

Inspect or Adjust

Steering Fasteners /
Linkage / Handlebars

Inspect or Adjust

Throttle Lever

Inspect or Adjust

Track Alignment / Track
Tension

Inspect or Adjust

Transmission Oil

Inspect or Adjust

146

MAINTENANCE

POLARIS MAINTENANCE SCHEDULE

The intervals shown in this table are based on vehicles operated under normal
conditions.

Each interval is given in miles (kilometers). Service the components or systems
at that interval.

Continue to follow the maintenance schedule as miles/kilometers increase on
the vehicle. For example, after the 2000 miles (3200 km) service has been
completed, do the service every 2000 miles (3200 km).

Vehicles subjected to severe use must be serviced at 50% of the stated interval.
Examples of Severe Use: Immersion in mud, water, or sand, constant high RPM
use, prolonged low-speed heavy load operation, extended idle, any operation in
dusty conditions, and short trip cold weather operation.

INITIAL BREAK-IN SERVICE

FIRST 25 HOURS / ONE MONTH

Engine Oil and Filter

Change the engine oil and filter.

The break-in period consists of the first 25 hours of operation or one month.
After initial break-in oil change, perform every 115 hours / 4000 miles (6400
km) or annually prior to summer storage. Careful treatment of a new engine
and drive components will result in more efficient performance and longer life
for these components. The items outlined in this service interval only need to
be performed at the first 25 hours of operation. They do not need to be
performed every 25 hours.

Vehicles subjected to severe use must be serviced at 50% of the stated interval.
Examples of severe use include: constant high RPM use; prolonged low-speed
or heavy load operation; extended idle; short trips.

150 MILES (240 KM)

Brake Pads / Brake Disc

Inspect or Adjust

Transmission Oil

Inspect or Adjust

Rail Slide Condition

Inspect or Adjust

Ski Skags

Inspect or Adjust

Track Alignment / Track
Tension

Inspect or Adjust

147

MAINTENANCE

500 MILES (800 KM)

Brake Pads / Brake Disc

Inspect or Adjust

Transmission Oil

Replace

Rail Slide Condition

Inspect or Adjust

Ski Skags

Inspect or Adjust

Track Alignment / Track
Tension

Inspect or Adjust

1000 MILES (1600 KM)

Brake Pads / Brake Disc

Inspect or Adjust

Transmission Oil

Inspect or Adjust

Rail Slide Condition

Inspect or Adjust

Ski Skags

Inspect or Adjust

Track Alignment / Track
Tension

Inspect or Adjust

148

MAINTENANCE

EVERY 2000 MILES (3200 KM)

Brake Fluid

Replace

Brake Pads / Brake Disc

Inspect or Adjust

Transmission Oil

Inspect or Adjust

Clutch Alignment / Offset

Inspect or Adjust

Exhaust System

Inspect or Adjust

Rail Slide Condition

Inspect or Adjust

Shocks (If serviceable)

Replace oil and recharge; Rebuild if needed.

Ski Skags

Inspect or Adjust

Spark Plugs

Replace

Track Alignment / Track
Tension

Inspect or Adjust

ADDITIONAL MAINTENANCE INTERVALS

Every 4000 miles
(6400 km)

Engine Oil and
Filter

Change the engine oil and
filter.*

Transmission Oil

Replace Fluid

Engine Valve
Clearance
Inspection

Check the engine valve
clearances; adjust if necessary

Every 60 months / 5
years

50/50 Extended
Life Coolant

Replace Fluid

*Change engine oil and oil filter annually prior to summer storage.

149

MAINTENANCE

LUBRICATION

REAR SUSPENSION

Lubricate the suspension pivot shafts

with POLARIS All Season Grease at

the intervals outlined in the Periodic Maintenance Table and before seasonal
storage. When operating in heavy, wet snow conditions, lubricate every 500
miles (800 km).

Lack of lubrication will adversely affect your ride and the life of the suspension.
For more information about suspension lubrication and adjustments, see your
POLARIS dealer.

129/137 MODELS

146 MODELS

150

MAINTENANCE

ENGINE OIL

WARNING

Vehicle operation with insufficient, deteriorated, or contaminated engine oil will

cause accelerated wear and may result in engine seizure, accident and injury.

Always perform the maintenance procedures as outlined in the Periodic

Maintenance Chart.

Always check and change the oil at the intervals outlined in the Periodic
Maintenance Chart. Always use the recommended engine oil. Always change
the oil filter whenever changing oil.

Pay special attention to the oil level. A rise in oil level during cold weather can
indicate contaminants collecting in the oil sump or crankcase. Change oil
immediately if the oil level begins to rise. Monitor the oil level, and if it continues
to rise, discontinue use and determine the cause. Your dealer can assist.

OIL LEVEL CHECK

NOTICE

Check the oil level when the engine has reached an operating temperature of

at least 173 °F (78 °C). Never check the oil with the engine running.

Polaris Recommended Engine Oil

PS-4 Extreme 0W-50 Full Synthetic Engine Oil

To check the oil level, do the
following:

1. Position the snowmobile on a

level surface.

2. Start the engine. Let engine

warm to an operating
temperature of 173 °F (78 °
C) or warmer.

IMPORTANT

Checking the oil level before

the engine has reached this

temperature may result in an

inaccurate oil level

measurement.

3. Shut off engine for 10

seconds.

151

MAINTENANCE

4. Re-start engine and idle for 10 seconds.

5. Shut off the engine.

6. Remove the left side panel.

7. Remove the dipstick

and wipe it dry with a clean cloth.

8. Reinstall the dipstick until fully seated.

9. Remove the dipstick and check the oil level. Oil level is in the safe range if it

falls between the two marks on the dipstick

10. If needed, add the recommended lubricant as needed. Do NOT overfill.

11. Reinstall and tighten the dipstick.

OIL AND OIL FILTER CHANGE

WARNING

Spilled oil left on engine components or in the engine area may pose a fire

hazard. Use shop rags to clean any spilled oil. If needed, use a non-flammable

solvent on the rag to aid the cleaning process. Do not use any device such as

pressurized water or air as this may disperse the oil onto engine components

and could pose a fire hazard.

CAUTION

Engine oil is hot after use and can cause burns to skin.

Always change the oil and filter according to the intervals outlined in the Polaris
Maintenance Schedule on page 147. Replace the oil filter every time the oil is
changed.

1. Park the snowmobile on level ground, put the transmission in Neutral, and

engage the parking brake.

2. Shut off the engine.

3. Remove the left side panel.

4. Remove the drive belt. See page 172 for drive belt removal procedure.

5. Remove the driven clutch. See page 175 for driven clutch removal

procedure.

152

MAINTENANCE

6. Drain oil from the oil reservoir.

a. Hold an oil pan under the drain plug

b. Use care to keep oil from spilling onto the clutch guard or clutches.

c. Once oil is fully drained, re-install the oil bottle drain plug with a new

washer. Torque the plug to specification.

TORQUE

Oil Reservoir Drain Plug

13.27 ft-lbs (18 N·m)

7. Drain the oil from oil filter adaptor

by attaching an 0.5 in (13 mm) (internal

diameter) hose to the adaptor spigot and route to a drain pan.

153

MAINTENANCE

8. Using an oil filter wrench, partially loosen the oil filter by turning the filter

counterclockwise. This will open the flow of oil from the housing adaptor to
the drain pan.

9. Locate the crankcase drain plug

on the bottom of the crankcase. The

drain plug can be accessed through the access hole in the bulkhead. Place a
drain pan below the plug.

10. Remove the sump drain plug and sealing washer.

11. Once oil is fully drained, re-install the drain plug with NEW washer and

torque to specification.

TORQUE

Engine Sump Drain Plug

13.27 ft-lbs (18 N·m)

12. When the oil filter adaptor has drained completely, remove the filter and

clean the filter sealing surface with a clean dry cloth.

13. Lubricate the O-ring on the new filter with a film of fresh engine oil. Ensure

the O-ring is in good condition before installing.

14. Twist the new filter into place and turn by hand until filter O-ring contacts the

sealing surface, then tighten with an additional ¾ turn.

15. Remove the hose from the oil filter adaptor.

154

MAINTENANCE

16. Fill the oil reservoir with the Polaris recommended engine oil.

FLUID CAPACITY

Recommended Engine Oil

PS-4 Extreme 0W–50 Full Synthetic 4-Cycle Engine Oil

Total System Capacity

4 qt (3.78 L)

17. Start the engine.

18. Ensure there are no leaks from the reservoir, sump drain plug, or oil filter

adaptor.

19. Stop the engine.

20. Check the oil level. See page 151 for oil level check procedure.

21. Re-install the driven clutch.

22. Re-install the drive belt. See page 172 for belt installation procedure.

23. Re-attach the left side panel.

155

MAINTENANCE

SIDE PANEL AND HOOD

CAUTION

The hood and side panels of the snowmobile protect the operator from moving

parts. Never operate a snowmobile with the hood or side panels open or

removed. Always ensure that the hood and side panels are securely in place

before starting the engine

SIDE PANELS

To open a side panel, rotate the three
1/4-turn fasteners on the outer edges of
the side panel. To remove an open side
panel, pull the panel outward to release
the tabs at the lower edge of the panel.

HOOD

To remove the hood, do the following:

1. Remove the left and right side panels.

2. Rotate the 1/4 turn fasteners

at the rear corners if the hood.

3. Disconnect the hood wire harness connector

4. Remove the hood assembly from the vehicle.

NOTE

Store the hood in a position that will not damage the brake cooler duct.

156

MAINTENANCE

INTAKE SCREENS

The intake screens

limit snow

ingestion into the intake system. When
operating in loose powder snow, check
the filters periodically to remove any
accumulation of snow or ice.

FUEL PUMP

All fuel pump service must be performed by an authorized POLARIS dealer. Do
not attempt to service the fuel pump.

FUEL PUMP PRIME PROCEDURE

The fuel injection system must be purged of air:

• If the fuel system was run out of fuel
• If the fuel system has been disassembled

IMPORTANT

Make sure there is at least 2 gallons (7.6 liters) of fuel in the fuel tank.

1. Start with vehicle key in OFF position.

2. Turn vehicle key to ON position without cranking.

3. Cycle the throttle lever five times within 5 seconds to open throttle.

4. Turn vehicle key to START. Crank until vehicle starts or 20 seconds have

passed.

IMPORTANT

Turning vehicle key to OFF position will restart the procedure.

5. If vehicle fails to start, repeat Steps 1–4 up to four times.

NOTICE

Contact your authorized POLARIS dealer f the engine does not start after

repeating this procedure four times.

157

MAINTENANCE

FUEL FILTER / FUEL LINES

This snowmobile is not equipped with an in-line fuel filter. The fuel pump uses a
sock-type pickup filter located within the fuel tank. This filter should only require
maintenance if debris or foreign material enters the fuel tank. An authorized
POLARIS dealer can provide service.

Contaminated or poor quality fuel may shorten the life of fuel system
components and result in poor engine performance. Always store fuel in clean
fuel containers. If low fuel pressure or reduced engine performance occurs, the
filter may need replacement. An authorized POLARIS dealer can assist.

Inspect the fuel lines regularly for signs of deterioration or damage. Always
check fuel line condition after periods of storage. Normal deterioration from
weather and fuel compounds may occur. Replace worn or damaged fuel lines
promptly.

NOTICE

Kinking the fuel lines or using a pliers or similar tools to remove fuel lines may
cause damage to the lines. If a fuel line has been damaged or kinked, replace

it promptly.

158

MAINTENANCE

SPARK PLUGS

SPARK PLUG RECOMMENDATIONS

NOTICE

Using non-recommended spark plugs can result in serious engine damage. A

spark plug with a heat range too high will always cause engine damage if the

engine is operated in conditions more severe than intended for that plug.

Always use the spark plugs recommended for your snowmobile.

A new engine can cause temporary spark plug fouling due to the preservative
added during the assembly process. Avoid prolonged idle speeds, which cause
plug fouling and carbonization.

Refer to the Specifications chapter for the specific spark plug to be used in your
snowmobile.

Change the spark plugs at the intervals outlined in the Periodic Maintenance
section.

• Use recommended spark plugs with the proper gap. Refer to the

specifications section for the specific spark plug to be used in your
snowmobile.

• Use only resistor-type spark plugs.
• Torque spark plugs to specification.
• Always carry spare spark plugs.

Polaris Recommended Spark Plug

NGK® 95897 MR7F

PN: 3022662

TORQUE

Spark Plug

8.8 ft-lbs (12 N·m)

159

MAINTENANCE

SPARK PLUG MAINTENANCE

Inspect and replace the spark plugs as outlined in the periodic maintenance
table.

CAUTION

Never inspect or replace the spark plugs while the engine is running or warm.

Hot engine parts can cause burns. Ensure engine is fully shut down and allow

adequate time for the engine to cool.

The spark plugs can be serviced by using the following procedure. Tools needed
for this procedure can be found in tool kit provided with your snowmobile.

1. Remove the side panels and hood assembly.

2. Use the torx wrench from the tool kit to remove the screws

from each of

the spark plug coils.

3. Pull upward on the spark plug coils

to remove.

4. Clean the plug area so no debris can fall into engine when plug is removed.

5. Use the spark plug wrench to unscrew the plugs by turning the wrench

counter-clockwise. Once loose, remove plugs from engine.

TIP

If experiencing difficulty removing the spark plugs, re-insert the coil into the

hole until it secures to the loose plug. Pull upward to remove.

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Replace the spark plug if the following is observed:

• Insulator is damaged or cracked.
• Insulator is fouled.
• Regular replacement interval has been reached as indicated in the

maintenance table.

When inspecting a spark plug, take note of the insulator color. A light brown or
dark tan color indicates the engine is running properly. If the spark plug insulator
is white, the engine may be running lean. Inspect the engine, throttle body boots,
etc. for air leaks.

If the spark plug insulator is black, oily, or shows heavy soot, the engine may be
running rich. Inspect the engine, fuel system, and lubrication system for
problems.

Set the electrode gap to specification before installing a new spark plug.

MEASUREMENT

Spark Plug Gap Range

0.027 - 0.031 in (0.7 - 0.8 mm)

When installing the spark plug, ensure it is clean and dry. Torque to
specification.

TORQUE

Spark Plug

8.8 ft-lbs (12 N·m)

SPARK PLUG CONDITION

NORMAL PLUG

The normal insulator tip is gray, tan or light brown. There will be few combustion
deposits. The electrodes are not burned or eroded. This indicates the proper
type and heat range for the engine and the service.

TIP

The tip should not be white. A white insulator tip indicates overheating, caused

by use of an improper spark plug or poor engine performance.

FOULED PLUG

There are three possible causes of a fouled spark plug:

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•

Wet Fouled Plug

: Plug will be visibly wet and smell of fuel. A wet fouled plug

is caused by an overly rich fuel mixture in combustion chamber. The plug may
be reused if dried completely.

•

Carbon / Soot Fouled Plug

: Insulator tip of plug will appear black. A carbon

or soot fouled plug is caused by extensive light load usage, extended short
trip driving, weak ignition system, among other causes. Replace plug.

•

Oil Fouled Plug

: Plug will have a thin layer of oil visible. A oil fouled plug is

caused by worn piston rings, valve guides and/or seals, or high oil carryover.
Replace plug.

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COOLING SYSTEM

WARNING

Do not attempt to bleed the cooling system. ProStar cooling systems require

filling via the vacuum fill method and an improperly filled coolant system may

cause damage to the water pump. See your Polaris dealer or other qualified

technician for cooling service on your snowmobile.

COOLANT

Recommended Coolant

Polaris Extended Life 50/50 Pre-Mixed Anti-Freeze

PN: 2880513 (1 gal)

Polaris recommends the use of Polaris Extended Life 50/50 Pre-Mixed
Anti-Freeze. This anti-freeze is already premixed and ready to use. Do not dilute
with water. If planning to store or operate the vehicle at temperatures lower than
-34 °F (-37 °C), greater protection may be required. An authorized dealer can
assist.

To ensure the coolant maintains its ability to protect the engine, Polaris
recommends completely draining the cooling system every five (5) years and
replacing with fresh Anti-freeze 50/50 Premix.

Any time the cooling system has been drained for maintenance or repair,
replace the coolant with fresh Antifreeze 50/50 Premix.

NOTICE

If coolant flow becomes restricted or plugged, coolant loss, air lock, or engine

damage may result.

COOLANT LEVEL

The engine coolant level is controlled by the recovery system. The recovery
system components are:

• Coolant bottle/overflow tank
• Pressure cap
• Connecting hoses
• In-bottle Thermostat

Always maintain the coolant level at or slightly above the FULL COLD mark on
the coolant bottle (when the engine is cold).

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1. Stop the engine and ensure engine is cold.

2. Remove the right side panel.

3. View the coolant level in the coolant bottle. Add coolant as needed.

NOTICE

Operating the snowmobile with insufficient coolant will result in overheating

and serious engine damage. Always maintain the coolant level as

recommended.

FLUSHING THE COOLING SYSTEM

To ensure that the coolant maintains its ability to protect the engine, Polaris
recommend that the system be completely drained every five (5) years and fresh
Antifreeze 50/50 Premix added. This service must be performed when the
engine is cold. Your authorized POLARIS dealer can check the coolant when
performing the fall tune-up on your snowmobile.

EXHAUST SYSTEM

Check the exhaust system for wear or damage at approximately 2000 miles
(3200 km). Always allow the engine and exhaust system to cool completely
before inspecting.

WARNING

Hot exhaust system parts can cause burns. Allow adequate time for the

exhaust system to cool. Never perform this procedure with the engine running.

1. Open the side panels and remove the hood.

2. Inspect the muffler and pipes for cracks or damage.

3. Check for weak or missing retaining springs or damper/support grommets.

4. Check for loose clamps on the pipe covers.

5. Reinstall the hood and side panels.

BRAKES

HYDRAULIC BRAKE INSPECTION

Inspect the brake lever reserve before each use of the snowmobile. See page
128.

Brake pads must be replaced when the brake pad material becomes thinner
than the backing plate (approximately 1/16 inch or 1.5 mm). A kit is available for
replacing brake pads. Your POLARIS dealer can assist.

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MAINTENANCE

WARNING

Brake failure during operation can result in serious injury or death. Properly

functioning brakes are vital to your safety. Be sure the brake pads do not drag

on the disc and that brake lever travel is not excessive. Always replace brake

pads when the brake pad material becomes thinner than the backing plate

(approximately 1/16 inch or 1.5 mm).

BRAKE COMPONENTS

Brake Caliper

Brake Disc

Brake Pad Material

Replace when thickness is less
than 1/16 in (1.5 mm).

EXCESSIVE LEVER TRAVEL

Hydraulic brakes are self-adjusting, but if excessive brake pad clearance
develops, bring the snowmobile to an authorized POLARIS dealer for inspection
and adjustment.

TIP

The lightweight brake discs have vent holes that may cause a high-pitched

sound during operation.

BRAKE FLUID

Replace brake fluid at least every two years with POLARIS DOT 4 high
temperature brake fluid, or an equivalent product.

WARNING

After opening a bottle of brake fluid, always discard any unused portion. Never

store or use a partial bottle. Brake fluid is hygroscopic, meaning it rapidly

absorbs moisture from the air. The moisture causes the boiling temperature of

the brake fluid to drop, which can lead to early brake fade and the possibility of

accident or serious injury.

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MAINTENANCE

WARNING

Keep the master cylinder cover free of dirt and debris. The vent slits allow for

diaphragm movement, and if they become plugged, movement of brake fluid

below the diaphragm may be restricted, altering brake function.

NOTICE

Brake fluid will damage labels, paint and some plastics. Always wipe up spills

immediately.

BLEEDING THE HYDRAULIC BRAKE SYSTEM

Air in the hydraulic brake system will cause spongy brake lever action. Bleed the
system before operating the snowmobile.

WARNING

Operating the vehicle with a spongy brake lever can result in loss of brakes,

which could cause an accident and lead to serious injury or death. Never

operate the vehicle with a spongy-feeling brake lever.

CAUTION

Hot exhaust system parts can cause burns. Allow adequate time for the

exhaust system to cool. Never perform this procedure with the engine running.

During the bleeding procedure, keep the brake handle as level as possible. The
reservoir must be in this position to minimize the possibility of air entering the
system through the reservoir vent.

1. Remove the brake master cylinder reservoir cover and gasket.

2. Fill the master cylinder reservoir to 1/4-5/16 inch (.6-.8 cm) below the lip of

the reservoir opening. Reinstall the gasket and cover.

3. Slip a rubber tube over the ball of the bleeder valve and direct the flow of fluid

into an approved container.

4. Squeeze the brake lever a full stroke. Then unscrew the bleeder valve 3/4 of

a turn to release air.

5. Close the bleeder valve and release the brake lever.

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Snowmobile Polaris ProStar S4, Indy XC 129 / 137, Indy Adventure 137, Voyageur 146, Nordic Pro 146. Owner’s Manual (2024) - page 5