Polaris ACE 150 EFI (2018 year). Manual - part 16

68

MAINTENANCE

Drive Chain Lubrication

Lubricate the drive chain with POLARIS chain spray lube or an 

approved chain lube at the general lubrication interval specified in the 

Periodic Maintenance Chart beginning on page 57. Lubricate more 

often under severe use, such as in dirty or wet conditions. See page 

102 for the part numbers of POLARIS products.

NOTICE: Washing the drive chain with a high pressure washer or gasoline 

can cause premature wear and drive chain failure. Don't use a high 

pressure washer or gasoline to clean the drive chain.
Adjusting or operating the vehicle with improper rear drive chain 

slack can result in severe damage to the transmission and drive 

components. Always make sure the slack is within the stated 

specifications.

Drive Chain Slack Adjustment

1. Loosen the upper nut.
2. Turn lower nut clockwise in 1/2-turn 

increments, then turn upper nut until 

tight. Follow this procedure until 

chain is at proper tension. Chain 

should have 6 mm (1/4”) deflection.

3. Repeat these steps until chain is 

adjusted to desired fit. 

Lower Nut

Upper Nut

69

MAINTENANCE

Parking Brake Cable Freeplay Adjustment

1. Inspect and perform any needed service on the brake pads before 

adjusting parking brake cable freeplay.

2. Make sure the parking brake is NOT set (lever is DOWN).
3. Pull the brake cable back to inspect freeplay between the cable 

end and the caliper bracket. Freeplay should be 1.6 mm (1/16”).

4. To adjust freeplay, loosen the jam nut. Turn the in-line adjuster nut 

outward to decrease freeplay. Turn the adjuster nut inward to 

increase freeplay.

5. Tighten the jam nut against the adjuster nut.

Adjustment Nut

Jam Nut

70

MAINTENANCE

Parking Brake Adjustment

1. Inspect and perform any needed service on the brake pads before 

adjusting the parking brake.

2. Position the vehicle on a level surface. Place the transmission in 

neutral.

3. Carefully elevate the rear of the vehicle slightly. Use an 

appropriate lift.

4. Loosen the jam nut on the parking 

brake adjustment bolt.

5. While rotating the rear wheels by 

hand, tighten the adjustment bolt until 

significant brake drag is detected. 

Then back the adjustment bolt out 1/4 

turn, or until the wheel freely spins.

6. Hold the adjustment bolt in place and 

tighten the jam nut securely against 

the lever arm.

7. Check parking brake lever movement. Verify that the rear wheels 

rotate freely with the parking brake off (lever in DOWN position) 

and that the vehicle will not move when the parking brake is 

applied (lever in UP position).

8. Verify that the park brake lever stays in the UP position when the 

brake is fully applied.

Adjustment Bolt

71

MAINTENANCE

Spark Plug

Spark Plug Gap/Torque

NOTICE: Using non-recommended spark plugs can result in serious engine 

damage. Use POLARIS-recommended spark plugs or their 

equivalent. See page 100.

Spark plug condition is indicative of engine operation. The spark plug 

firing end condition should be read after the engine is warmed up and 

the vehicle is driven at higher speeds. Immediately check the spark 

plug for correct color. See page 71.

A hot exhaust system and engine can cause burns. Wear protective 

gloves when removing a spark plug for inspection.

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 incorrect throttle body 

adjustments.

Wet Fouled Plug
The wet fouled insulator tip is black. A damp oil film covers the firing 

end. There may be a carbon layer over the entire nose. Generally, the 

electrodes are not worn. See your dealer for throttle body adjustments

.

Electrode Gap

New Plug Torque

Used Plug Torque

0.6-0.7 mm

12-15 Nm

(9-11 ft-lbs)

23-27 Nm

(17-20 ft-lbs)