Polaris ACE 150 EFI (2018 year). Manual - part 18

76

MAINTENANCE

Filter Systems

Air Filter

Always change the air filter at the intervals 

outlined in the Periodic Maintenance Chart 

beginning on page 57. Access the air box 

near the right rear wheel.
1. To remove the air cleaning element, 

unlatch each metal clip holding the 

cover in place.

2. Remove the air filter element.
3. Clean away any oil or sediments in the 

air box.

4. Apply a commercially available chassis 

lubricant to the inside lip of the new air filter. 

5. Install the new filter.
6. Reinstall the cover and secure the clips.

NOTICE: Never operate the vehicle with the filter element removed. Dirt will 

enter the engine, causing rapid wear and severe damage to the 

engine.

Metal clips

77

MAINTENANCE

Brakes

The front and rear brakes are hydraulic disc type brakes activated by 

the brake pedal. See page 38. 
Always check brake pedal travel and the brake fluid reservoir level 

before each use of the vehicle. When applied, the brake pedal should 

feel firm. Any sponginess would indicate a possible fluid leak or low 

brake fluid level, which must be corrected before riding. See page 79 

for brake fluid information. 
If you discover any irregularities in brake system operation, including 

excessive pedal travel, contact your dealer for proper diagnosis and 

repairs.

Operating the vehicle with a spongy brake pedal can result in loss of 

braking, which could cause an accident resulting in severe injury or 

death. Never operate the vehicle with a spongy-feeling brake pedal.

78

MAINTENANCE

Brakes

Brake Inspection

1. Check the brake system for fluid 

leaks.

2. Check the brake pedal for excessive 

travel or a spongy feel. 

3. Check the brake pads for wear, 

damage and looseness.

4. Inspect the brake pad wear surface 

for excessive wear.

5. Change pads when the friction 

material is worn to 1 mm (.04”).

6. Check the surface condition of the 

brake discs. Measure the thickness of 

the front and rear discs. Replace a 

disc if the thickness is less than 2.5 mm (0.1”).

7. Check brake system hoses and fittings for cracks, deterioration, 

abrasion and leaks. Tighten any loose fittings and replace any 

worn or damaged parts.

Brake Pad

Rear Disc

Front Disc

79

MAINTENANCE

Brakes

Brake Fluid

Inspect the level of the brake fluid before each operation. If the fluid 

level is low add DOT 4 brake fluid only. See page 102 for the part 

numbers of POLARIS products.

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 severe injury.

Change the brake fluid every two years and 

any time the fluid becomes contaminated, the 

fluid level is below the minimum, or if the type 

and brand of the fluid in the reservoir are 

unknown. Access the brake fluid reservoir 

through the left front wheel well.
1. Position the vehicle on a level surface.
2. Place the transmission in neutral. Set the 

parking brake.

3. View the brake fluid level in the reservoir. 

The level should be between the maximum 

and minimum level lines. Add brake fluid 

as needed.

4. Apply the brake forcefully for a few 

seconds and check for fluid leakage around 

the fittings.

Brake Fluid 

Reservoir