Replacing the Brake Fluid (Using A Bleeding Unit)

Replacing the brake fluid (using a bleeding unit)

Guidelines for brake fluid replacement




It is recommended that the brake fluid is replaced every 45,000 km (30,000 miles), or every other year. The fluid must be replaced annually on cars driven in conditions requiring hard and frequent braking, such as driving in mountains or tropical climates with high humidity.

Background
The oil must be replaced because it is hygroscopic (the fluid absorbs water molecules from the air). This absorption of water occurs through the brake hoses and brake fluid reservoir. These components are rubber and plastic respectively and are not completely sealed against water molecules. An increased water content in the brake fluid dramatically reduces its boiling point and causes corrosion in the brake system components. This results in damage to the brake system. Braking performance deteriorates markedly.

Note! Use only Volvo Genuine Parts brake fluid (Volvo DOT 4+).Neverreuse brake fluid. Always keep brake fluid well sealed in its original packaging.

Preparations for changing, front




Switch off the ignition.
Clean around the brake fluid reservoir filler cap.

Connect the bleeding unit
See Brake system, bleeding (using bleeding unit) Brake System, Bleeding (Using Bleeding Unit).

Take out:
- a collecting bottle and hose to collect brake fluid in.
- a G-clamp.
Remove the protective cap from the bleed nipple on the brake calipers.
Connect the collecting bottle hose.

Changing the brake fluid, front




Open the nipple, approximately one turn.
Push the brake caliper piston to bottom of the caliper using a G clamp. Leave the G-clamp in pushed in position.
Pressurize the braking system with the bleeding unit.
Leave the bleed nipple open until the new brake fluid enters.
Close the nipple. Remove the hose.
Install the protective cap.
Remove the G-clamp from the brake caliper.

Remove the bleeding unit




Shut off the bleeding unit.
Depressurize the brake system by opening and closing a bleed nipple.
Remove the collecting bottle.
Remove the bleed unit connector from the brake fluid reservoir.

Finishing work





Note! Depress the brake pedal repeatedly until the brake pistons are in the normal position.

Check the brake fluid level. Install the cover.
Wash off any spilled brake fluid. Use warm water and car shampoo.

Install the wheel
See Installing wheels Service and Repair.

Preparations for replacement, rear

Take out:
- a collecting bottle and hose to collect brake fluid in
- a large pipe wrench
- a jimmy
- the bleeding unit.

Connect the bleeding unit
See Bleeding the rear brake system (with bleeding unit) Bleeding the Rear Brake System (With Bleeding Unit).

Raise the car

Remove the rear brake caliper
See Brake pads rear, replacing, B5244T5, B5254T2 Brake Pads Rear, Replacing.

Note! Do not remove the outer brake pad from the brake caliper. It is bonded to the caliper.

Press the piston into the brake caliper




Remove the brake pad from the piston.
Press the piston into the caliper using the pipe wrench.
Reinstall the brake pad on the piston.
Remove the protective cap from the bleed nipple. Connect the collecting bottle hose.

Replacing brake fluid, rear




Insert the jimmy between the brake pads (as a counterhold) to keep the piston in.
Open the bleed nipple, approximately one turn.

Pressurize the braking system using the bleeding unit
Leave the bleed nipple open until the new brake fluid enters.
Close the nipple. Remove the hose.
Reinstall the protective cap on the bleed nipple.
Remove the jimmy between the brake pads.

Install the brake caliper
See Brake pads rear, replacing, B5244T5, B5254T2 Brake Pads Rear, Replacing.

Remove the bleeding unit
See Remove the bleeding unit.

Finishing work
See Finishing work.