Brake Fluid, Replacement With Bleeding Unit [CCCC]
CCCC. Brake fluid, replacement with bleeding unitSpecial tools: 115 8147, 999 2809
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Replacement guidelines
Replacing brake fluid is recommended every 48,000 km (30,000 miles), or every other year. In cars where the brakes are used and often (e.g. in hilly areas or in tropical climates where humidity levels are high), fluid should be relaced each year.
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Background
The reason that brake fluid should be changed is that brake fluid is hygroscopic: that is, it absorbs water molecules from the air. Water is partly absorbed through the brake hoses and brake fluid reservoir, which are made of rubber and plastic respectively, and are to some extent permeable to water molecules. Increasing the water content of brake fluid means that the brake fluid's boiling point falls dramatically and that corrosion forms on the braking system components. The result is that the braking system is damaged and its functioning seriously impaired.
Note! Use only Volvo original brake fluid marked DOT 4+. Never re-use brake fluid.Always keep brake fluid in its original packing, well sealed.
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Preparations
Ignition off
- Jack car up and remove wheels.
- Clean around brake fluid reservoir cap.
- Remove filling cap.
- Get a drain bottle and hose to collect brake fluid in.
- Set bleeding unit to 0.2 - 0.3 MPa (29-42.7 psi).
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Connecting bleeding unit
- connect bleeding unit to brake fluid reservoir.
Follow manufacturers' instructions for connecting and using bleeding unit.
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Replacing brake fluid LH front
Remove:
- Protective cap from bleed nipple on front LH brake caliper.
Connect drain bottle hose. Open nipple approx. one turn.
- Push brake caliper piston to bottom of caliper using a bolt clamp. Leave bolt clamp in the pushed-in position.
- Pressurize braking system with bleeding unit. Drain off 2 - 3 dl (0.2 - 0.3 US qt) brake fluid.
- Close bleed nipple and remove hose.
- Re-fit protective cap.
- Depressurize braking system using the bleeding unit.
- Remove bolt clamp from brake caliper.
- Depress brake pedal a few times.
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Replacing brake fluid RH, front
- Repeat steps [CCCC3 - CCCC5], on the front RH brake caliper. Then continue as per instructions below.
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Removing brake pad LH rear
Remove:
- Brake pad from brake caliper as per KB , Service manual, TP 5001011.
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Replacing brake fluid LH rear
- Remove protective cap from bleed nipple.
- Connect drain bottle hose.
- Open nipple approx. one turn.
- Push brake caliper pistons to bottom of caliper. Use tool 999 2809 (x 2). Leave tools on calipers.
- Pressurize braking system and bleeding unit.
- Drain ~ dl brake fluid
- Close bleed nipple and remove hose.
- Re-fit protective cap.
- Depressurize braking system using bleeding unit.
- Remove tools from brake calipers.
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Installing rear brake pad
- Install brake pad as per KB , Service manual, TP 5001011.
- Depress brake pedal a few times.
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Replacing brake fluid RH, rear
- Repeat steps CCCC6 - CCCC8, on RH rear brake caliper.
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Removing bleeding unit
Remove:
- Bleeding unit connection from brake fluid reservoir.
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Finishing work
- Depress brake pedal repeatedly until brake pistons return to normal position.
- Check brake fluid level and install reservoir cap. Clean up any brake fluid spillage with lukewarm water and car-wash shampoo.
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Installing wheels
Make sure that brake disc and rim contact surfaces are clean.
- Grease hub center rim guide with anti-rust agent 116 1038-3.
Install:
- Wheel.
- Nuts hand tight. Then tighten them in a star pattern to 110 Nm (81.2 ft lb). It tightening with a nut wrench, use torque bracket 115 8147
Note! Tightening nuts in a star pattern to a specified torque is important to prevent stresses arising in the brake disc.