Brake system bleed (Brakes)

BRAKE SYSTEM BLEED

Service repair no - 70.25.02

The following procedure covers bleeding the complete system but where only the primary or secondary circuit have been disturbed in isolation, it should only be necessary to bleed that system. Partial bleeding of the hydraulic system is only permissible if a brake pipe or hose has been disconnected with only minor loss of fluid.

CAUTION:

• Never use fluid that has been bled from the brake system. • Do not allow fluid level in reservoir to fall below ’MIN’ mark during bleeding. • Do not fill reservoir above ’MAX’ level.

1. Raise front and rear of vehicle.

WARNING: Support on safety stands.

2. Check all pipe and hose connections are tight and there are no signs of leakage.
3. Top-up fluid level in brake reservoir to ’MAX’ mark. See INFORMATION, Capacities, fluids and lubricants.

CAUTION: Use only new brake fluid of the recommended grade.

4. Attach bleed tube to LH rear brake caliper bleed screw, submerge free end in a clear container containing brake fluid.
5. Apply pressure to brake pedal several times, then apply steady pressure.
6. Loosen bleed screw to release brake fluid and air. Allow pedal to return unassisted.
7. Depress brake pedal steadily through its full stroke and allow to return unassisted. Repeat procedure until a flow of clean air-free fluid is purged into container then, whilst holding pedal at end of downward stroke, tighten bleed screw to 10 Nm. Remove bleed tube.

CAUTION: Maintain brake fluid level above ’MIN’ mark during this procedure.

8. Top-up brake fluid level.

• Bleed sequence:
• LH rear to RH rear
• RH front to LH front

9. Repeat procedure at each wheel in the sequence shown.

CAUTION: Braking efficiency may be seriously impaired if wrong bleed sequence is used.

10. Remove bleed tube. Apply brakes and check for leakage.
11. Remove stand(s) and lower vehicle.
12. Road test vehicle. Check brake pedal for short firm travel when brakes are applied.