Brake system - bleed (Brakes)

BRAKE SYSTEM - BLEED

Service repair no -

• Complete system - 70.25.02
• Primary system - 70.25.04
• Secondary system - 70.25.05

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

CAUTION: Never re-use fluid which has been bled from the brake system. Do not allow the fluid level in the master cylinder to fall so low that air can enter the system during bleeding. Check reservoir fluid level during bleeding and top-up as required. Do not fill above the MAX mark.

CAUTION: Do not allow brake fluid to contact paint finished surfaces as paint may be damaged. If spilled, remove fluid and clean area with clean warm water.

Bleed

1. Raise front and rear of vehicle.

WARNING: Support on safety stands.

2. Check that all pipe and hose connections are tight and that there are no leaks in the system.
3. Top-up brake fluid reservoir. See INFORMATION, Capacities, fluids and lubricants.

4. Bleed sequence for ABS brake system: LH front to RH front. LH rear to RH rear.
5. Attach bleed tube to LH front brake caliper bleed screw.
6. Submerge free end of bleed tube in brake fluid held in a transparent container.₁₁
7. Open bleed screw /₄ - /₂ turn anti-clockwise.
8. Depress brake pedal steadily; allow pedal to return unassisted. Repeat procedure until flow of clean air-free fluid is purged to container then, whilst maintaining pedal at end of downward stroke, tighten bleed screw.
9. Check fluid level in reservoir; top up if necessary.
10. Repeat procedure at each wheel in the sequence shown.

NOTE: The braking efficiency of the vehicle may be seriously impaired if the wrong bleed sequence is used.

11. Switch on ignition then apply steady pressure to brake pedal several times; check that brake fluid warning light does not illuminate.
12. Check system for leaks.
13. Remove stand(s) and lower vehicle.
14. Road test vehicle and test brake operation is short and feels firm.