Examination
Caution: The hydraulic booster may look wet due to excess hydraulic fluid when installed at the factory or if brake fluid is spilled while filling the system. Before deciding to replace the amplifier, check its tightness.
Note: The hydraulic brake system uses two different and incompatible fluids. The hydraulic brake booster uses fluid for the power steering system. The rest of the system uses brake fluid. When servicing, do not confuse fluids.
1. Check the condition of the working fluid in the power steering system, if necessary, adjust the fluid level.
2. Clean parts of the amplifier:
- housing near fittings (3) and fittings;
- place (2) installation on the amplifier of the main brake cylinder;
- end cap;
- place (1) mounting the amplifier on the end cap.
Caution: The assistance of an assistant may be required to correctly diagnose leaks.
3. Start the engine and warm up the fluid in the power steering system to operating temperature.
4. With the engine idling, slowly depress the pedal until the power steering pump pressure reducing valve is activated (a hissing sound occurs). Hold the pedal in this position for approximately two seconds and release the brake pedal.
5. Let the engine idle for 15 seconds without depressing the brake pedal.
6. Repeat steps 4 and 5 four more times.
7. With the engine idling, turn the steering wheel from lock to lock four times, holding the wheel on each stop for 2 seconds.
Attention: do not hold the steering wheel on the stop for more than three seconds, you can overheat the working fluid.
8. Bring the engine to a speed of about 1000 rpm and turn the steering wheel from lock to lock six times at a speed of one revolution per second. Do not hold the steering wheel on the stop.
9. Let the engine idle for 30 seconds without depressing the brake pedal.
10. While the engine is idling, depress the brake pedal until the power steering pump pressure reducing valve operates, hold the pedal for one second and release the pedal. _
11. Repeat steps 7-10 four times.
12. Move the engine to idle and turn it off after 30 seconds.
13. Inspect the hydraulic booster for leaks.
Attention:
- On low mileage vehicles, a light film of liquid may form between the booster and the end cap. If a drip leak appears, replace the amplifier.
- Leakage between the brake booster and brake master cylinder is not acceptable. If there is liquid at the connector, determine the type of liquid. If it is power steering fluid, replace the brake booster. If it is brake fluid, there is a problem with the brake master cylinder.
Removal and installation
1. Apply the parking brake and block the wheels.
2. Disconnect from the amplifier of brakes an inlet hose, a hose of the steering mechanism and a returnable hose.
3. Turn away nuts of fastening of the brake cylinder to the amplifier, take the main cylinder aside.
Attention: do not disconnect the brake pipes from the master brake cylinder.
4. Remove the brake light switch.
5. Turn away four nuts of fastening of the amplifier to a partition of a motor compartment. Tightening torque 33 Nm.
6. Remove the amplifier.
7. Remove the booster gasket.
8. Install in reverse order.
9. After installation, bleed the power steering system.