Power Brake Assist: Service and Repair

Component Notes And Information

NOTE:
^ Brake master cylinders can no longer be disassembled for repair.
^ Use only fresh, unused brake fluid.
^ Note the labeling on the brake fluid reservoir.
^ Brake master cylinders and brake boosters are supplied by various manufacturers, but they are interchangeable.
^ Complete brake master cylinders and brake boosters can be replaced independently.

1 Clip
- Always replace
- Place on bolt
2 Lock Nut
- Tighten after adjusting clevis
3 Pin
- Install in clevis
4 Grommet
- Install in clevis
- Install spring in grommet
5 Clevis
- Adjusting, refer to: Fig. 1, below.
6 Seal
- Always replace
- Attach to intermediate mount before installing brake booster
- Roll onto bulkhead after brake booster is installed
7 Hex Nut
- Tighten to: 20 Nm (15 ft lb)
8 Intermediate Mount
9 Seal
- Install in intermediate mount
10 Brake Booster
- Diameter: 10 inch
- If necessary, replace as complete unit
- With additional vacuum booster -28- for automatic transmission vehicles
- Checking:
With engine stopped, firmly depress brake pedal several times to dissipate vacuum
Hold brake pedal down with moderate pressure and start engine
- If brake booster is OK, brake pedal will drop noticeably (with booster in effect)
11 Filler Cap
12 Gasket
- Install in cap
13 Strainer
14 Brake Fluid Reservoir With Brake Fluid Level Sensor
- Fill brake fluid up to "Max" mark
- Before topping off with brake fluid, refer to labeling on brake fluid reservoir
- Brake system total capacity: 0.6 liters (0.63 qt.)
- Connection for hydraulic clutch on side
- Functional check of brake fluid Level sensor as follows:
Remove yellow filler cap with brake symbol
Switch ignition on
Press on strainer by hand
- Brake warning light comes on
15 Brake Line
16 Seal
- Replace after removing brake master cylinder or brake booster
17 Sealing Plug
- Moisten with brake fluid and install in master cylinder
- Press brake fluid reservoir into sealing plug
- When replacing a steel Girling master cylinder, refer to Sealing Plug (At Transfer Tube), Replacing
18 Sealing Plug
- Moisten with brake fluid and install in master cylinder
- Press brake fluid reservoir into sealing plug
19 Brake Line
20 Brake Master Cylinder
- Diameter: 23.81 mm
- Before removing, disconnect vacuum line -23- and/or -31- from brake booster
- Remove and install carefully without tipping - misalignment will damage brake booster
- If necessary, replace as a complete unit
21 Hex Nut
- Tighten to: 25 Nm (18 ft lb)
22 Washer
23 Vacuum Line
24 Vacuum Line
- Connection for crankcase breather
25 Check Valve
- Must be possible to blow through valve in direction of arrow, but not in opposite direction
26 Vacuum Line
- Connection to throttle body
27 Vacuum Connection
- Connection for Air Conditioning
28 Vacuum Booster
- Increases vacuum
29 Vacuum Line
- Connection to intake manifold
30 Vacuum Line
- Not applicable for models with automatic transmission
31 Vacuum Line
- Connection to brake booster
- Not applicable for models with automatic transmission
32 Check Valve
- Not applicable for models with automatic transmission
33 Vacuum Line
- Connection for Air Conditioning
- Not applicable for models with automatic transmission
34 Vacuum Line
- Connection to intake manifold
- Not applicable for models with automatic transmission

Procedures





Fig. 1 Adjusting Clevis
- Dimension a = 223.0 ± 0.5 mm (8.78 ± 0.020 inch)

NOTE:
^ While measuring, the clevis must be at a right angle to the surface of the brake booster
^ Measure without gasket.