Vacuum brake boosters are used on all models except those with diesel engines.
REMOVAL & INSTALLATION
- Remove the master cylinder.
- Disconnect the vacuum lines at the booster.
- Remove the steering column knee bolster for access to the booster mounting nuts, if necessary.
- Remove the clip securing the booster push rod to the brake pedal.
- Remove the nuts from the booster mounting studs.
- Remove the booster, spacer and gaskets from the front cowl panel.
- Reverse the removal procedure.
- Tighten the mounting nuts to 21 ft. lbs. (28 Nm).
- The remainder of the procedure is the reverse of removal.
Vacuum boosters can be checked with a vacuum gauge.
- Connect the vacuum gauge to the booster check valve with a short length of hose and a T-fitting (see illustration).
- Start the engine and allow it to idle for one minute.
- Check for vacuum at the gauge. If there is no vacuum or the reading is very low, the problem is either the booster or the check valve.
- Assuming vacuum reading is normal, clamp the hose shut between the vacuum source and the check valve.
- Stop the engine and observe the gauge. If the vacuum drops more than 1 in. (25mm) Hg within 15 seconds, the booster or check valve is at fault.
To test the check valve, proceed as follows:
- Disconnect the vacuum hose from the check valve.
- Remove the check valve and valve seal from the booster.
- With a hand-operated vacuum pump, apply 15-20 in. (381-508mm) Hg at the large end of the check valve.
- Vacuum should hold steady. If the gauge indicates vacuum loss, the check valve is faulty and should be replaced.