Defender 90 (LD) V8-4.0L (1997)
Vacuum Brake Booster Check Valve: Service and Repair
Brake Booster Non-Return Valve
Removal
1. Locate servo non-return valve connection, then disconnect brake vacuum hose from servo non-return valve.
2. Carefully pry valve out with a screwdriver blade between valve and grommet. Take care not to exert too much pressure on the vacuum chamber.
3. Remove rubber grommet but be careful not to allow it to fall into the vacuum chamber.
4. Check the valve for correct operation; it should not be possible to pass air through into the servo in direction of arrow.
CAUTION: Do not use compressed air.
INSTALLATION
1. Install rubber grommet.
2. Smear ribs of the valve with Lucas/Girling grease, or equivalent, to assist assembly, then push valve fully home.
3. Connect vacuum hose to the valve.
3. Road test vehicle.