300Tdi Defender
70
BRAKES
4
REPAIR
PRESSURE REDUCING VALVE (PRV)
Service repair no - 70.25.21
Remove
1. Disconnect battery.
2. Clean area around reducing valve ports.
3. Place a container under valve to catch escaping
brake fluid.
4. Disconnect primary circuit pipe unions æAæ
from valve.
5. Disconnect secondary circuit pipe unions æBæ
from valve.
6. Cover pipes to prevent ingress of dirt.
7. Remove single retaining nut and bolt securing
valve to engine bulkhead.
8. Remove valve.
Refit
9. Fit valve to engine bulkhead. Tighten bolt to
15
Nm (11 lbf/ft).
10. Connect primary and secondary circuit pipes to
valve. Tighten to
16 Nm (12 lbf/ft).
11. Fill brake reservoir with recommended brake
fluid
See LUBRICANTS, FLUIDS AND
CAPACITIES, Information, Recommended
lubricants and fluids .
12. Bleed the brake system
See Brake system
bleed .
13. Reconnect battery and road test vehicle.
SERVO NON RETURN VALVE
Service repair no - 70.50.15
Remove
1. Disconnect brake vacuum hose from servo non
return valve.
2. Carefully prise 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. Do not use compressed air.
Refit
5. Fit rubber grommet.
6. Smear ribs of the valve with Lucas Girling rubber
grease to assist assembly, and push valve fully
home.
7. Connect vacuum hose to the valve.
8. Road test vehicle.
