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Adjusting

Brake Pressure Regulator, Adjusting

Work sequence

Car must be empty
Car must be on wheels (Bosch ramp)
Fuel tank full

- remove bleeder screw and connect adaptor to left front wheel brake caliper and right rear wheel brake cylinder
- connect gauge
- bleed both hoses and gauges with bleeder valve on gauges

- have person (approximately 165 lbs) sit on driver's seat
- bounce car several times at rear
- depress brake pedal firmly several times





- depress brake pedal until gauge on front axle reads 50 bar (725 psi)
- gauge for rear axle cylinder must read 32.5 - 42.5 bar (471 - 616 psi)

- increase brake pedal pressure until gauge on front axle reads 100 bar (1450 psi)
- gauge for rear axle cylinder must read 54.0 - 71.5 bar (783 - 1037 psi)


- if pressure at rear axle is too high, release spring tension by loosening and moving bolt

- if pressure is too low, tighten spring tension

CAUTION: Do not adjust pressure regulator with brake pedal depressed

use following test sequence:

- take pressure readings
- release brake pedal
- adjust spring
- depress pedal again
- take pressure readings

- if pressure cannot be adjusted replace regulator
- disconnect pressure gauges and bleed brakes