Pressure Relief Valve

Pressure accumulator, pressure relief valve, checking

Test condition:
- pump delivery rate OK

Work sequence

- with engine not running, press brake pedal about 20 times to reduce pressure in system




- disconnect wires on warning light switch and remove switch (arrow)




- attach pressure gauge with hollow bolt and copper washers to brake servo unit

NOTE: Attach thick copper washer between brake servo unit and banjo fitting and thin copper washer between hollow bolt and banjo fitting

- start engine and let idle until pressure gauge reads more than 140 bar (2030 psi)
- if specification Is not reached, pressure relief valve leaking, replace pressure accumulator
- recheck system pressure

- with engine not running, press brake pedal about 20 times to reduce system pressure
- remove pressure gauge
- install brake light warning switch and reconnect wire connectors
- check all connections for leaks