PEUGEOT 504 Series 1970 Workshop Manual page 467

BRAKES
CHECKING A SERVO-UNIT
Ill - CHECKING THE MAIN VALVE
Block master-cylinder intake.
- Remove a front bleed screw and connect the
Testarc 50 instrument.
- Remove the plug
(F ).
- Bleed the instrument
(1 ),
renew the brake fluid
level
in
the reservoir.
WARNING - With the pedal at rest, there should not
be any pressure in the system (low pressure gauge re-
gistering zero). If not, then refer to the instructions at
check V.
- Free theservo-unit (five applications of the brake
pedal with the engine at rest.
- Start-up engine without accelerating.
- the pedal should not move forward more than
3m/m.
the Testarc 50 gauges should not indicate any
pressures.
If otherwise, then the servo-unit is suspect.
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