Volvo 740 1990 Misc Documents Brake System PDF

BRAKE SYSTEM
1990 Volvo 740
1989-90 BRAKES
Volvo - Disc
240 Series, 740 Series, 760 Series
DESCRIPTION
All models use front and rear disc brakes. Three makes of
calipers are used: ATE, Bendix (DBA) and Girling. Service brakes are
hydraulically-operated by a tandem master cylinder and vacuum power
brake unit. Each rear brake line has a pressure valve to prevent rear
wheel lock-up. Parking brake is mechanically operated, using rear
wheel disc rotor internally-mounted brake shoes.
NOTE: For information on Volvo anti-lock brake system, see
appropriate article for 740 and 760 series:
* ANTI-LOCK BRAKE SYSTEM - 1989
* ANTI-LOCK BRAKE SYSTEM - 1990
BRAKE BLEEDING
NOTE: For vehicles with ABS, see
appropriate article for 740 and 760 series:
* ANTI-LOCK BRAKE SYSTEM - 1989
* ANTI-LOCK BRAKE SYSTEM - 1990
BLEEDING PRECAUTIONS
1) On all models equipped with diagonal split hydraulic
system, bleed either rear wheel first, then opposite front. Repeat
procedure on other side (circuit).
2) On all models equipped with load sensing proportioning
valve, bleed valve before bleeding brakes. If master cylinder is
equipped with a bleed screw, bleed it first.
MANUAL BLEEDING
1) Exhaust vacuum from power unit by depressing brake pedal
several times.
2) Fill master cylinder. Install a clear vinyl bleeder hose
onto first bleeder valve to be serviced. See the BLEEDING SEQUENCE
table below. Place other end of hose in clean transparent container.
3) Partially fill container with clean brake fluid so end of
hose is submerged in fluid. Open bleeder valve 1-2 turns. Slowly
depress brake pedal through its full travel.
4) Close bleeder valve and release pedal. Pump pedal several
times and push air toward wheel cylinders. Repeat procedure until flow
of brake fluid is clear and shows no sign of air bubbles. Proceed to
next bleeder valve.
NOTE: Check fluid level in master cylinder frequently during
bleeding sequence.
PRESSURE TANK BLEEDING
1) Exhaust vacuum from power unit by depressing brake pedal