Drum Brakes - Opel 1900 1973 Service Manual

1973 OPEL SERVICE MANUAL
DESCRIPTION AND OPERATION:
Description of Brake Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operation of Hydraulic Service Brake . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS:
Brake Trouble Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND ADJUSTMENTS:
Brake Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filling, Bleeding and Flushing Brake
Hydraulic System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAJOR REPAIR:
Replace or Reline Brake Shoes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspecting and Reconditioning Brake Drums . . . . . . . . . .
Brake Wheel Cylinder Overhaul . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing Brake Pipes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS:
Brake Specifications . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DESCRIPTION AND OPERATION - DRUM
BRAKES
DESCRIPTION OF BRAKE MECHANISM
Wheel Brake Assemblies
Each rear wheel brake assembly uses two brake shoes
which are actuated by a single wheel brake cylinder.
The center of the brake shoes are held against the
backing plate by a hold down pin, spring and re-
tainer. The bottom of the shoes pivot in a support
plate, and the top of the shoes rest directly on the
wheel brake cylinder push rods. The brake shoes are
connected by upper and lower return springs which
pull the sh6es back to resting position after applica-
tion. See Figure 5C-40.
Two adjusting eccentrics at each wheel provide in-
dividual adjustment for each brake shoe to obtain
clearance with. the brake drum. An arrow on the
brake backing.plate circumference,shows direction in
which eccentrics must be turned to make adjust-
ment.
A hydraulic wheel cylinder is mounted on the back-

DRUM BRAKES

CONTENTS
Subject
ing plate between the upper ends of the brake shoe
and forces the shoes against the drum when pressure
is applied on the brake pedal. A lever mounted on
each rear shoe is used for applying parking brakes.
Page No.
Figure 5C-40 Rear Wheel Brake