B
BRAKES
Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
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Repair and Service Manual
634756
OPTIONAL FRONT HYDRAULIC BRAKES
Front hydraulic brakes are optional, therefore may not be
present on all vehicles.
SYSTEM DESCRIPTION
To ensure correct braking performance, all periodic
maintenance, inspections and procedures must be per-
formed as indicated in the Periodic Service Schedule
section.
The brake system must be bled whenever any part of
the brake system has been replaced.
A hydraulic system is used to actuate the front brakes.
The system transmits the power required to activate the
friction surfaces (pads) of the braking system from the
pedal to the individual disc brake hubs at each wheel.
The front hydraulic brake system is designed to operate
only after significant rear brake pressure has been
applied. This occurs by activation of the master cylinder,
after the brake pedal has reached the park brake latch
position. The lower actuator pivot is connected to the
brake pedal by a linkage rod which rotates to contact the
upper actuator pivot. The upper actuator pivot is con-
nected to a clevis on the master cylinder plunger. Move-
ment of the plunger hydraulically activates the caliper
pistons, forcing the brake pads against the rotors. With
the brake pedal released, the upper actuator pivot and
the plunger returns to the ‘at rest’ position. With the mas-
ter cylinder no longer applying hydraulic pressure to the
brake pistons, the piston seals retract the pistons permit-
ting the brake pads to float freely against their guide pins
while removing all pressure against the rotors.
MASTER CYLINDER REPLACEMENT
When this procedure is preformed, it is likely that
brake fluid will leak from the master cylinder. Use
care to avoid brake fluid contact with painted body
panels. If contact occurs, wipe off immediately.
Removing the front shield may improve accessibility to
brake components. (See BODY section).
Remove Master Cylinder
Remove bolts (1) securing the brake actuator assembly
housing cover (2) and remove cover (Ref. Fig. 34).
Remove the cotter pin (3) and clevis pin (4) securing the
upper actuator pivot (5) and master cylinder clevis (6).
Remove the braided brake line (not shown in illustration)
from the master cylinder (7) and allow brake fluid to drain
into a container. Discard fluid.
Do not reuse old brake
fluid.
Remove the hardware (8) securing the master cylinder to
the brake actuator assembly housing (9).
Install Master Cylinder
Install new master cylinder, and tighten nuts to 12 - 14 ft.
lbs. (16 - 19 Nm) torque.
Install brake line to new master cylinder and tighten to 15
in. lbs. (1.7 Nm) torque.
Latch the brake pedal.
Rotate and hold the upper actuator pivot (5). Adjust mas-
ter cylinder clevis (6) until the clevis pin (4) can be
installed.
Tighten jam nut against master cylinder clevis.
Install a new cotter pin.
Bleed hydraulic system.
Add clean fresh DOT 3 brake fluid into reservoir and
bleed system per ‘BLEEDING BRAKES’.
Fig. 34 Master Cylinder Replacement
1
2
3
4
6
5
7
8
8
9