Figure 4-47. Brake System Bleeding

TM 10-3930-633-12

Figure 4-47. Brake System Bleeding

(3) Bleed hydraulic system as required to

4-79. Brake Adjustment

remove entrapped air.

a. Front Wheels. When the brake drums are

(4) At each wheel, adjust each brake shoe in

hot, allow to cool, then proceed as follows:

turn, taking a forward acting shoe first.

(1) Adjust brake pedal free play to of

(a) Rotate the shoe (toe) adjusting cam

an inch.

until the shoe drags. A forward acting shoe cam

(2) Raise tractor until steer wheel tires clear

rotates forward; a reverse acting shoe cam rotates

floor. Be sure tractor is properly supported and

in reverse. See figure 4-48.

blocked.

(b) Back off the shoe (toe) adjusting cam,

WARNING

while rotating the drum forward, until the shoe is

After raising machine and before making

just free of drag. Operate the pedal several times

any adjustments, adjustment checks or

to center the shoes, then provide a running

before performing any maintenance,

clearance by again backing off the cam 1/8 to 1/4

place adequate blocking (sufficient to

of a turn.

support the machine) under the frame to

(5) Remove blocking, lower vehicle to the

prevent accidental lowering or falling of

floor and test the brakes.

the vehicle, thus preventing personal

injury to mechanic or bystanders.