HANDBRAKE LEVER.

NOTE

(3) If required, tighten brake shoe adjusting

nut to set clearance between these valves. Don't

Plates of end links are secured by cotter pins.

overtighten, so as

Do not rivet these pins.

brake won't drag.

(4) With loaded truck held on 15 degree

Triple Mast Assembly Installation.

incline by foot brake application, raise from operator's

(1) Insert link in end of shorter chain into

seat and release foot brake. If truck rolls, stop with foot

brackets on carriage assembly. Secure link with cotter

brake and continue to (5) below.

pins in ends.

(5) Tighten spring adjusting nut (33) not over

(2) Reeve chains over rollers on outer hoist

two turns, and repeat (4) above to test results. Repeat

cylinder.

until spring application of motor brake holds loaded

(3) Secure other end of chains to anchor on

truck on 15 degree incline.

bottom of inner mast, and adjust nut to remove chain

tension (para. e.).

6-36.

SERVICE BRAKE.

(4) Insert link in end of longer chain into

a. Brake Adjustment. The service brakes are

brackets on top of inner upright. Secure link with cotter

self-adjusting to take up play due to lining wear. The

pins.

brake pedal must be adjusted for proper free pedal (para

(5) Reeve chain under rollers on bottom end

6-37b-4).

of hoist cylinder. Secure link with cotter pins.

(6) Secure chain anchors to anchor on inner

b. Bleeding Service Brake System. The hydraulic

upright with adjustment nuts and adjust chain tension

brake system must at times be bled to expel air in the

(para. e.).

system. The need is generally indicated by springy or

6-34.

HANDBRAKE LEVER.

spongy brake pedal action.

Unless special brake

bleeding equipment is available, two men are required

Removal.

to bleed the system, one to maintain a constant supply

(1) Fully release handbrake lever (18) (figure

of fluid in the master cylinder and to pump the brake

7-28) and remove screws, nuts and washers securing

pedal, the other to perform the bleeding operation.

handbrake lever to brake lever bracket (22).

(1) Remove filler plug from master cylinder

(2) Remove pin(41) from clevis (40) securing

through hole in floor plate, and fill with hydraulic brake

handbrake to seat and handbrake actuating lever (39)

fluid.

and pull handbrake lever (18) out of truck.

(2) Clean bleeder screws (22, figure 7-35) at

each wheel cylinder. Remove small screws from bore

b. Installation. Reverse procedure in a. above,

of bleeder screws. Attach one end of bleeder hose to

adjusting handbrake (para. 6-34) after installation.

bleeder screw and place other end of hose in clean

6-35.

SEAT BRAKE AND HANDBRAKE LINKAGE.

container partially filled with hydraulic brake fluid. Be

sure end of hose is submerged in the hydraulic fluid.

a. General. The parts shown in figure 7-28

(3) Turn bleeder screw counterclockwise

comprise the handbrake and seat brake linkage. These

three-quarters of a turn. Apply steady pressure to brake

parts and linkages are not subject to repair other than

pedal. Hydraulic fluid containing air bubbles should be

replacement of individual damaged parts. The parts are

forced through bleeder hose into container.

illustrated for general orientation, and to facilitate

(4) Maintain fluid level in master cylinder and

removal and installation that may be performed in

continue to operate brake pedal until fluid flows in a

conjunction with maintenance services.

steady solid stream without air bubbles. Close bleeder

screw by turning it clockwise. Remove bleeder hose

Seat Brake Adjustment.

and replace small screw in bleeder screw.

(1) Two adjustments are provided to maintain

(5) Repeat bleeding procedure at other

the motor brake at required efficiency. The brake shoe

wheel, replenishing brake fluid in master cylinder before

adjusting nuts provides the basic adjustment on which

each wheel cylinder is bled. Replace filler plug in

the seat actuation adjustment depends. The other is on

master cylinder.

the handbrake handle.

CAUTION

(2) Remove valve cover (para. 6-30) and

Hydraulic brake fluid from the brake system

floor plate (para. 6-27). With truck seat occupied and

must not be reused.

handbrake released, check with leaf or round feeler

gauge for brake shoe lining-to-drum clearance of 0.010

Brakeshoe Removal.

inch to 0.020 inch.

6-17