Section I. CARRIAGE AND BOOM ASSEMBLIES

TM 10-3930-634-34

CHAPTER 7

REPAIR OF CARRIAGE ASSEMBLY, BOOM ASSEMBLY, FRAME, HOOD,

AND PANELS

Section I. CARRIAGE AND BOOM ASSEMBLIES

7 - 3 . Boom Assembly

7-1. General

a. General. The boom assembly serves as an inter-

The carriage assembly and the boom assembly work to-

mediate load supporting member between the frame of

gether to form the load retrieval, lifting, and carrying

the lift truck and the carriage assembly. It also is the

members of the forklift truck. These are the members

member that provides for the extension and retraction

that do the actual lifting and portioning of the load.

of the forks, as well as the tilting of the carriage as-

The load forces are transmitted by these members to

sembly and forks.

the frame of the forklift truck.

b. Removal.

(1) Remove the carriage assembly (TM

10-3930-634-12).

7-2. Carriage Assembly

(2) Remove the boom assembly (para 2-9).

c. Disassembly. Refer to figure 7-2 and disassemble

a. General. The carriage assembly includes the forks

the boom assembly.

and is the unit that immediately contacts and carries

d. Cleaning and Inspection.

the load. It is the unit that provides for the side shift-

(1) Clean all parts thoroughly, using solvent

ing of the forks and for the immediate support of the

P-D-680 or equal.

load.

(2) Remove rust deposits with a wire brush.

b. Removal. Remove the carriage assembly (TM

(3) Inspect the inner boom for cracks, breaks,

10-3930-634-12).

c. Disassembly. Refer to figure 7-1 and disassemble

broken welds, distortion, and for worn or pitted upper

or side wear strips. These are welded to the inner boom

the carriage assembly.

and may be removed only by use of a cutting torch.

d. Cleaning and Inspection.

Wear is usually low and replacement is seldom re-

(1) Clean all parts thoroughly, using solvent

quired.

P-D-680 or equal.

(4) Inspect the outer boom for cracks, breaks,

(2) Use a wire brush to remove rust deposits.

broken welds, distortion and other damage.

(3) Inspect the carriage frame and the two arms

(5) Inspect the small components for wear, distor-

for cracks, breaks, distortion, and damaged or broken

tion and other damage.

welds.

(6) Weld cracks in the inner or outer boom. After

(4) Inspect the clevis for breaks and distortion.

welding, remove flux deposits. In areas that form a

(5) Inspect the sprockets for wear and other dam-

sliding surface, carefully grind the welds smooth.

age.

Then, inspect the welded areas with the magnaflux or

(6) Inspect the small components for wear, distor-

dye penetrant inspection process.

tion, and other damage.

(7) Replace all defective parts.

(7) Weld cracks in the carriage frame or forks.

e. Reassembly. Refer to figure 7-2 and reassemble

After welding, remove flux deposits and inspect the

the boom assembly.

welded areas with the magnaflux or dye penetrant

f. Installation.

process.

(1) Install the boom assembly (para 2-9).

(8) Replace all defective parts.

(2) Install the carriage assembly (TM

e. Installation. Install the carriage assembly (TM

10-3930-634-12).

0-3930-634-12).

Section Il. FRAME, HOOD AND PANELS

7-4. General

completed by attachment of various brackets, fittings,

counterweight, and covers, all attached with conven-

The forklift truck frame is constructed of welded steel

tional hardware. The hood and panels are provided to

channel in the conventional manner. The frame is then

7-1