Repair. - TM-10-3930-622-140118

(3) Disconnect inlet (upper) radiator hose and

(1) Loosen generator adjusting strap bolt.

outlet (lower) radiator hose secured with clamps.

(2) Loosen generator mounting bolts securing

(4) Disconnect transmission

cooling

lines

generator to mounting support and remove belt from

secured with clamps and cap the lines.

generator and crankshaft pulleys.

(5) Remove four screws, nuts, lockwashers and

(3) Work fan belt over fan blade and rotate fan

flat washers securing radiator. Lift radiator from truck.

until belt can be removed from the fan.

c. Inspection and external cleaning.

(4) Remove bolts and lockwashers that secure

fan to hub. Remove fan.

(1) Raise the hood.

(5) Drain radiator.

(2) Clean dirt, insects, and trash from the

exterior of the core, using compressed air or a stream of

(6) Disconnect bypass tube at water pump and

water applied carefully from the engine side of the core.

at thermostat elbow and remove from engine.

(3) If the core fins are bent, use a piece of wood

(7) Loosen outlet (lower) radiator hose clamp

or a blunt instrument to straighten them. Be careful not

and separate hose from water pump.

to puncture the tubes.

(8) Remove mounting nuts and lockwashers,

(4) Inspect radiator mounts and tighten them as

remove adjusting strap capscrews, and remove water

necessary.

pump and gasket from engine block.

(5) Be sure radiator hose clamps are tight.

b. Inspection.

(1) Inspect the pump for secure mounting.

(6) Inspect radiator and hoses for leaks.

(2) Inspect the water pump bearing for noise.

d. Repair.

(1) Repair leaks by soldering.

(3) Inspect the fan for secure mounting, bent or

cracked blades.

(2) If radiator core is clogged with deposits which

do not respond to cleaning solution, unsolder upper and

(4) Inspect the fan belt for wear, frays, and

lower tanks , and rod out each water passage in core

proper adjustment of 1/2-inch finger-pressure deflection

with a length of welding rod. Take care not to puncture

at midpoint between the crankshaft pulley and the fan

core, which is made of thin, soft metal. Resolder upper

pulley.

and lower tanks to core and test radiator for leaks.

c. Adjustment of belt. Refer to paragraph 5-57.

(3) Carefully straighten any bent or damaged

core cooling fins.

d. Installation. Reverse procedure in a. above and

replace gasket.

e. Draining and refilling.

(1) To drain cooling system, remove radiator cap

6-65. THERMOSTAT AND ELBOW.

and open drain cocks in radiator and block. If the cooling

system is not to be refilled immediately, attach a notice

a. Removal.

on the steering wheel to warn personnel that the cooling

(1) Drain cooling system.

system has been drained.

(2) Loosen hose clamp and remove upper hose

(2) To refill the cooling system, close drain cocks

from elbow.

and add water, corrosion inhibitor, and antifreeze as

required. Operate the engine, inspect the coolant level,

(3) Remove bypass tube from truck.

and add coolant as necessary. Install the radiator cap.

(4) Remove screws and lockwashers that secure

f. Installation.

Reverse removal procedure in b.

water outlet to cylinder head and remove water outlet

above.

with thermostat and adapter. Separate thermostat and

adapter from water outlet and remove recirculating tube

6-64. WATER PUMP, FAN, AND BELT.

water outlet. Remove outlet gasket from the cylinder

a. Removal.

head.