TM-9-2350-238-20-1

HULL AND RELATED COMPONENTS RECOVERY VEHICLE, FULL TRACKED: LIGHT, ARMORED, M578

TECHNICAL MANUAL; UNIT MAINTENANCE MANUAL

MAY 1994

TM-9-2350-238-20-1 - Page 1274 of 1364

TM 9-2350-238-20-1

F-5. BOOM WINCH HYDRAULIC SUBSYSTEM.

Functional Description.

a.

The hydraulic fluid power for the

d.

Moving the handle of the directional

operation of the boom winch is supplied by

control valve ( 1 ) in the PAY OUT position

the hydraulic power subsystem.

has the same effect as in PAY IN except

that the hydraulic fluid is routed in the op-

b.

The boom winch hydraulic subsystem

posite direction through the hydraulic motor

(9). The relief valve (5) controls the rate of

controls the power for boom winch opera-

flow in the return line and prevents free fall

tion when lifting or lowering a load.

of the load.

c .

Move the handle of the directional

e.

When the handle of the directional

control valve (1 ) in the PAY IN position to

control valve ( 1 ) is in the neutral position,

direct hydraulic fluid to release brake (7)

hydraulic fluid flows through the open

and operate the hydraulic motor (9) to

center port to the tow winch directional

retrieve the boom winch wire rope. Return

control valve.

fluid from the hydraulic motor (9) flows

through the pressure relief valve (5) and

f. When the engine is not operating or

the directional control valve ( 1 ), then to the

during hydraulic power failure, the boom

reservoir. The relief valve (4) limits

winch brake can be manually released by

hydraulic pressure when paying in to 1425

setting the brake release valve (7) to HAND

psi (9825 kPa) to protect the winch com -

PUMP PRESSURE and operating the hand

ponents from overload.

pump to lower a load.

F-10