HOOK ARM DOES NOT UNLOAD. (Cont) -726250379

TM 9-2320-364-34-1

High pressure hydraulics [oil under 3675 psi (25,339 kPa) pressure] operate this equipment. Refer to

vehicle operator and maintenance manuals for hydraulic oil pressure. Never disconnect any hydraulic

line or fitting without first dropping pressure to zero. Failure to comply may result in injury to personnel.

Fuel and oil are slippery and can cause falls.

To avoid injury, wipe up spilled fuel or oil

with rags.

Do not get under LHS when disconnecting or

connecting connectors or hoses. A hydraulic

malfunction could cause LHS to lower causing

serious injury.

FLOWMETER TEST

(1) Raise hook arm completely

(TM 9-2320-364-10).

(2) Set hydraulic selector switch to

OFF position.

(3) Turn OFF ENGINE switch.

(4) Disconnect hose 2917 male quick

disconnect from LHS control box

female quick disconnect.

(5) Disconnect hose 2881 from middle

frame bulkhead.

(6) Connect adapter hose to hose 2881.

(7) Connect adapter hose to middle

frame bulkhead.

(8) Connect flowmeter IN port to

adapter hose connected to

hose 2881.

(9) Connect flowmeter OUT port to

adapter hose connected to middle

frame bulkhead.

(10) Completely open flowmeter load

valve.

(11) Connect quick disconnect

hose 2917.

(12) Start engine (TM 9-2320-364-10).

(13) Set hydraulic selector switch to

MAN HA position.

(14) With the aid of an assistant, observe

flowmeter while holding joystick in

UNLOAD position.

(a) If more than 0 gpm (0 lpm) are

present, perform Steps (15)

through (22) below and replace

LH cylinder (Para 17-12).

(b) If 0 gpm (0 lpm) are present,

cylinder is OK.

(15) Set hydraulic selector switch to OFF

position.

(16) Turn OFF ENGINE switch.

(17) Disconnect hose 2917 male quick

disconnect from LHS control box

female quick disconnect.

(18) Disconnect flowmeter from two

adapter hoses.

(19) Disconnect adapter hose from

middle frame bulkhead.

(20) Disconnect adapter hose from

hose 2881.

(21) Connect hose 2881 to middle

frame bulkhead.

(22) Connect quick disconnect

hose 2917.

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