FAN SPEED DOES NOT DECREASE FROM HIGH TO LOW SPEED. (Cont) -726250303

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.

NOTE

Use drain pan to catch leaking hydraulic oil.

VISUAL INSPECTION

(1) Remove high speed fan lockout

differential pressure sensing valve

from multifunction manifold.

(2) Remove and discard three preformed

packings and four packing retainers.

(3) Push plunger inside valve with a non-

metallic probe.

(a) If plunger sticks and does not

move freely up and down, replace

differential pressure sensing valve

(Para 17-18).

(b) If plunger moves freely up and

down, differential pressure

sensing valve is OK.

(4) Lubricate three preformed packings

and four packing retainers with

hydraulic oil and install on differential

pressure sensing valve.

(5) Install high speed fan lockout

differential pressure sensing valve.