If not supported the mast will fall
6-35. LIFT AND TILT CONTROL VALVE, LEVERS
forward when the tilt cylinders are
a. Removal of levers and linkage.
(4) Remove screws attaching shafts to brackets
(1) Open engine cover and right side door for
on truck frame and on uprights.
access to control valve.
(5) Pull or drive shafts from cylinder ends. Be
(2) Remove cotter pins, links and pins securing
careful not to let cylinder fall as shafts are removed.
levers to control valve.
(3) Remove lift control levers free of valve.
(1) Remove nut, washer and screw from rod
end. Remove rod end from piston and rod.
b. Removal of lift and tilt control valve.
(1) Disconnect tube at elbow (figure 6-18) after
(2) Remove screw, washer and retainer from
draining hydraulic tank.
stuffing box. Remove wiper ring and packing. Unscrew
stuffing box from cylinder and take out piston and rod,
(2) Disconnect tee fittings at control valve.
and remove packings from piston.
(3) Loosen hose clamp and remove upper hose.
Repair of the tilt cylinders is
accomplished by installation of new parts to replace
(4) Disconnect lower hose from control valve.
defective items found during disassembly.
(5) Remove capscrews, nuts, and washers, and
remove valve from truck.
(1) Install packings on piston, and install in
cylinder. Screw stuffing box snugly into cylinder with a
(6) Remove elbows and adapters from valve.
pin spanner's wrench.
Replace them on hoses for safekeeping, as they can be
reused if not damaged. Be certain to plug or cap all
(2) Position packing in stuffing box and install
hoses to excludes dirt.
packing retainer with screws and washers only tightly
enough to prevent seepage of fluid. This item can be
further tightened later, after installation of the cylinder, if
(1) Unscrew plug and seal at bottom of relief
necessary to stop leakage.
valve. Remove cap nut, and locknut and seals on top of
relief valve. Back out setscrew and remove spring and
(3) Install wiper ring on piston rod, replace rod
pilot plunger. Remove relief valve cap and packing.
end, screw, washer and nut.
(2) Remove packing and retainer, pilot seat,
spring, poppet assembly, plunger and seat from relief
(1) Position tilt cylinder (back end) in U shaped
valve bore in body.
bracket on truck frame (figure 6-17).
(3) Remove check valve cap and packing, spring
(2) Aline bracket holes and cylinder end hole.
Insert shaft through bracket and cylinder end hole.
Secure shaft with screws.
(4) Remove screws and bracket from both TILT
and HOIST valves. Remove valve spool wipers, packing
(3) Remove plugs from ports and caps from
retainers and packing from valve body.
hoses and connect hydraulic hoses to cylinders.
(5) Take off both spool caps, and remove
(4) Check oil level in reservoir.
retaining rings, four spring retainers; springs and
(5) After installation, operate tilt control lever
several times to purge air from cylinders.
(6) Remove packing retainers and packings.
cylinders and hose fittings for leakage while operating.
Remove valve spools only for inspection and cleaning.
They are not replacement items.
Spools are not
(6) Retract both tilt pistons fully. With mast tilted
interchangeable. Replace each in its original position in
10 deg. to rear of vertical and pistons retracted fully,
repeat step (2) above. Secure front end of tilt cylinders
to upright brackets with shafts and attaching screws.