(6) Inspect valve spools for scoring, wear and
(2) Install new element by reversing procedure in
damage. Check valve body bore in same manner.
Check springs for loss of pressure and damage. If
spools or body are damaged, replace entire valve
6-37. HOIST CYLINDER.
(1) Remove lift chains (paragraph 6-30).
(1) Replace spools in valve body. Seat packings
in counterbore, and place packing retainers over them.
(2) Drain hydraulic tank and disconnect hydraulic
Assemble spring and washer within retainers, install over
hose from elbow at base of hoist cylinder. Cap hose to
spool, and secure with retaining ring. Install spool cap.
keep out dirt.
Repeat this procedure with corresponding parts at other
(3) Remove screws and washers which attach
crosshead to hoist cylinder. Raise crosshead free of
(2) Install packings at top of each spool, followed
by packing retainers, and wipers. Install brackets with
(4) Remove cylinder from position in bottom
member of outer upright and remove flow regulator and
(3) Place packing on check valve cap. Install
both elbows from base of cylinder.
poppet, spring and cap and packing.
(4) Press plunger seat into position, install
(1) Remove wiper ring, packing retainer, packing
plunger and poppet assembly, spring and pilot seat. Put
set and sleeve bushing from hoist cylinder.
packing on retainer and install retainer.
(2) If leakage is apparent, remove cylinder bleed
(5) Position pilot plunger, and spring.
screw and replace gasket.
packing on cap and install cap.
c. Assembly. Reverse b above, tightening packing
(6) Install setscrew, seals and nut. Install nut,
retainer (6) just snugly enough to prevent leakage.
and install handles and linkage by reversing a. above.
(1) Reverse a.above.
(1) On a hydraulic test bench, apply fluid
pressure from a source with a 3 gpm capacity, to 2000
(2) Loosen cylinder bleed screw enough to
psi, to the inlet port of the valve.
release trapped air slowly, and operate hoist cylinder
until hydraulic fluid is free of air bubble leaks from around
(2) Operate either handle to shut off flow and
screw. Tighten screw.
operate the regulator valve. Valve must relieve at 1650
to 1750 psi. To adjust, remove cap nut, loosen plain nut,
6-38. TEST AFTER INSTALLATION. Test operation of
and turn setscrew clockwise to raise setting, or
cylinder. If fluid leaks around packing, tighten packing
counterclockwise to lower setting. Tighten locknut and
retainer only enough to stop leak.
replace cap nut.
6-39. MAST AND CARRIAGE ASSEMBLY.
g. Installation. Reverse procedure in b above.
6-36. FILTER CARTRIDGES. Two filters are used in
the hydraulic system; one in suction line within the
(1) Attach a chain hoist to mast assembly (or use
hydraulic tank, the other in return line from control valve.
the forks of another lift truck), and relieve the weight of
the assembly on its supporting parts. Arrange to brace
a. Return filter cartridge replacement.
the assembly against tipping as disconnections are
made. The forks are to be fully lowered at this time.
(1) Turn cartridge from filter head by hand.
(2) Disconnect hydraulic hose from lift cylinder
(2) Install new cartridge by reversing procedure
cap hose and cylinder to exclude dirt.
in (1) above.
b. Suction filter element replacement.
(1) Refer to paragraph 6-31 b (1) and (2).
(3) Disconnect .both tilt cylinders at uprights.
(4) Remove capscrews, washers and angle
brackets which secure outer uprights to bearing bracket