SECTION 4 - HYDRAULICS
3121273
– JLG Lift –
4-11
8. Carefully thread the piston on the cylinder rod hand
tight, ensuring that the o-ring and back-up rings are
not damaged or dislodged.
9. Thread the piston onto the rod until it abuts the
spacer end and install the tapered bushing.
NOTE:
When installing the tapered bushing, piston and mating end
of rod must be free of oil.
10. Assemble the tapered bushing loosely into the pis-
ton and insert JLG capscrews (not vendor cap-
screws) through the drilled holes in the bushing and
into the tapped holes in the piston.
11. Tighten the capscrews evenly and progressively in
rotation to the specified torque value.
12. After the screws have been torqued, tap the tapered
bushing with a hammer (16 to 24 oz.) and brass
shaft (approximately 3/4" in diameter) as follows;
a. Place the shaft against the cylinder rod and in
contact with the bushing in the spaces between
the capscrews.
b. Tap each space once; this means the tapered
bushing is tapped 3 times as there are 3 spaces
between the capscrews.
13. Retorque the capscrews evenly and progressively in
rotation to the specified torque value.
14. Remove the cylinder rod from the holding fixture.
15. Place new guide locks and seals in the applicable
outside diameter grooves of the cylinder piston.
16. Position the cylinder barrel in a suitable holding fix-
ture.
NOTICE
EXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THE CYL-
INDER ROD, HEAD, AND PISTON. AVOID PULLING THE ROD OFF-
CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON AND
CYLINDER BARREL SURFACES.
17. With the barrel clamped securely, and while ade-
quately supporting the rod, insert the piston end into
the barrel cylinder. Ensure that the piston loading o-
ring and seal ring are not damaged or dislodged.
18. Continue pushing the rod into the barrel until the cyl-
inder head gland can be inserted into the barrel cyl-
inder.
19. Secure the cylinder head gland using the washer
ring and socket head bolts.
20. After the cylinder has been reassembled, the rod
should be pushed all the way in (fully retracted) prior
to the reinstallation of any holding valve or valves.
21. If applicable, install the cartridge-type holding valve
and fittings in the rod port block, using new o-rings
as applicable. (See Figure 4-13., 1932RS/6RS - Lift
Cylinder or Figure 4-14., 3248RS/10RS - Lift Cylin-
der).
22. Push the piston onto the rod until it abuts the spacer
end and install the attaching nut.
WHEN REBUILDING THE CYLINDERS, APPLY LOCTITE #262 TO
THE PISTON NUT, THEN TORQUE PISTON NUT. REFER TO APPLI-
CABLE CYLINDER ILLUSTRATION FOR TORQUE REQUIREMENT.
NOTE:
Reverse the procedure Steer Cylinder Piston Removal on
page 4-9 for installing the steer cylinder piston.
23. Remove the cylinder rod from the holding fixture.
24. Position the cylinder barrel in a suitable holding fix-
ture.
NOTICE
EXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THE CYL-
INDER ROD, HEAD, AND PISTON. AVOID PULLING THE ROD OFF-
CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON AND
CYLINDER BARREL SURFACES.
Head Gland
Piston Asssembly
Barrel Asssembly
Cylinder Rod
Figure 4-10. Rod Assembly Installation
