JLG 1850SJ Service Manual - Manual (Page 197)

SECTION 5 - BASIC HYDRAULIC INFORMATION & HYDRAULIC SCHEMATICS
3121619 – JLG Lift – 5-27
3. Install cylinder head assembly on rod. Do not damage or
dislodge wiper and rod seals. Push head along rod to
rod end.
4. Install piston spacer (20) on rod.
5. Install backup ring (18), O-ring (19) and backup ring (18)
in inner diameter grooves of piston (17). Install two seals
(16) and lock rings (15) in outer grooves of piston.
6. Using suitable protection, clamp cylinder rod in a vise or
similar holding fixture as close to piston as possible.
7. Thread piston on cylinder rod hand tight. Ensure O-ring
and back-up rings are not damaged or dislodged.
NOTE: Piston and mating end of rod must be free of oil when
installing tapered bushing.
8. Thread piston on rod until it aligns with spacer end and
install tapered bushing.
9. Apply JLG Threadlocker (P/N 0100011) or equivalent to
tapered bushing capscrews and assemble the tapered
bushing loosely into the piston. Insert capscrews
through the drilled holes in the bushing and into the
tapped holes in the piston.
10. Tighten the capscrews evenly and progressively in rota-
tion to 9 ft.lbs. (12 Nm).
11. 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 con-
tact with the bushing in the spaces between the
capscrews.
b. Tap each space once; this means the tapered bush-
ing is tapped 3 times as there are 3 spaces between
the capscrews.
12. Retorque the capscrews evenly and progressively in
rotation to 9 ft.lbs. (12 Nm).
13. Install two counterbalance valves (3) with new O-rings in
valve block. Torque to 30-35 ft-lb (41-47 Nm)
15
16
17
15
18
18
19
20
Figure 5-44. Piston Seal Kit Installation
Figure 5-45. Tapered Bushing Installation
Figure 5-46. Seating the Tapered Bearing