JLG 1500SJ Service Manual - Manual (Page 400)

SECTION 5 - HYDRAULICS
5-48 – JLG Lift – 3121262
ASSEMBLY
NOTE: Refer to the Seal Detail provided at the end of this
Service Manual for the particular model being ser-
viced for proper seal locations and orientations.
Improper seal orientation
will compromise perfor-
mance!
Inspect all components per above INSPECTION proce-
dure. Clean all components with a lint-free cloth. The bar-
rel should be flushed out and drained. Compressed air
may be used to blow out the barrel bore and all ports.
Lubricate all seals with hydraulic fluid prior to assembly.
HEAD GLAND ASSEMBLY
1. Install rod seal; refer to Seal Detail for proper orien-
tation.
2. Install wear rings.
3. Press in the rod wiper using a soft metal (brass or
aluminum) or nylon tool which contacts the wiper
360°. Make sure the wiper remains perpendicular to
the bore at all times.
4. Install the backup ring and o-ring with the backup
ring nearest the head gland flange.
PISTON ASSEMBLY
1. Install o-ring into groove in I.D. of piston.
2. Install one wear ring onto piston.
3. Install piston seal into central groove on piston O.D.
A clean, small cross-section o-ring or a thin elastic
band may be wrapped around seal to help stretch it
over piston.
4. Install remaining wear ring.
ROD, GLAND, PISTON ASSEMBLY
1. Lubricate I.D. of head gland assembly with hydraulic
fluid, and slide onto rod (rod wiper end first) using
caution not to damage rod wiper or seal on rod end.
2. Slide stop tube (with o-ring) onto rod. Do not scratch
rod chrome.
3. For pistons with threaded I.D., apply Loctite #7471
(Primer-T) to piston and rod threads. Allow primer to
evaporate then apply two beads of Loctite #222
Thread Adhesive axially across the threads of the
piston I.D.
4. Install piston assembly onto threaded end of rod.
Tighten piston onto rod end to 100 ft.lbs. An optional
method for tightening threaded piston is to turn until
piston bottoms out; then set in place by hitting span-
ner wrench handle with a hammer; piston should
rotate slightly while setting.
FINAL ASSEMBLY
1. Make sure all rags, etc. are removed from barrel
bore. Lubricate barrel bore and piston assembly
with hydraulic fluid. Avoid getting any oil in barrel
threads.
2. Place pad support on rod assembly before installing
into barrel. Use care to avoid damaging wear rings,
seals, and rod chrome.
3. Align rod with barrel assembly. Insert piston into bar-
rel opening. Use care to avoid damaging wear rings,
seals, and piston surface on barrel.
4. Lubricate o-ring and backup on head gland using
hydraulic fluid.
5. Align head gland with barrel assembly, position pad
support over head gland (avoid damaging the o-ring
and back-up with the pad support), and press head
gland into barrel assembly.
6. Apply a bead of Loctite #222 Thread Adhesive axi-
ally cap screw threads.
7. Screw cap screws into head gland / barrel assembly
and torque to 20 ft.lbs. (27 Nm).