JLG 150HAX Service Manual - Manual (Page 101)

SECTION 5 - HYDRAULICS
3120817 – JLG Lift – 5-5
Main Telescope Cylinder Removal
1. Place machine on a flat and level surface, with main
boom fully retracted and in the horizontal position.
2. Shut down engine. Support boom platform end with
a prop or overhead lifting device.
3. Remove boom end cover.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID THE ENTRY OF
CONTAMINANTS INTO THE SYSTEM.
4. Tag and disconnect hydraulic lines to telescope cyl-
inder. Use suitable containers to retain any residual
hydraulic fluid. Cap hydraulic lines and ports.
5. Remove two snap rings securing telescope cylinder
pin to base boom.
6. Using a suitable brass drift, carefully drive telescope
cylinder pin from base boom.
7. Remove telescope cylinder trunnion pin covers from
each side of boom.
8. Remove capscrews securing trunnion pins from
each side of boom.
9. Using a suitable slide hammer, remove trunnion
pins attaching telescope cylinder to mid boom.
10. Attach a suitable sling to telescope cylinder rod.
Support with an overhead crane or other suitable lift-
ing device.
11. Remove two extension chain adjusting nuts from
eye bolt through chain adjust block.
12. Remove four bolts and lockwashers attaching chain
attach block to base boom section and remove
block.
13. Using the lifting equipment, raise cylinder to obtain
sufficient clearance for removal of rod support
bracket.
14. Remove cylinder rod support bracket.
15. Attach a suitable lifting device to extension chain
adjusting eye bolt above cylinder rod.
NOTE: The extension chain will come out of the boom twice
as far as the telescope cylinder.
16. Using both lifting devices, carefully pull cylinder
from boom assembly.
17. As cylinder is removed from boom, lay extension
chain on top of base boom.
18. Using another lifting device, support sheave wheel
end of cylinder and remove cylinder from boom
assembly.
19. Carefully lift cylinder clear of boom assembly and
lower to ground or suitably supported work area.
Main Telescope Cylinder Installation
1. Using suitable lifting equipment, carefully lower cyl-
inder to boom assembly.
2. Using another lifting device, support sheave wheel
end of cylinder and install cylinder into boom
assembly.
3. Slide cylinder into boom, sliding extension chain in
place as cylinder is moving in.
4. Attach a suitable lifting device to extension chain
adjusting eye bolt.
5. Attach cylinder rod support bracket to rod support
block on telescope cylinder.
6. Install chain adjust block to base boom section with
four lockwashers and bolts.
7. Install two extension chain adjusting nuts that attach
eye bolt to chain adjust block.
8. Remove sling attached to telescope cylinder rod.
9. Using a suitable brass drift, install trunnion pins
attaching telescope cylinder to mid boom section.
10. Install capscrews securing trunnion pins to each
side of boom. Note that JLG Threadlocker P/N
0100011 is required on capscrew threads.
11. Install trunnion pin covers on each side of boom.
12. Carefully install telescope cylinder rod attach pin
into base boom.
13. Install snap rings that retain telescope rod attach pin
to base boom.
14. Remove applicable hydraulic line and port caps and
correctly connect hydraulic lines to telescope cylin-
der. Ensure all hoses are correctly routed.
15. Install boom end cover.
16. Activate hydraulic system.
17. Using all applicable safety precautions operate
boom functions. Check for correct operation and
hydraulic leaks. Secure as necessary.
18. Cycle boom several times and torque boom chains
to 50 ft. lb. (68 Nm).
19. Check fluid level of hydraulic tank and adjust as nec-
essary.