JLG E300 Service Manual - Manual (Page 115)

SECTION 5 - HYDRAULICS
3120772 – JLG Lift – 5-19
4. Tag, disconnect and cap the lift cylinder hydraulic
lines and ports.
5. Remove the hardware securing the barrel end attach
pin #6 to the boom. Using an appropriate brass
drift, drive out the cylinder barrel pin #6.
6. Carefully remove cylinder from boom. Place in a
suitable work area.
Lower Lift Cylinder Installation
NOTE: Coat I.D. of bushings with specified lubricant prior to
installing pins.
1. With the Tower positioned and supported as in Fig-
ure 5-1., place cylinder in position and secure in
place using slings.
2. Install the cylinder barrel pin #6, being sure to align
the hole in the cylinder barrel pin with the retaining
pin screw hole. When holes align, install hardware.
3. Correctly install hydraulic lines to cylinder as previ-
ously tagged. Extend cylinder rod slowly until attach
pin hole aligns with those in boom.
4. Using a suitable brass drift, drive the cylinder rod
attach pin #5 through the aligned holes. Secure the
pin in place using retaining hardware.
5. Remove boom prop and overhead crane. Take the
lift cylinder through one complete cycle to assure
correct functioning. Place boom in stowed position.
Check hydraulic fluid and adjust accordingly.
Upper Boom Telescope Cylinder Removal
1. Place machine on flat and level surface, with Upper
Boom in the horizontal position. Extend Upper
Boom until fly attach pin #1 is accessible on fly.
2. Support Upper Boom basket end with a prop. Sup-
port Upper Upright end with an overhead crane.
3. Tag, disconnect hydraulic lines to telescope cylinder.
Use suitable container to retain any residual hydrau-
lic fluid. Cap hydraulic lines and ports.
4. Remove the retaining rings that retain the telescope
cylinder rod to the fly boom.
5. Using a suitable brass drift, carefully drive the tele-
scope cylinder rod pin #1 from the fly boom.
6. Remove the four (4) bolts securing the telescope
cylinder barrel end to the base boom.
NOTE: Care should be taken when removing the telescope
cylinder, do not leave cylinder rest on powertrack
which could cause damage to powertrack.
7. Using a suitable brass drift, carefully drive the tele-
scope cylinder pin from the base boom.
8. Attach a suitable sling to the telescope cylinder.
Using a suitable lifting device attached to the sling
carefully pull the telescope cylinder from the boom
assembly.
9. Using another lifting device, support the rod end of
the cylinder and remove the cylinder from the boom
assembly.
10. Carefully lift the cylinder clear of the boom assembly
and lower to the ground or suitably supported work
area.
Figure 5-23. Lower Lift Cylinder Removal
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