Cylinder Removal And Installation; Main Boom Lift Cylinder Removal; Main Boom Lift Cylinder Installation - JLG E450A Service And Maintenance Manual

SECTION 5 - BASIC HYDRAULIC INFORMATION & SCHEMATICS

5.4 CYLINDER REMOVAL AND INSTALLATION

Main Boom Lift Cylinder Removal

NOTE: The Main Boom weighs approximately 450lbs. (204kg).
1. Place the machine on a flat and level surface. Place the
Main Boom in a horizontal position. Place Lower and
Mid Booms 5 degree above horizontal. Support the plat-
form end of main boom with suitable lifting device. Shut
down machine and prop boom.
2. Tag and disconnect hydraulic lines from the main lift cyl-
inder. Use suitable container to collect any residual
hydraulic fluid. Cap hydraulic lines and ports.
NOTE: The Main Boom Lift Cylinder weighs approximately 97 lbs.
(44kg).
3. Secure the main boom lift cylinder with suitable lifting
device.
4. Remove the hardware securing the cylinder rod attach
pin #1 to the boom. Using a suitable brass drift, drive out
the cylinder rod attach pin #1.
Figure 5-142. Main Boom Lift Cylinder Removal
5. Remove the hardware securing the barrel end attach pin
#2. Using a suitable brass drift, drive out the barrel end
attach pin #2.
6. Carefully remove the main lift cylinder from the boom
and place in a suitable work area.
5-126

Main Boom Lift Cylinder Installation

NOTE: Coat I.D. of bushings with specified lubricant prior to
installing pins.
NOTE: The Main Boom Lift Cylinder weighs approximately 97 lbs.
(44kg).
1. Using suitable lifting device, place the Main Lift Cylinder
in the position and align with mounting holes on
upright.
2. Using a suitable drift, drive the barrel end attach pin #2
through the mounting holes in the lift cylinder and
upright. Secure in place with pin retaining hardware.
3. Remove cylinder port plugs and hydraulic line caps and
correctly attach lines to cylinder ports.
4. With function speed switch at its slowest setting, extend
the cylinder rod until attach pin hole aligns with those in
boom. Using a suitable drift, drive the cylinder rod
attach pin #1 through the aligned holes. Secure the pin
in place with pin retaining hardware.
5. Remove the lifting device from the main lift cylinder.
6. Cycle cylinder completely to check for proper function-
ing. Place boom in stowed position. Check hydraulic
fluid level and adjust accordingly.
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