JLG M450 ANSI Service Manual - Manual (Page 117)

SECTION 4 - BOOM & PLATFORM
3121127 – JLG Lift – 4-5
Installation
NOTE: Coat I.D. of bushings with specified lubricant prior to
installing pins.
1. With the booms positioned and supported, place
cylinder in position and secure in place using slings.
2. Install the cylinder barrel pin #4, 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 #3 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.
4.4 LOWER BOOM LIFT CYLINDER
Removal
1. Place machine on flat and level surface. Place the
Upper Boom in a horizontal position. Place the Mid
and Lower Booms in a 10 degree elevated position.
Support Upper Boom with a prop. Support upright
with an overhead crane.
2. Using slings, restrain the lower lift cylinder.
3. Remove the hardware securing the cylinder rod
attach pin #5 to the boom. Using an appropriate
brass drift, drive out the cylinder rod attach pin #5.
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.
Installation
NOTE: Coat I.D. of bushings with specified lubricant prior to
installing pins.
1. With the booms positioned and supported, 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.
Figure 4-4. Lower Boom Lift Cylinder Removal