10 third & fourth boom section installation, Third & fourth boom section installation – JLG G12-55A Service Manual User Manual
Page 48

Boom
3-14
G10-55A, G12-55A
3.5.10
Third & Fourth Boom Section
Installation
Note: Refer to Section 2.2, “Torque Charts,” for
standard bolt torque information.
Note: Refer to Section 2.2.3, “Hydraulic Hose Torque
Chart,” for standard hose torque information.
Note: Apply Loctite
®
242 to all boom assembly bolts.
Note: Using a straight bar approximately 40 in
(1041 mm) long will aid in the installation of the wear
pads located on the inside front of each boom section.
1. Place the sling or using two slings for better stability,
around the third boom section and slowly insert the
third and fourth boom sections into the second boom
section being careful not to damage any surrounding
components.
2. Install adjusting block (17) using existing hardware
(18). Torque as required.
3. Install chain & clevis (19), spring (20), spring stop
(21), adjusting nut and lock nut (22).
4. Allow 0.50 in (1,27 mm)(A) between the end of the
clevis (23) and the face of the lock nut (24). Torque
lock nut to 100 lb-ft (135 Nm).
5. Properly connect the battery.
6. Retract the second boom section pulling both retract
chains at the same time.
7. Install the previously removed wear pad support
plates and spacers (25) with existing hardware at the
inside top front of the second boom section. Snug
mounting bolts. Shim as needed AFTER boom
section is installed to maintain a 0.070 - 0.130 in
(1,78 - 3,30 mm) gap between the boom sections.
Note: Longer bolts may be required to fully engage the
threaded inserts in the wear pads without allowing bolts
to protrude past the chamfer on the wear pads. Refer to
Section 3.11.2, “Wear Pad Installation and Lubrication.”
8. Install the previously removed wear pads, spacers
and shims on each side at the front of the second
boom section (26). Snug mounting bolts. Shim as
needed AFTER boom section is installed to maintain
a 0.070 - 0.130 in (1,78 - 3,30 mm) gap between the
boom sections.
MY3540
18
17
19
18
21
22
20
A
MY3650
24
23
MY3450
25
25
26
26
MY3450
28
29
30
30
29
28
27