JLG G6-42A Service Manual - Manual (Page 53)

3-15 G6-42A, G9-43A, G10-43A
Boom
30. Start engine and operate all boom functions several
times. Check for leaks, and check hydraulic fluid
level in reservoir; add fluid if required.
31. Clean up all debris, hydraulic fluid, etc., in, on, near
and around the machine.
32. Close and secure the engine cover.
33. Remove Do Not Operate Tags from both ignition key
switch and steering wheel.
3.6 EXTEND/RETRACT CHAIN
REMOVAL/INSTALLATION
3.6.1 Extend/Retract Chain Removal
The following section explains the removal of the extend/
retract chains without removing or disassembling the
boom assembly.
1. Park machine on a hard, level surface, level
machine, fully retract boom, level boom, place
transmission control lever in (N) NEUTRAL, engage
park brake and shut engine OFF.
2. Place a Do Not Operate Tag on both the ignition key
switch and the steering wheel.
3. Open engine cover. Allow system fluids to cool.
4. Properly disconnect battery.
5. Remove cover from the rear of first boom section.
6. Remove extend/retract cylinder hydraulic
tubes (4). Plug tube ends and cap the fittings to keep
dirt & debris from entering hydraulic system.
7. Remove extend/retract cylinder mounting pin (5)
from strong back.
8. Remove extend chain adjustment nut and lock nut
(6) from strong back.
9. Remove the retract chain adjustment and lock nuts
(7) from the front of the first boom section.
10. Remove the strong back mounting bolts and remove
the strong back from the boom.
11. Remove push beam mounting pins from rear of
second boom section.
12. Place chain clevis rod to one side of push beam.
13. Lift the push beam to gain access to the chain clevis
at the rear of the third boom section.
14. Reaching inside the rear of the boom at the chain
anchor bracket, remove the cotter pin and pin from
the retract chain clevis. Remove the cotter pin and
pin from the extend chain.
15. Connect wire or rope (approximately 30 ft (9,1 m) to
the end of the extend chain.
16. Lower push beam. Center chain clevis rod on push
beam to aid in removal.
17. Pull push beam/extend chain from rear of boom.
Disconnect wire or rope from extend chain.
18. Pull the retract chain from the rear of the boom.
3.6.2 Extend/Retract Chain Installation
The following section explains the installation of the
retract chains without removing the boom assemblies.
Inspect and lubricate chains thoroughly before
installation.
1. Push the retract chain through the boom from the
rear to the chain adjusting block (7) on the first boom
section. Do not tighten the adjustment and lock nut
at this time. Thread the nut on the clevis enough to
keep the chain in place.
2. Connect the extend chain to the wire or rope at the
rear of the boom.
MY0580
5
4
6
MY1540
7