JLG G6-42A Service Manual - Manual (Page 70)

Boom
3-32 G6-42A, G9-43A, G10-43A
Hoses:
• Two Hydraulic Hoses - Approximately 10 ft
(3,0 m) each, with a minimum I.D. of
0.375 in (9,5 mm) and a minimum rating of
4000 psi (275,8 bar).
G6-42A - Fittings:
• Two -10 ORFS Caps
• Two -10 ORFS Plugs
Adaptors:
• Two -10 ORFS 90° Adaptors
G9-43A or G10-43A - Fittings:
• Two -12 ORFS Caps
• Two -12 ORFS Plugs
Adaptors:
• Two -12 ORFS 90° Adaptors
Note: The adaptor size may vary depending on the
hose ends of the auxiliary hydraulic power supply.
3.13.2 Lowering Procedure
a. Retract the boom as follows:
1. If equipped with Personal Work Platform, rescue
occupants prior to performing procedure.
2. Properly support the boom before attempting to
proceed with the emergency boom lowering
procedure.
3. Place a Do Not Operate Tag on both the ignition key
switch and steering wheel.
4. Properly support the boom as required.
5. Place a suitable receptacle under the tube/hose
connections.
6. Remove the plastic cover from the main control
valve.
7. If access is required, loosen and remove any clamps
securing the lift/lower cylinder (1 & 2) and extend/
retract cylinder tubes (3 & 4) to the frame.
8. Disconnect the extend/retract cylinder tubes from
the extend/retract cylinder hoses (3 & 4). Install caps
or plugs in tubes to prevent fluid loss and to keep dirt
and debris from entering the hydraulic system.
WARNING
Loss of hydraulic oil is limited to the amount trapped
within each tube/hose. Slowly loosen each hydraulic
tube/hose fitting to release any possible hydraulic oil
pressure that may be trapped between the main
control valve and the counterbalance valve of the
extend/retract cylinder or the lift/lower cylinder. MY8630
MY8620
G6-42A
1
4
G9-43A
G10-43A
3 2
4
2
3
1