JLG G12-55A AccuPlace Service Manual - Manual (Page 70)

Transmission
6.4 G10-55A & G12-55A AccuPlace
6.5.1 Transmission Removal
1. Park the machine on a firm, level surface, level the
machine, fully retract the boom, lower the boom,
place the transmission control lever in (N)
NEUTRAL, engage the park brake and shut the
engine OFF.
2. Place a Do Not Operate Tag on both the ignition key
switch and steering wheel, stating that the machine
should not be operated.
3. Open the engine cover. Allow the system fluids to cool.
4. Remove engine cover to allow easier access to the
transmission.
5. Drain the hydraulic oil reservoir. Refer to Section
8.6.1, “Hydraulic Oil Reservoir Draining.”
6. Disconnect the (+) positive and (-) negative battery
cables and remove the battery.
7. Thoroughly clean the transmission and surrounding
area, including all hoses and fittings, before
proceeding.
8. Place a suitable receptacle under the transmission
drain plug (1). Remove the transmission drain plug,
and allow the transmission oil to drain into the
receptacle. Repeat drain procedure with the drop
box (2).
9. Transfer the used transmission oil into a suitable,
covered container, and label the container as “Used
Oil.” Dispose of used oil at an approved recycling
facility. Clean and reinstall the transmission drain
plug.
10. Remove the transmission-to-axle drive shafts. Refer
to Section 5.4.3, “Drive Shaft Removal.”
11. Remove air cleaner unit and intake tubes.
12. Remove the hydraulic pump. Refer to Section 8.7.3,
“Pump Replacement.”
13. Label and disconnect the transmission temperature
switch connector and shift solenoid wiring harness
connectors.
14. Label, disconnect and cap the transmission oil
cooler inlet and outlet hoses at the transmission.
15. Remove the access plug from the bottom of the
engine bell housing. This will allow access to remove
the four bolts holding the torque convertor
diaphragm to the engine flywheel.
16. Turn the engine over slowly by hand and align each
of the four torque convertor diaphragm bolts to be
accessed. Remove them one at a time.
17. Wipe up any spilled hydraulic and transmission oil.
18. Connect a lifting strap or chain to the lifting eye at
the top of the transmission, and to a suitable hoist or
overhead crane. Operate the hoist or crane to
remove slack from the chain, but DO NOT raise the
transmission at this time.
19. Place blocks under rear of engine for support
BEFORE transmission mounts are removed.
20. Place blocks under the transmission to help support
it during removal.
21. Remove both rear transmission mount bolts and
lockwashers securing the transmission mount to the
frame.
22. Remove the twelve bolts and washers holding the
transmission to the engine.
23. Remove the capscrews and lockwashers securing
each rear transmission mount to the transmission.
24. Carefully remove the transmission from the machine.
Avoid causing damage to the transmission or
surrounding parts.
25. Lift the transmission clear of the machine, and lower
it onto suitable supports or secure it to a stand built
especially for transmission or engine service. Secure
the transmission so that it will not move or fall.
WARNING
Risk of severe personal injury. NEVER lift a
transmission alone; enlist the help of at least one
assistant or use a suitable hoist or overhead crane and
sling.
MY0980
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