JLG G12-55A Service Manual - Manual (Page 119)

7-15 G10-55A, G12-55A
Engine
7.7.2 Engine Installation
1. Secure engine with a lifting strap or chain from the
appropriate lifting points (1). Use a suitable hoist or
overhead crane.
Note: Apply Loctite ® 242™ to engine mount bracket
capscrew threads before installation.
2. Install two guide studs in bell housing holes.
3. Lift engine and slowly push and lower into engine
bay. Have an assistant ensure that engine clears
frame, hose and harness components during engine
installation. Position engine brackets over the front
frame mounts.
4. Push engine towards the transmission aligning the
guide studs and the torque convertor shaft with the
corresponding holes.
5. Push the engine against the transmission and install
eight of the ten bolts and washers. Remove both
guide studs and replace with the remaining two bolts
and washers. Torque bolts to 53-58 lb-ft (72-79 Nm).
6. Remove support from under transmission and lower
engine remainder of way onto frame. Align motor
mount holes and install bolts. Apply Loctite
® 242™
to motor mount bolts and torque to 125-140 lb-ft
(169-190 Nm).
7. Turn engine over slowly by hand and align each of
four torque convertor diaphragm bolts through
access plug in bell housing. Install them one at a
time. DO NOT fully tighten until all of capscrews
and locknuts are in place. Torque to 26-39 lb-ft
(35-59 Nm). Replace access plug.
8. Install the exhaust pipe. Refer to Section 7.5.4,
“Exhaust System Installation—LS.”
9. Secure air cleaner tube to turbo charger.
10. Connect fuel inlet line to fuel filter head.
11. Connect fuel return line to fuel filter head.
12. Install Power Distribution bracket.
13. Connect all previously labeled electrical wire
connections on Power Distribution bracket.
14. Connect all previously labeled electrical wire
connections on engine.
15. Install both heater hoses to engine and tighten
clamps (if equipped).
16. Install complete radiator assembly. Refer to Section
7.2.3, “Radiator/Oil Cooler and Replacement.”
17. Install the engine cover and adjust.
18. Install and properly connect batteries.
19. Check that all hydraulic system, electrical system,
cooling system, fuel system and exhaust system
connections are correct and connected tightly.
20. From within cab, lightly depress throttle pedal to full-
throttle position. As needed, adjust limit-stop screw
until it touches pedal bracket.
Note: Have an assistant stand by with a Class B fire
extinguisher.
21. Start the engine and run to normal operating
temperature then shut off engine. While engine is
cooling, check for leaks.
22. Allow engine to cool. Check radiator coolant level
and add coolant if required. Replace pressure cap.
23. Check for leaks from engine, main hydraulic pump
and lines, transmission, hydraulic reservoir and fuel
tank. Check the levels of all fluids and lubricants. Fill
as required.
Note: During the full throttle check:
• DO NOT operate any hydraulic function.
• DO NOT steer or apply any pressure to the
steering wheel.
• Keep the transmission in (N) NEUTRAL.
24. Obtain and connect an appropriate engine analyzer
or tachometer. Check engine rpm at full throttle.
25. Purge hydraulic system of air by operating all boom
functions through their entire range of motion several
times. Check hydraulic oil level.
26. Check for proper operation of all components.
27. Turn the engine OFF.
28. Install oil pan cover underneath engine compartment.
29. Close and secure the engine cover.
30. Remove Do Not Operate Tags from both ignition key
switch and steering wheel.