JLG G6-42A Guide

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1.1 GENERAL GUIDELINES
•This repair procedure provides repair information for
a specific discrepancy. It is the responsibility of the
entity performing the repairs to determine if the
discrepancy can be corrected by this procedure. This
repair is only for the replacement of the rear axle
weldment.
•After inspection, if only weld cracks and NO plate
deflection is found, refer to instructions 31212011.
•After inspection, if weld cracks AND plate deflection
is found, complete the Rear Axle Block Weldment
Replacement Instructions.
1.2 WELD REPAIR GUIDELINES
•All welding must be in accordance with ANSI/AWS
D1.1 Standard.
•Disconnect the battery of the machine being repaired
prior to welding.
•Ground only to the component being welded. Do not
ground to any adjacent component or allow pins,
wear pads, wire ropes, bearings, gears, seals,
valves, electrical wiring, or hoses to be between the
grounding position and the area to be welded.
1.3 TOOLS & EQUIPMENT REQUIRED
1. Stands and lifting equipment capable of lifting/
supporting the affected components
2. Hand-held power grinder
3. Air carbon-arc equipment
4. Electric welding equipment
5. AWS 70 grade, low hydrogen rod or wire
6. Standard welder tools
7. Standard mechanic tools
8. Paint
1.4 PERSONNEL REQUIRED
1. Qualified JLG Equipment Mechanic
2. Certified Welder
1.5 PARTS LIST
1.6 REAR AXLE BLOCK WELDMENT
REPLACEMENT
1. Remove any attachment from the machine.
2. Park the machine on a firm, level surface with the
machine level, retract and level the boom. Place the
transmission control lever in the (N)
NEUTRAL position and engage the
parking brake. Shut the engine OFF.
3. Place a Do Not Operate Tag on both the
ignition key switch and the steering
wheel, stating that the machine should
not be operated.
4. Open the engine cover. Allow system
fluids to cool.
5. Properly disconnect the battery.
6. Properly support the frame to alleviate
pressure or stress at the affected repair
area.
7. Remove components as required to
facilitate repair. Refer to the machine
Service Manual for proper disassembly
procedures.
NOTICE
Reference the Service Manual for safe and proper
disassembly/assembly procedures.
NOTICE
Failure to comply with the above weld repair guidelines
may result in component damage.
P/N Qty Description
91476013 1 Rear Axle Weldment Block
G6-42A
Rear Axle Block Weldment
Replacement Instructions
For Kit 1001126991
B
7/14
31200680
An Oshkosh Corporation Company

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G6-42A Rear Axle Block Weldment Replacement Instructions For Kit 1001126991
8. Protect any hoses, wires and hydraulic cylinder rods
before preparing or welding in the axle mount area.
9. Use air carbon-arc equipment or a portable power
grinder to remove the damaged rear axle mount
weldments (4) from the frame weldment.
10. Inspect the affected areas for cracks. If any
discrepancies are evident, notify a certified welder for
further evaluation.
11. Prepare the repair area (5) for the installation of the
new rear axle weldment.
12. Locate the Axle Weldment (6) P/N 91476013 using
1.6.1 “Rear Axle Weldment Welding Locations” on
page 3. Tack weld into position.
13. Weld the rear axle weldment into place using the
recommended weld material.
14. Inspect welds using the magnetic particle or dye-
penetrant inspection methods to assure there are no
cracks or deformities. If any cracks or deformities
exist, grind to remove affected area(s) and repeat the
weld and inspection procedures.
15. Remove the weld bars (7) from the rear axle
weldment.
16. Clean, prime and paint the affected areas.
17. Install previously removed components. Refer to the
machine Service Manual for proper assembly
procedures.
18. Remove all protective coverings from any hoses,
wires and hydraulic cylinder rods.
19. Properly connect the battery.
20. Close and secure the engine cover.
21. Cycle the drive, steer and frame level functions a
minimum of five times.
22. Verify proper clearance between the frame, rear axle,
hydraulic hoses and electrical wires.
23. Install the previously removed attachment.
24. Remove the Do Not Operate Tag from the ignition
key switch and the steering wheel.
25. Return machine to service.
NOTICE
Do not damage the parent metal during this procedure.
MY5230
4
MY5250
5
NOTICE
Do not damage the rear axle weldment during this
procedure.
MY4420
6
7

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G6-42A Rear Axle Block Weldment Replacement Instructions For Kit 1001126991
1.6.1 Rear Axle Weldment Welding Locations
A. 1.0 in (25,4 mm)
5/16
WELD ALL AROUND EXCEPT AGAINST REAR PLATE
3/8
A
MY5260

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G6-42A Rear Axle Block Weldment Replacement Instructions For Kit 1001126991
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