HEAD GP-MOTOR 1733439 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
When the frame of the thumb is fully retracted, the frame may come in contact with the barrel of the thumb cylinder. Deformation of the barrel may result. Interference with the frame of the thumb also causes bent linkages and damaged pins. Refer to table 1 for the affected thumbs.Solution
A 301-0922 Stop has been created. This stop may be attached to the stick of the excavator. The stop is designed to reduce any excessive play in the linkage of the thumb. The stop will also act as a positive stop for the frame of the thumb.Note: Parts must be ordered through Caterpillar Work Tools at 1-800-752-2858.
Table 1
Affected Thumbs    
Part Number     Serial Number    
264-0506     S/N:7JW3795     S/N:7JW3837     S/N:7JW3938     S/N:7JW3967    
S/N:7JW4087 S/N:7JW4328     S/N:7JW4329     S/N:7JW4497    
S/N:7JW4517 S/N:7JW4520     S/N:7JW4795     S/N:7JW4796    
S/N:7JW4797 S/N:7JW4798     S/N:7JW4799     S/N:7JW4800    
S/N:7JW4826 S/N:7JW4827        
Personal injury can result from flame cutting or welding on painted areas.The effect of gasses from burned paint is a hazard to the person doing the cutting or welding.Do not flame cut or weld on painted areas.
Personal injury or death can result from fumes, gases and ultraviolet rays from the weld arc.Welding can cause fumes, burn skin and produce ultraviolet rays.Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing area. Wear eye, ear and body protection before working.Protect yourself and others; read and understand this warning. Fumes and gases can be dangerous to your health. Ultraviolet rays from the weld arc can injure eyes and burn skin. Electric shock can cause death.Read and understand the manufacturer's instructions and your employer's safety practices. Do not touch live electrical parts.See "American National Standard Z49.1, Safety in Welding and Cutting" published by the American Welding Society.American Welding Society
2501 N.W. 7th Street
Miami, Florida 33125
See "OSHA Safety and Health Standards, 29 CFR 1910", available from U.S. Department of Labor.U.S. Department of Labor
Washington, D.C. 20210
Illustration 1 g01275116
(1) 301-0922 Stop
Illustration 2 g01312231
View of stop (1)
Illustration 3 g01312230
View of stop (1) in relation to thumb
Illustration 4 g01311624
The side plate was removed for clarification.
Open the thumb to the position that is shown in illustration 2. Use the existing stops to locate the correct position for the 301-0922 Stop .
Prepare the surface of the stick and the stop for welding.
Position the stop on the bottom plate of the stick against the power link ears of the thumb's frame. Refer to illustration 3, 4.
Weld the stop in place. Use an 8 mm fillet all the way around.
Test the operation of the thumb.
Apply paint to the stop and the stick.