TUBE AS 1975414 - Caterpillar

Introduction
ReferenceSpecial Instruction, REHS1841, "General Welding Procedures"ReferenceSpecial Instruction, SEHS0022, "Procedure to Ultrasonic Test (UT) the Rear Axle Housing of the 795F AC Off-Highway Truck"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
The rear axle housing on the 795F AC has experienced structural fractures. If not detected early, the fractures could lead to significant contingent damage and extended machine downtime. Solution
Inspect the rear axle housing for cracks. Inspections should take place daily, weekly, and during maintenance.Daily Inspection
Illustration 1 g03764080
View of the area of concern on the rear axle housingNote: The main area of concern should be the bottom of the housing.Operators should be informed to pay attention to the external area during a pre-shift machine inspectionWeekly Inspection
Illustration 2 g03764358
Note: The main area of concern should be the bottom of the housing.Dealer or site personnel should complete a visual inspection of the external area once per week. The inspection area should be clean enough so that the casting surface can be clearly seen.Inspection During Maintenance
Illustration 3 g03764317
Note: The main area of concern should be the bottom of the housing.Dealer or site personnel should inspect the internal area of the housing, between the traction motors.Note: Dye penetrant or magnetic particle method of inspection will give the best results for the internal surfaces of the casting.Reporting and Repair
Illustration 4 g03764396
View of possible cracks in the bottom of the rear axle housingWhen detected early, the housing can be weld repaired. The graphic on the left of Illustration 4 could be repaired. The graphic on the right of Illustration 4 should not be repaired. The housing should be replaced.Refer to Special Instruction, REHS1841, "General Welding Procedures" before performing any welding on the machine.
Illustration 5 g03764136
View of the casting information on the rear of the housing.The CAT logo, "NUMERALKOD", and part number are located on the left-hand side.The foundry logo and serial number are located on the right-hand side.Record the "NUMERALKOD", part number, housing serial number, and machine serial number. Submit the information to Dealer Solution Network (DSN).