- Off-Highway Truck/Tractor:
- 793F (S/N: SND1-UP; SSP1-UP; RBT1-UP)
Introduction
ReferenceOperation and Maintenance Manual, SEBU8406, "793F and 793F XQ Off-Highway Truck", "Prepare the Machine for Maintenance"
ReferenceOperation and Maintenance Manual, SEBU8406, "793F and 793F XQ Off-Highway Truck", "Welding on Machines and Engines with Electronic Controls"
ReferenceOperation and Maintenance Manual, SEBU8571, "793F CMD (Command for Hauling) Off-Highway Truck", "Prepare the Machine for Maintenance"
ReferenceOperation and Maintenance Manual, SEBU8571, "793F CMD (Command for Hauling) Off-Highway Truck", "Welding on Machines and Engines with Electronic Controls"
ReferenceSpecial Instruction, REHS1841, "General Welding Procedures"
This special instruction provides the required parts and the correct procedure to improve the routing and the clipping of a tube assembly and a hose assembly in the service brake control group. The new parts and routing will help reduce leaks and cracking found near the brake oil filter.
This special instruction is applicable to machines S/N:SSP1-1060, ; S/N:RBT1-171, and ; S/N:SND1-131.
Important Safety Information
Do not perform any procedure in this special instruction until you have read this special instruction and you understand this information. Use only proper tools and observe all precautions that pertain to the use of those tools. Failure to follow these procedures can result in personal injury. The following procedures should also be observed.
Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs.
A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools in order to perform these functions properly.
Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard.
Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. If the tools, the procedure, and the work method are not recommended by Caterpillar, ensure that the tools, the procedure, and the work method are safe for you and for others.
Ensure that the product will not be damaged or the product will be made unsafe by the operation, lubrication, maintenance, or the repair procedures.
Required Parts
| Required Parts | |||
| Item | Qty | Part Number | Description |
| 1 | 1 | 9R-2640 | Boss |
| 2 | 1 | 191-2962 | O-Ring Seal |
| 3 | 1 | 462-1649 | Hose As |
| 4 | 4 | 5p-8112 | Grommets |
| 5 | 4 | 5P-7466 | Clips |
| 6 | 4 | 5P-7467 | Clips |
| 7 | 2 | 8T-4139 | Bolts |
| 8 | 2 | 8T-4223 | Hard Washers |
| 9 | 3 | 5K-5338 | Clips |
| 10 | 2 | 8T-4195 | Bolts |
| 11 | 6 | 8T-4121 | Hard Washers |
| 12 | 3 | 344-5675 | Nuts |
| 13 | 2 | 228-7093 | O-Ring Seals |
| 14 | 1 | 462-1650 | Tube As |
| 15 | 1 | 8T-4183 | Bolt |
| 16 | 2 | 5P-1076 | Hard Washers |
| 17 | 1 | 329-3356 | Nut |
| 18 | 1 | 463-1923 | Plate |
| 19 | 1 | 6D-4244 | Clip |
| 20 | 1 | 8T-4136 | Bolt |
Prepare the machine for Maintenance
Prepare the machine for maintenance. For the correct procedures, refer to the above listed information for your machine.
Rework Procedure
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| Illustration 1 | g03726179 |
Area (AA) is the location of the updates on the machines.
- Remove four bolts (A), four washers (B), and two half flanges (C) from the machine. Save the parts.
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| Illustration 2 | g03726183 |
| NOTICE |
|---|
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products. Dispose of all fluids according to local regulations and mandates. |
- Remove hose assembly (D), and O-Ring Seal (E) from the machine. Discard the parts.
- Remove bolt (F), washer (G), clips (H), and grommet (J) from the machine. Discard all of the parts.
- Remove bolt (N), washer (P), spacer (R), clips (S), and grommet (T) from the machine. Discard all of the parts.
- Remove tube assembly (L), and two O-Ring Seals (M) from the machine. Cover the end of hose assembly (U) in order to prevent contamination of the system Discard all of the parts.
- Remove boss (K) from the machine. Discard the part.
- Use the information in Illustration 3 to position boss (1). Mark the location for the boss.
Note: The crosshair is located where the axis for the boss meets the surface of the center tube. The center of the boss that is shown is at the bottom of the boss.
 | |
| Illustration 3 | g03726186 |
Position of boss (1) (A) 89.5 mm (3.52 inch) (B) 602 mm (23.7 inch) | |
- Prepare the area for welding. For the proper procedure, refer to the information in "General Welding Procedures". Also read the above listed information for your machines about welding on machines and engines with electronic controls.
- Use the information in Illustration 3 to position boss (1). Use the information in Illustration 3 to weld the boss to the machine.
Note: The crosshair is located where the axis for the boss meets the surface of the center tube. The center of the boss that is shown is at the bottom of the boss.
 |
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 kill. Read and understand the manufacturer's instruction and your employer's safety practices. Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing zone and the general area. Wear correct eye, ear and body protection. Do not touch live electric parts. Refer to the American National Standard Z49.1, "Safety in Welding and Cutting" published by the American Welding Society, 2501 N.W. 7th Street, Miami, Florida 33125: OSHA Safety and Health Standards, 29 CFR 1910, available from U.S. Dept. of Labor, Washington D.C. 20210. |
 |
| NOTICE |
|---|
Do not ground the welder to electrical components such as the ECM or sensors. Improper grounding can cause damage to the drive train bearings, hydraulic components, electrical components, and other components. Clamp the ground cable from the welder to the component that will be welded. Place the clamp as close as possible to the weld. This will help reduce the possibility of damage. |
- Four bolts (A), four washers (B), and two half flanges (C) were removed in Step 1. Retrieve the parts.
 | |
| Illustration 4 | g03726407 |
- Assemble one O-Ring Seal (2) onto hose assembly (3). Use the retrieved parts from the previous step to assemble the hose assembly to the machine.
- Assemble one O-Ring Seal (13) into each end of tube assembly (14) .
- Assemble the short end of tube assembly (14) to hose assembly (3). Uncover the end of hose assembly (U). Assemble the other end of the tube assembly to the hose assembly (U) .
- Assemble one grommet (4) to tube assembly (14) near the end as shown. Assemble one clip (5), and one clip (6) around the grommet. Use one bolt (7), and one hard washer (8) to secure the hose assembly to boss (1) .
- Assemble one grommet (4) to tube assembly (14) near the two harness assemblies as shown. Assemble one clip (5), and one clip (6) around the grommet. Assemble one clip (9) around the two harness assemblies near the clips. Align the holes in the clips. Use one bolt (10), two washers (11), and one nut (12) to secure the clips.
- Go to the bend in the other end of tube assembly (14). Assemble one grommet (4) to tube assembly (14) near the two harness assemblies as shown. Assemble one clip (5), and one clip (6) around the grommet. Assemble one clip (9) around the two harness assemblies near the clips. Align the holes in the clips. Use one bolt (10), two washers (11), and one nut (12) to secure the clips.
- Go to the bracket that is below the harness assemblies. Use one bolt (7), and one hard washer (16) to assemble the short end of plate (18) to the bracket.
- Assemble one grommet (4) to tube assembly (14) near the end of plate (18) as shown. Assemble one clip (5), and one clip (6) around the grommet. Align the hole in the clips with the hole in the plate. Assemble one hard washer (16) to one bolt (15). Assemble the bolt to the plate and clips. Use one hard washer (8), and one nut (17) to secure the parts.
- Go to the area near hose assembly (3) where the two harnesses pass near the hose assembly outside the mounting plate. Assemble clip (9) around the two harness assemblies. Assemble one clip (19) around the hose assembly outside the mounting plate. Align the holes in the two clips. Use one bolt (20), two hard washers (11), and one nut (12) to secure the clips.