BLOCK 7M4000 - Caterpillar

Image1.1.1
B) Acceptance/rejection criteria:
During step 6 and/or 9, if the actuation torque for counter steering is higher than 5 Nm, replace the steering valve group according to procedure below.
C) Replacement procedure:
1. Position the machine with the upper frame rotated by 45? counterclockwise in order to get access below the cab.
2. Stop the machine. Release the hydraulic system pressure. Refer to Disassembly and Assembly, "Hydraulic System Pressure - Release" and follow the safety instructions:
"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, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates."
3. Remove the cap from the hydraulic tank and install a vacuum pump onto the hydraulic tank. Attach an air supply hose and apply 276 to 414 kPa (40 to 60 psi) of air.
4. Remove the bottom cover below the cab in order to get access to the steering valve group.
5. Cut the 7K-1181 Cable Strap that is tied to the steering valve group and the 9X-6772 Cable Strap in order to be able to disconnect the electrical connector from the steering column to the machine harness.
Image1.3.1
6. Mark and disconnect the 5 hoses from the steering valve group and plug them with caps.
Image1.4.1
7. Remove the 6 125-6083 Screws and the 2 7Y-7388 screws. Refer to Image 1.5.1.
8. Remove the rear 243-4052 Cover from the steering column. Refer to Image 1.5.1.
Image1.5.1
9. Untighten the 2 282-0591 Band Clamps on the steering column in order to loosen the front 243-4051 Cover. Remove the bottom 243-4053 Cover from the steering column.
10. Remove the 4 8T-4136 Bolts and disassemble the steering column.
Image1.6.1
11. Remove the 4 8T-4137 Bolts and disassemble the steering valve group from the machine.
Image1.7.1
12. Remove the 4 148-8340 Connectors Assemblies and the 148-8326 Connector Assemblies from the disassembled steering valve group.
13. Replace the following seals as required:
- From the steering valve group to the 148-8340 Connector Assembly, use 4 3K-0360 O-Ring Seals
- From one 148-8340 Connector Assembly to the hose, use 4 6V-8398 O-Ring Seals
- From the steering valve group to the 148-8326 Connector Assembly, use 1 3J-7354 O-Ring Seal.
- From one 148-8326 Connector Assembly to the hose, use 1 6V-8397 O-Ring Seal.
14. Reinstall the 4 148-8340 Connector Assemblies on the new steering valve group and tighten to 82 +9/-0 Nm.
15. Reinstall the 148-8326 Connector Assembly on the new steering valve group and tighten to 22 +3/-0 Nm.
16. Reinstall the new steering valve group on the machine. Properly route the steering column harness below the cab. Tighten the 4 8T-4137 Bolts to 55 +/-10 Nm.
17. Reconnect the 4 hoses (port R, L, T, P) on the steering valve group and tighten to 65 +7/-0 Nm.
18. Reconnect hose (port LS) on the steering valve group and tighten to