Rework Procedure for the Tube Assembly of the Yoke{7050, 7051} Caterpillar

Paving Compactor:

CP-563D (S/N: 9ZW1-300)

Introduction

This Special Instruction, REHS1638 provides information in order to rework the tube assembly of the yoke.

Rework Procedure

Show/hide table



Illustration 1	g01001040

1. Park the machine on a level surface. Place chocks forward of drive tires and to the rear of drive tires. Lower the blade, if the tractor unit has a blade. Support the front of the tractor unit under the front bulkhead. Support the rear of the tractor unit under the bumper.

Show/hide table



Illustration 2	g01000257

Show/hide table



Illustration 3	g01002099

2. Place supports under each side plate of the drum.

Show/hide table



Illustration 4	g01002118

3. Clean the hydraulic fittings of the vibratory drum motor.

Show/hide table



Illustration 5	g01002127

4. Clean the drive motor ports.

5. Disconnect the hoses and cap the hoses in order to prevent contamination. Cap the fittings in order to prevent contamination.

Show/hide table



Illustration 6	g01002142

6. Remove the hose clamp from side plate (1).

Show/hide table



Illustration 7	g01000303

7. Remove the clamps that secure the hoses and wiring harnesses to the tube.

8. The hoses should be pulled back out of the way.

Show/hide table



Illustration 8	g01000300

9. Remove the steer cylinder to hitch pins. Remove the upper blocks and remove the lower blocks that attach the pin to the rear frame.

10. Use a crane to separate the yoke assembly from the tractor unit.

Show/hide table



Illustration 9	g01000335

11. Weld a bar across the width of the yoke. The bar should attach to the top of each side plate. The bar should be positioned in front of the tube assembly in order to allow the removal of the tube assembly.

    Note: If the yoke is not equipped with the rear scraper, weld an additional bar across the bottom of the yoke side plates.

12. There are two methods of locating the new yoke tube that depend on available shop equipment.
    Show/hide table
    
    

    Illustration 10	g01000417

    1. Overhead lift is the first method for locating the new yoke tube. In this case locate the weld fixture plates against the bottom side of the existing yoke tube 40 mm (1.6 inch) from the edge of the tube.

    2. The second method is a hydraulic jack. In this case, locate the weld fixtures plates against the top side of the yoke tube. The new yoke tube will be raised with a hydraulic jack. The yoke tube will be held with a hydraulic jack.

Show/hide table



Illustration 11	g01000429

13. By using a cutting torch, cut two welds that secure the yoke tube to the side plates. The first weld will be on the drum side of the yoke tube. The next cut will be to the top weld.

Show/hide table



Illustration 12	g01000411

Show/hide table



Illustration 13	g01001030

14. After the welds are cut, locate (2) weld fixture plates 6.35 mm (0.25 inch) against the bottom or top side of the existing yoke and one fixture plate 6.35 mm (0.25 inch) against the front side of the tube. These plates are located 40 mm (1.6 inch) from the edge of the tube.

Show/hide table



Illustration 14	g01000415

Show/hide table



Illustration 15	g01000420

15. Support the yoke tube. Cut the tube away from the plate. Leaving about 102 mm (4 inch) of tube on the yoke side of the plate

Show/hide table



Illustration 16	g01000423

16. Completely remove the yoke tube ends. Be careful not to dislodge the weld fixture plates. Remove the paint and existing slag from the side plate.

Show/hide table



Illustration 17	g01000435

17. Remove the hitch group from the old yoke tube. Install the hitch group in the new yoke tube. See Disassembly and Assembly, KENR7037, "Yoke and Steer Pivot".

18. Grind all paint from the beveled ends of the new yoke tube.

    Note: Remove the paint in order to help prevent porosity in the welds. Also, remove the paint in order to prevent inclusions in the welds.

Show/hide table



Illustration 18	g01000443

19. Position the new tube assembly in the temporary fixture. The new tube assembly should be level with the side plates.

    Note: It may be necessary to spread the yoke side plates in order to fit the new tube in place.

20. Tack weld the tube assembly to the side plates.

21. Remove the temporary plates that were used for the fixture. Also, remove the temporary bars from the bottom of the side plates and from the top of the side plates.

Show/hide table



Illustration 19	g01001107

22. Finish weld the tube assembly to the side plates of the yoke.

Show/hide table



Illustration 20	g01000451

23. By using the crane, attach the yoke assembly to the tractor unit. Secure the hitch to the tractor unit by using the bolt-down clamps. Tighten the attaching bolts (1) to 800 ± 100 N·m (590 ± 74 lb ft).

24. Reroute the hoses across the top of the new yoke tube and secure using the original clamps. Connect hose assembly to the vibratory drum motor and connect the hose assembly to the drive motor ports.

25. Remove the support stands.

26. Finish painting the welded areas.