SUBJECT: LOOSENING THE BRACKET FIXATION BOLTS WILL CAUSE SEVERE DAMAGE TO THE ROTATOR AND THE SILENT BLOCKS ON THE G310B, G315B, VRG20/2, AND VRG25/2 GRAPPLES

PROBLEM:

SOLUTION:

1. Remove the demolition and sorting grapple from the host machine. Refer to the Operation and Maintenance manual, "Removal of the Work Tool".
2. Clean the grapple before repairing.
3. Place the grapple on a flat surface, and secure it against moving.
4. Verify that bracket group 231-9194 has not been installed previously.
5. Put identification marks on all hoses, couplings and other hydraulic elements for installation purposes. Plug all hoses in order to help prevent fluid loss and contamination of the hydraulic system.



Illustration 1 Mounting Bracket

6. Remove mounting bracket (M). Refer to the Service Manual, "Mounting Bracket Removal Procedure".



Illustration 2 Identification of bracket components

7. Remove the two old brackets that are assembled on both sides of the rotator. This will gain access to the area to be welded. The rotator along with the two hydraulic blocks can remain assembled to the upper housing.

1. Grind away the paint at both areas to be welded.
2. Connect the negative ground to the upper housing and not the lower shell.

Note: No welding current is allowed to flow through the bearing or the rotator.

3. Protect the rotator by placing a cover over the rotator.



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 3

4. Place a mark 30 mm (1.18 inches) from the inside plate and a second mark 260 mm (10.24 inches).
Show/hide table

Welding Specifications
Weld Process	ISO 4063-135
Weld Quality	ISO 5817-C
Weld Position	ISO 6947-PA/PB
Weld Material	DIN 8559 SG-2

Table 5. Welding Specifications



Illustration 4

5. Place a 6 mm (0.23 inches) fillet over square groove weld with a 1.5mm (0.06 inch) penetration. Begin your weld at the 30 mm (1.18 inch) mark. See illustration 4.

Note: Make sure you conform to the welding specifications in table 5 when you make your welds.

6. Move the weld along the plate; stop the weld when you reach the bore in the bottom plate. The location of the bore is marked by "Area A" in Illustration 4.

Note: Do not weld near the bore.

Continue your weld on the other side of the bore. Move the weld along the plate until you reach the 260 mm (10.24 inches) mark.

7. Repeat steps "11" through "15" on the other side of the housing.
8. After welding is completed, clean and paint the welds.



Illustration 5

NOTE: Follow the procedure below in order to properly install the new bracket.

9. Position two 231-9198 Plates (D) on the inside of the upper housing (G). Refer to Illustration 6.
10. Install nut (E) onto rod assembly (C).
11. Install rod assembly (C) to bracket (B) as far as is possible.



Illustration 6



Illustration 7

12. Install bushing (A) into bracket (B).
13. Position the bracket assembly (B) between the mounting plates of the rotator (F).
14. Install lockwasher (I) to bolt (H).
15. Apply thread lock compound 9S-3263 (Locktite 243) onto bolt thread (H).
16. Install bolt (H) into the mounting plate of the rotator (F).
17. Tighten the bolt (H) to a torque of 200 Nm (148 lb ft).
18. Screw rod assembly (C) out of bracket (B) until the end of the rod enters the bore of plate (D).



Illustration 8 Hydraulic Blocks Not Equally Spaced



Illustration 9 Hydraulic Blocks Equally Spaced

19. Adjust rod assembly (C) to align the hydraulic blocks (X) with the bores in the upper housing assembly (G).



Illustration 10



Illustration 11

20. Align the bracket (B) with the bottom plate of upper housing assembly (G). Make sure bracket (B) is parallel with the hydraulic blocks (X).
21. Apply 9S-3263 thread lock compound (Locktite 243) onto the threads of rod (C).
22. Tighten the nuts on both ends of the rod assemblies to a torque of 50 Nm (37 lb ft).
23. Clean all parts.
24. Paint all parts that need to be painted.



Illustration 12

25. Install mounting bracket (M). Refer to the Service Manual, "Mounting Bracket Installation Procedure".
26. Reinstall the grapple to the machine. Refer to the Operation and Maintenance Manual, "Installation of the Work Tool".