BOOM & BEARING AS 2941490 - Caterpillar

Illustration 15 g03651723
Replacement Cover 9U-8692 Cover, 213-8734 Cover.
Remove the dial indicator and mount the boring bar (Tooling D) into the spindle. Perform the semi-finish, finish, and chamfer operations for the left-hand bore as shown in Illustration 14. The surface finish of the bore and the chamfer is an "H" finish. Use Tooling H to evaluate the surface finish. Refer to Table 4 for the bore dimensions.
Table 4
Machining Dimensions Summary
Diameter 1 Diameter 2 Diameter 3
Diameter 223.82 0.05 mm (8.81179 0.00197 inch) 336.55 0.05 mm (13.24997 0.00197 inch) 192.51 0.05 mm (7.57912 0.00197 inch)
Chamfer 0.8 0.2 mm (0.03150 0.00787 inch) 1.5 0.5 mm (0.05906 0.01969 inch) 1.5 0.5 mm (0.05906 0.01969 inch)
Angle 30 30 30
Finish H F F
Illustration 16 g03142132
Center (zero) the right-hand bore in the case.
Refer to Illustration 8 for bore locations and nomenclature. Move the spindle to the right-hand bore (1) and align bore (6) in the case to within 0.013 mm (0.00051 inch) TIR as shown in Illustration 16. Lock both the horizontal and vertical axes of the boring machine to ensure that the spindle location does not move.
Illustration 17 g03142138
Machine right-hand bore (1) in the cover.
Remove the dial indicator and mount the boring bar (Tooling D) into the spindle. Perform the semi-finish, and chamfer operations for right hand bore (1) in the cover as shown in Illustration 17. The surface finish for the bore and chamfer must be an "F" finish. Use (Tooling H) to evaluate the surface finish.
Illustration 18 g03142140
Center (zero) bore (5) in the case.
Move the spindle to center bore (2) of the cover. Mount the small dial indicator (Tooling K) into the spindle and center (zero) bore (5) in the case to within 0.013 mm (0.0005 inch) TIR as shown in Illustration 18. Lock both the horizontal and vertical axes to ensure that the spindle does not move.
Illustration 19 g03142142
Machine center bore (2) in the cover.
Remove the indicator and mount the boring bar (Tooling D) into the spindle. Perform the semi-finish, finish, and chamfer operations for center bore (2) as shown in Illustration 19. The surface finish of the bore and chamfer should be machined to an "F" finish. Use (Tooling H) to evaluate the surface finish.
Illustration 20 g03142145
Center (zero) one of the dowel holes in the case.
After all three bores in the cover are machined, mount a dial indicator (Tooling K) into the spindle. Center (zero) one of the existing finished dowel holes in the case to within 0.013 mm (0.00051 inch) TIR as shown in Illustration 20. Lock the horizontal and vertical axes of the machine. Remove the dial indicator.Note: The hole in the semi-finished cover is smaller than the hole in the case. Therefore, accurately determining TIR in Step 16 may be difficult. Make sure that the TIR is within 0.013 mm (0.0005 inch).Note: Place a dial indicator against the rear face of the case to check for movement during machining or installation of the dowel. If