793C Off-Highway Truck/Tractor Power Train Caterpillar

Assembly Procedure

First Reduction Planetary Component

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Illustration 1	g01058604

1. Place planetary gear (1) on a suitable bench.

2. Install retaining ring (4) in planetary gear (1).

3. Use a suitable press to install bearing cups (3).

4. Apply clean oil to bearing cones (2). Assemble the bearing cones in planetary gear (1).

5. Repeat Steps 2 through 4 for the remaining planetary gears.

6. Use a suitable lifting device to position the gear assembly in the carrier. The gear assembly weighs approximately 90 kg (200 lb).
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   Illustration 2	g01058608

7. Use a suitable press to install planetary shaft (6). Rotate planetary gear (1) while the planetary shaft is being pressed into position.

   Note: The shaft should be installed at the room temperature. Do not lower the temperature of planetary shaft (6) before installation.

8. Repeat Steps 6 and 7 for the remaining planetary gears.

9. Reposition carrier (5).
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   Illustration 3	g01058599

10. Use Tooling (B) to measure the gap between the counterbore in carrier (5) and planetary shaft (6).
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    Illustration 4	g01058617

11. Assemble shim (9) with a thickness that is equal to the gap +0.00 mm to −.05 mm (+0.00 inch −.002 inch).

12. Use two bolts (7) to install plate (8) and shim (9). Tighten bolts (7) to a torque of 135 ± 15 N·m (99.6 ± 11.1 lb ft).

    Note: Before installation, apply Tooling (D) to the threads of bolts (7).

13. Repeat Steps 7 and 12 for the remaining planetary gears.

14. Rotate each planetary gear (1) by hand. Be certain that the movement of each planetary gear (1) is uniform.

Second Reduction Planetary Component

Note: Steps 1 through 4 are for the installation of straight roller bearings.

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Illustration 5	g01053034
Machined tang (F) of gear that fits between the straight roller bearing assemblies.

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Illustration 6	g01053035
Bearing assembly (10) with retaining straps (C).

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Illustration 7	g01053037

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Illustration 8	g01053041

Note: To install the new straight roller bearing, use retaining straps (C) that hold the rollers in place.

Note: Do not use the spacer and the snap ring with the new gear and new bearing.

1. Assemble bearing (10) in gear (11). Retaining straps (C) come off bearing assembly (10) as bearing assembly (10) is installed.

2. Turn over gear (11) and repeat Step 1 for the other bearing.

3. Repeat Step 1 and Step 2 for the other planetary gears.

4. Proceed to Step 10 for final assembly.
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   Illustration 9	g00531370

5. Place planetary gears (18) on a suitable bench.

6. Install retaining ring (24) in planetary gear (18).
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   Illustration 10	g00531861

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   Illustration 11	g01058639

7. Use a suitable press to install cup (26), spacer (16), and cup (15).

8. Apply clean oil to cone (17), cone spacer (19), and cone (14). Assemble the cones and the cone spacer in planetary gear (18).

9. Repeat Steps 5 through 8 for the remaining planetary gears.

10. Place a suitable strap throught the gear and the bearing assemblies. Fasten the strap to a suitable lifting device and position the planetary gear in the carrier. The weight of the gear assembly is appoximately 125 kg (275 lb).
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    Illustration 12	g01058635

11. Use a suitable press to install planetary shaft (20). Rotate planetary gear (18) while the planetary shaft is pressed into position. Shoulder (X) of the planetary shaft must be seated against the carrier.

    Note: The planetary shaft must be installed at room temperature. Do not lower the temperature of planetary shaft (20) before installation.

12. Repeat Steps 10 and 11 for the remaining planetary gears.
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    Illustration 13	g01058645

13. Reposition the carrier.

14. Use Tooling (B) to measure the gap between counterbore (Y) and planetary shaft (20).
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    Illustration 14	g01058646

15. Assemble shim (21) with a thickness that is equal to the gap +0.00 mm to −.05 mm (+0.00 inch −.002 inch).
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    Illustration 15	g01058647

16. Use two bolts (22) to install plate (23) and shim (21). Tighten bolts (22) to a torque of 255 ± 15 N·m (188.1 ± 11.1 lb ft).

    Note: Before installation, apply Tooling (D) to the threads of bolts (22).

17. Repeat Steps 13 and 16 for the remaining planetary gears.

18. Rotate each planetary gear (18) by hand. Be certain that the movement of each planetary gear (18) is uniform.

End By:

1. Install the rear axle shafts. Refer to Disassembly and Assembly, "Axle Shaft - Install".

2. Install the carrier of the second reduction planetary component. Refer to Disassembly and Assembly, "Final Drive - Remove".