2013/10/10 An Improved Bearing Setting Procedure for Transfer Gears is Now Used on Certain CX31-P600 Petroleum Transmissions {3159} Caterpillar

Reference Disassembly and Assembly, KENR8152, "Transfer Gears - Assemble"

Description of Change: A new bearing setting procedure is now used during assembly to improve the durability of the transfer gear bearings.

Adaptable To:

Bearing Setting Procedure for Tapered Roller Bearings

The following steps describe the new setting procedure. Top, bottom, and idler bearings will all be set using this same procedure. Disassembly and Assembly, KENR8152, "Transfer Gears - Assemble" will be updated at a later date.

Illustration 1	g03472364
(1) Bolt and washer (2) Bearing cage (3) Shim pack (4) O-ring seal (5) Bearing cup (6) Bearing cone

1. Measure the cage flange thickness in four equally spaced places and record to two metric decimal places.

2. Ensure that the bearing cups are seated against the housing and that the bearing cone is seated against the shaft shoulder.

3. With the axis of the gear or shaft in the vertical position, assemble bearing cup and cage to housing without shim pack and o-ring seal.

4. Insert bolts and washers equally spaced 90 degrees apart into bearing cage flange. Then bring bolts and washers into contact with cage flange until finger tight.

5. Advance the cage evenly to take up clearance. Alternately tighten each of the four bolts by 1/4 turn or less. Tighten each bolt an equal number of turns until a torque of 6 N·m (53 lb in) is achieved at each bolt.

6. Rotate the shaft a minimum of three complete revolutions.

7. Tighten each bolt an equal number of turns until a torque of 12 N·m (106 lb in) is achieved at each bolt.

8. Repeat Step 6 and Step 7 until the specified torque of 12 N·m (106 lb in) will no longer advance the bolts.

9. Carefully loosen each bolt one at a time and immediately return to finger tight. Repeat for each bolt individually.

10. In at least two places 180 degrees apart, measure depth from top surface of flange to face of housing through the puller holes using a depth micrometer. Calculate and record the average of the depth measurements to two metric decimal places.

11. Subtract the appropriate average flange thickness, Step 1, from the average depth, Step 10, to determine the gap.

12. Add 0.10 ± 0.05 mm (0.004 ± 0.002 inch) to calculated gap, Step 11, to determine the total shim thickness that is needed.

13. Remove the four bolts, washers, and cage. Reassemble with the correct shim pack and o-ring seal. Tighten all bolts to meet specifications and rotate the shaft a minimum of three complete revolutions in order to ensure that the bearing is properly set.