Product Support Program For Reworking The Piston Pin Bearing On Certain 508 And FB508 Skidders, 910, 910E, G910, 916, 926, 926E, G926, 931, 931B, 931C, 931C Series II, 935B, 935C, 943, And 953 Loaders, D3, D3B, D3C, D3C Series II, D4B, D4C, D4C Serie Caterpillar

Product Support Program For Reworking The Piston Pin Bearing On Certain 508 And FB508 Skidders, 910, 910E, G910, 916, 926, 926E, G926, 931, 931B, 931C, 931C Series II, 935B, 935C, 943, And 953 Loaders, D3, D3B, D3C, D3C Series II, D4B, D4C, D4C Serie

Usage:

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Caterpillar: Confidential Yellow

NOTE: The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.

NOTE: This Program can only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS0657" as the Part Number and "7755" as the Group Number. Use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.

NOTE: Although this Program is to be implemented as described above on the Affected Product, parts should be removed from Parts Stock as soon as possible.

NOTE: This Revised Service Letter replaces the May 2, 1993 Service Letter, revised July 1993. Changes have been made to the Action Required.

Termination Date

May 31, 1994

Problem

The piston pin bearing may fail on certain 508 and FB508 Skidders, 910, 910E, G910, 916, 926, 926E, G926, 931, 931B, 931C, 931C Series II, 935B, 935C, 943, and 953 Loaders, D3, D3B, D3C, D3C Series II, D4B, D4C, D4C Series II, D4H, and D4H Series II Tractors, E180 and EL180 Excavators, and IT12, IT18B, IT28, and IT28B Integrated Toolcarriers.

Affected Product
Model & Identification Number

508 ( 2HD189-316, 9NC122-998)

FB508 (4JG25-33)

910 (29D82-84, 40Y8340-10342, 41Y2878-3213)

910E (1SF166)

G910 (3SD390, 8GD313-314)

916 (2XB1340-1908, 3SC5-6, 5KC1128-1789, 8GC173-196, 9WB1401-9426)

926 (1CB73-201, 4TC24, 8NB1363-2371)

926E (4NB2110-3492, 94Z2117-3627)

G926 (1SD73)

931 (25Y1955-1976, 30Y487-494)

931B (26Y523-524, 29Y2250-2273)

931C (2AK20-36, 2BJ38-381, 5LG32-34, 6RF30-121, 7HF34-120, 8AF22-26)

931C Series II (6AJ26-56, 9AG18-27)

935B (3DF127-277)

935C (5DJ26-65, 8CF72-551)

943 (19Z746-1899)

953 (1XK1-24, 20Z1474-4329, 2RB194-203, 44Z625-741, 78Y1121-1194)

D3 (27Y4841-5170)

D3B (23Y2394-2582, 24Y2314-2455, 28Y1951-2037, 2PC226-246, 3YC321-324, 5MC292-316)

D3C (1PJ138-1436, 3RF147-565, 5CJ30-286, 5KG201-1647, 6PF145-369, 7JF131-295, 8BF156-255)

D3C Series II (4HJ57-251, 5ZG16-36, 7JG28-51, 8DG18-47)

D4B (1SG191-237, 2XF413-735)

D4C (1RJ175-1425, 2CJ127-606, 7KG64-251)

D4C Series II (9BG23-110, 8ZF24-46)

D4H (2AC541-4111, 3AC527-4141, 8PB1557-4750, 9DB788-4538)

E180 (1RF129-130)

EL180 (4EF172-323)

IT12 (1FF32-40, 2YC1007-1622, 4NC1040-1781)

IT18B (1DF466-1276, 2NJ319-343, 4ZD382-1063)

IT28 (2KC1159)

IT28B 1HF 610-2348, 1JK407-4335SD516-1216)

Parts Needed

1 - 0R3274 Connecting Rod Assembly ^*

1 - 9N5082 Bearing ^*

^* Use as required

Action Required

Parts Stock

Inspect all 8N3753 Connecting Rod Assemblies in Parts Stock following the procedures provided in Step 3 below for testing the piston pin bearings.

Affected Product

1. Remove connecting rods with failed piston pin bearings from the engine. If a new bearing is pressed in to repair a rod, it must pass the test described in Step 3. If it does not pass the test, replace the rod with a 0R3274 Connecting Rod Assembly.

2. Remove all remaining connecting rods from the engine.

3. Apply an 8900 N (2000 lb.) side load to the connecting rod piston pin bearing. Bearing movement in the rod is unacceptable. If a bearing moves while under the test load, replace the rod assembly with a 0R3274 Rod Assembly.

NOTE: 0R3274 Connecting Rod Assemblies are tested at the factory.

NOTE: If using a Caterpillar 5P3639 Connecting Rod Bushing Press Group with either a 5P0156 or 5P9725 Hydraulic Cylinder, and have a gage that reads hydraulic pressure only, use the following gage reading to test rod eye bushings:

5P8639 Group with 5P0156 cylinder:

5P8639 Group with 5P9725 cylinder:

(The 5P0156 Cylinder has a rod diameter of 34.72- 34.80 mm (1.367-1.370 in) and the 5P9725 Cylinder has a rod diameter of 37.64-37.77 mm (1.482- 1.487 in))

If using something other than a 5P8639 Group, it is necessary to calculate the force-to-pressure relationship.Determine the cross sectional area of the piston used in the hydraulic cylinder using the following formula: