Product Support Program For Installing A New Camshaft And Lifters In Certain D11N Tractors; 776B Tractors; And 777B, 785, And 789 Trucks Caterpillar

Product Support Program For Installing A New Camshaft And Lifters In Certain D11N Tractors; 776B Tractors; And 777B, 785, And 789 Trucks

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 "PS0470" as Part Number, "7755" as Group Number, and "96" as Description Code.

NOTE: Although this Program is to be administered as described above, new lifters and camshafts can be installed before failure (when no camshaft spalling is found) either at overhaul or at any other convenient time to update.

NOTE: This Revised Service Letter replaces the July 31, 1990 (Revised November 1992) Service Letter. A change was made to the Termination Date and Mail Code AU-100 was removed.

Termination Date

January 31, 1994

Problem

The lobes on the camshafts may spall and cause damage to the valve lifters in the engines of certain D11N Tractors; 776B Tractors; and 777B, 785, and 789 Trucks.

Affected Product
Model & Identification Number

NOTE: Group 1 Affected Product require new lifters and a new camshafts. Group 2 Affected Product only require a new camshaft.

Group 1

D11N (74Z1-795)

776B (6JC1-83)

777B (4YC1-1344; 3NF1-42)

785 (8GB1-415)

789 (9ZC1-399, 9ZC401, 9ZC402, 9ZC404)

Group 2

D11N (74Z796-906, 74Z908)

777B (4YC1345-1536, 4YC1538, 4YC1540, 4YC1541)

785 (8GB416-500, 8GB502, 8GB504)

789 (9ZC400, 9ZC403, 9ZC405-541, 9ZC543)

Parts Needed

D11N Tractors

1 - OR3490 Camshaft (RH)

1 - OR3489 Camshaft (LH)

^*24 - 4P1827 Lifter Assembly

4 - 3P0647 Seal - Governor Drive

2 - 7N4320 Gasket - Rear

2 - 8N9885 Gasket - Front

1 - 8T2230 Seal - Accessory Drive Yoke

1 - 8N8089 Gasket - Trans Oil Cooler Lines

1 - 7N3368 Gasket - Trans Oil Cooler Lines

1 - 3K0360 Seal - Trans Oil Cooler Lines

3 - 3D2824 Seal - Trans Oil Cooler Lines

1 - 7M8485 Seal - High Speed Oil Change (use as required)

4 - 2M5173 Seal - Air Lines

1 - 7W2478 Gasket - Dust Ejector Tube

2 - 7J9108 Seal - Fuel Line

4 - 4J0522 Seal - Hydraulic Lines/Oil Lines

1 - 1P3704 Seal - Hydraulic Fan Lines

1 - 6V8260 Seal - Accessory Drive Yoke

3 - 8M5661 Seal - Convertor Oil Lines

2 - 8M8157 Seal - Convertor Oil Lines

2 - 8M4443 Seal - Convertor Oil Lines

1 - 8M5254 Seal - Convertor Oil Lines

2 - 8M4986 Seal - Convertor Oil Lines

1 - 8M4390 Seal - Convertor Oil Lines

2 - 3F5792 Seal - Auxiliary Rear Drive

1 - 8T7212 Seal - Hydraulic Oil Lines

1 - 2H6338 Seal - Hydraulic Oil Lines

1 - 1P3705 Seal - Hydraulic Oil Lines

10 - 7N2048 Bearing - Camshaft

These are the parts required to remove the engine from the tractor, make the repair, and install the engine back in the tractor.

776B Tractors And 777B Trucks

1 - OR3490 Camshaft (RH)

1 - OR3489 Camshaft (LH)

^*24 - 4P1827 Lifter Assembly

2 - 8N9885 Gasket - Front

2 - 7N4320 Gasket - Rear

4 - 3P0647 Seal - Governor Drive

10 - 7N2048 Bearing - Camshaft

Parts are for an in-chassis repair.

785 Trucks

8GB1-229 Equipped with Engines 96Z1-333

^*1 - 8N7659 Camshaft - Front (LH)

^*1 - 8N7660 Camshaft - Rear (RH)

^*1 - 8N7657 Camshaft - Front (RH)

^*1 - 8N7656 Camshaft - Rear (LH)

36 - 4P1827 Lifter Assembly

2 - 8N9885 Gasket - Front

2 - 7N4320 Gasket - Rear

4 - 3P0647 Seal - Governor Drive

^*14 - 7N2048 Bearing - Camshaft

8GB230-417 Equipped with Engines 96Z334-Up

1 - OR3493 Camshaft - Front (LH)

1 - OR3492 Camshaft - Rear (RH)

1 - OR3491 Camshaft - Front (RH)

1 - OR3494 Camshaft - Rear (LH)

^*36 - 4P1827 Lifter Assembly

2 - 8N9885 Gasket - Front

2 - 7N4320 Gasket - Rear

4 - 3P0647 Seal - Governor Drive

14 - 7N2048 Bearing - Camshaft

Parts are for an in-chassis repair.

789 Trucks

1 - OR3495 Camshaft - Rear (LH)

1 - OR3497 Camshaft - Front (LH)

1 - OR3496 Camshaft - Front (RH)

1 - OR3498 Camshaft - Rear (RH)

^*48 - 4P1827 Lifter Assembly

2 - 8N9885 Gasket - Front

2 - 7N4320 Gasket - Rear

4 - 3P0647 Seal - Governor Drive

18 - 7N2048 Bearing - Camshaft

Parts are for an in-chassis repair.

^*Use as needed for repairs to Group 2 Affected Product and for repeat repairs to Group 1 Affected Product.

Action Required

Parts Stock

Remove all 7W8121, 9Y9587, and 7E5246 Lifters from parts stock.

Affected Product

Refer to the June 4, 1990 Service Magazine article titled " New Lifter Assembly Reduces Pitting And Spalling Of Camshaft Lobes. " Replace the damaged camshaft and all valve lifters after a failure occurs.

Service Claim Allowances

Parts Stock

Submit one claim for all 7W8121, 9Y9587, and 7E5246 Lifters from parts stock.

Affected Product

NOTE: This is a 30 to 70-hour job.

When new lifters and camshafts are installed at overhaul or before failure at any other convenient time to update, participation will be limited to the new lifters and camshafts only per the participation schedule shown above. No labor will be allowed at overhaul, during an out-of-frame engine repair, or when the lifters are installed before failure.

NOTE: In all cases, if there has been a previous repair, part age will apply. Retain a copy of the previous repair invoice in the dealer's records for audit purposes, and specify repair date and machine hours in the "Additional Comments" section of the warranty claim.