2014/11/03 Caterpillar

Off-Highway Truck/Tractor:

797F (S/N: LAJ1-UP; WSP1-UP)

Service Magazine SEPD1865, 08 Oct 2014, "A New Fastener Group Is Now Used on Certain 797F Off Highway Truck Engines". Disregard this article. Refer to the article that follows.

Description of Change: The new fastener group is better suited for the stresses of engine operation.

Adaptable To: The new 450-8788 Fastener Group replaces the existing 364-3909 Fastener Group. The new fastener group is adaptable back to first production on the serial numbers listed above.

Refer to Table 1 for the new and former part numbers.

Table 1

New Part Number	Former Part Number
450-8788	364-3909
274-7709	274-7709
148-5379	360-1190

This hardware change is effective for the serial numbers listed in Table 2.

Table 2

Effective Serial Numbers

S/N:LLM01312-UP

S/N:A4K01009-UP

S/N:ZK301061-UP

Additionally, the bolt torque has been increased from 700 N·m (516 lb ft) to 800 ± 100 N·m (590 ± 74 lb ft), which is standard torque for the bolt. The torque change is effective with the serial numbers listed in Table 3.

Table 3

Assembly Line Torque Change (700 Nm) to 800 Nm

Effective Serial Numbers

S/N:LLM01401-UP

S/N:A4K01023-UP

S/N:ZK302044-UP

Note: When reworking to the new fastener group, replace the four 274-7709 Bolts that were located in the counterbored locations of the 360-1190 Spacer Plate.

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Illustration 1	g03728584

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Illustration 2	g03728593

1. Starting at the 12 o'clock position and working clockwise, label the bolts from 1 through 16.

2. Torque damper bolts 1 through 16 in the following order to 800 ± 100 N·m (590 ± 74 lb ft), which is standard torqued. Torque sequence is 1-9-5-13-2-10-3-11-4-12-6-14-7-15-8-16.