2011/06/24 Caterpillar

Engine:

C15 (S/N: KRA1-UP; JEP1-UP; SDP1-UP; BXS1-UP; MXS1-UP; NXS1-UP; RKS1-UP)

ReferenceDisassembly and Assembly, "Pistons and Connecting Rods - Remove"

ReferenceDisassembly and Assembly, "Pistons and Connecting Rods - Disassemble"

A new piston body is available for certain C15 truck applications. The additional piston is comprised of a microalloy that incorporates a lower land support. The cylinder pack part numbers will not change. However, the pistons that are used within the packs can have a different appearance.

Illustration 1	g02611218
View of new piston

Illustration 2	g02617282
View of the current piston

The new piston that is shown in Illustration 1 is a direct replacement for the previous piston design that is shown in Illustration 2. The new pistons have the same weight and balance as the previous pistons, and meet the same emissions standards. Cylinder packs that utilize the new and previous pistons can be used together in the same engine, but the same cylinder pack part number must be used in all cylinders. Refer to the following Tables for the piston part numbers and the corresponding retainer clip for each cylinder pack. Each cylinder pack with multiple designed pistons uses the same rings, rods, and pins as the previous piston.

Note: The 325-9492 Piston Body As or the 10R-9611 Cylinder Pack As must not be used any other piston or cylinder pack. The 325-9492 Piston Body As is heavier than the 356-4787 Piston Body must not be mixed within the engine, and must be used in sets of six.

Refer to the following Tables for the piston part numbers, and the corresponding cylinder packs.

Illustration 3	g02616200
Proper orientation of retainer (A) 45 degrees

The retainer, and the requirement for retainer orientation can vary. The opening of the retainer can be installed 45 degrees in either direction from the vertical position. Refer to Illustration 3.