2010/02/22 Caterpillar

Engine:

C15 (S/N: KRA1-UP; TRB1-UP; JEP1-UP; SDP1-UP; MXS1-UP; NXS1-UP; RKS1-UP)

Truck Engine News SEBD6844, November 2010, "New Rocker Arm Assemblies Are Available on Some Truck Engines". Disregard this article see the article that follows.

There are two new castings for the rocker arms that are used in Caterpillar remanufactured rocker arm assemblies. Refer to the information below for the differences in the new rocker arm assemblies and existing rocker arm assemblies.

10R-3483 Rocker Arm As

The 243-2465 Rocker Arm and 286-1309 Rocker Arm are now allowed to be used in the 10R-3483 Rocker Arm As. The new 243-2465 Rocker Arm and the 286-1309 Rocker Arms are identical to the existing 274-5351 Rocker Arm in the fit and the function. The difference between the rocker arms is the adjustment screw and the jam nut. Refer to Table 1 and Table 2 for the components that are used with each rocker arm.

Table 1

New 243-2465 Rocker Arm and 286-1309 Rocker Arm

335-7396 Arm Adjustment Screw

9S-1354 Nut

Table 2

Existing 274-5351 Rocker Arm

196-5069 Arm Adjustment Screw

196-5070 Jam Nut

Illustration 1	g02110379
Possible rocker arms in the 10R-3483 Rocker Arm As (1) 274-5351 Rocker Arm (2) 196-5070 Jam Nut (3) 196-5069 Arm Adjustment Screw (4) 243-2465 Rocker Arm and 286-1309 Rocker Arm (5) 9S-1354 Nut (6) 335-7396 Arm Adjustment Screw

It is acceptable for the 243-2465 Rocker Arm, the 286-1309 Rocker Arm, and the 274-5351 Rocker Arm to be used together.

10R-4708 Rocker Arm As

The 259-6121 Valve Rocker Arm is now allowed to be used in the 10R-4708 Rocker Arm As. The new 259-6121 Valve Rocker Arm is identical to the existing 271-3962 Valve Rocker Arm in the fit and the function. The difference between the rocker arms is the adjustment screw and the jam nut. Refer to Table 3 and Table 4 for the components that are used with each rocker arm.

Table 3

New 259-6121 Valve Rocker Arm

335-7395 Screw

361-8756 Full Nut

Table 4

Existing 271-3962 Valve Rocker Arm

274-4491 Arm Adjustment Screw

276-5317 Nut

Illustration 2	g02110454
Possible rocker arms in the 10R-4708 Rocker Arm As (7) 271-3962 Valve Rocker Arm (8) 276-5317 Nut (9) 274-4491 Arm Adjustment Screw (10) 259-6121 Valve Rocker Arm (11) 361-8756 Full Nut (12) 335-7395 Screw

It is acceptable for the 259-6121 Valve Rocker Arm and the 271-3962 Valve Rocker Arm to be used together.

These new rocker arms were used as original equipment on the serial numbers that are listed in Table 5.

Table 5

Effective Serial Numbers

S/N:MXS1-UP

S/N:NXS1-8033