SHEET ASSEM. 6K3931 - Caterpillar

D379, D398, D399, G353, G379, G398, G399 EnginesIn the past, the 1P9 Connecting Rod Assemblies in the above engines have had two different sets of numbers put on them for identification purposes. One set of numbers was put on the rod and the cap before they were cut into two pieces. This was so that it was possible to keep the two pieces together as a set during manufacturing. This number can be any number 20 or more. The number on the rod was the same as the number on the cap.
It was found that it was not necessary to keep the rods and caps together as a set during all the steps in manufacturing. It was only necessary to keep them together after the final boring operation. Because of this, some of the rods and caps were mixed at the factory before the final boring operation.
Another set of numbers is put on the rod and cap assembly before it is installed in the engine. This set of numbers will be 1 through 16 and it will be the same number as the engine cylinder it is installed in.
These rods and caps with different numbers will not cause any problems as long as they have the same engine cylinder number on them, and they are both used in the correct cylinder.