BLOCK 1F5448 - Caterpillar

Do not use the 7N3083 Cylinder Head Gaskets or the 7N5681 Cylinder Liners in engines that have the former cylinder block. This can cause a failure of the cylinder head gasket and engine damage.
Chart 2 shows the parts needed to install the new cylinder block in an engine that had the former cylinder block. Since the former cylinder block is canceled, the new parts will be sent if the former cylinder block is ordered. Always give the engine serial number and engine arrangement number when you order parts from Chart 2. See notes about the cylinder liners and the timing gear housing after Chart 2.
When the new cylinder block is installed in an engine that had the former cylinder block, it is not necessary to use the new 7N5681 Cylinder Liners if the former liners can be used again and are inspected as follows to see that there is an acceptable seal between the cylinder liners and the cylinder head gasket.1) Look at the top and side surfaces of the liner flanges. If there are any dents (damage caused by impact) or nicks (small pieces of material removed) in the top or side surfaces of the liner flange, the cylinder liner can not be used with the new cylinder block.2) Install the cylinder liners in the cylinder block. Put the cylinder head gasket on the top of the cylinder block. If any of the openings for the cylinders in the cylinder head gasket are not centered (equal gap between the gasket and liner all around the circumference) on the top surface of the cylinder liner, that cylinder liner can not be used with the new cylinder block.
The failure to inspect the parts as shown above can cause a failure of the cylinder head gasket and engine damage.
When the new cylinder block is installed in an engine that had the former cylinder block, it is not necessary to use the new timing gear housing. It is necessary to make modifications to the former timing gear housing to use it with the new cylinder block. The instructions to make the modifications follow:Procedure To Make Modifications To Timing Gear Housing
The top two holes in the former timing gear housings that were used to hold the timing gear housing to the cylinder block are higher than the top of the new cylinder block. These two holes must be plugged (filled so they will not leak) and two new holes must be machined in lower positions. The procedure that follows gives instructions to do this.
1) Mark points A and B on the timing gear housing as shown in Illustration 1.2) Machine 1.500" (38.10) diameter holes at points A and B.3) Make 1 1/4" NPT threads in the two holes so that the end of a 1 1/4" solid pipe plug can be installed even with the face of the timing gear housing toward the cylinder block.
Illustration 1-Locations of points A and B. On most housings there may be part of casting openings that