VALVE GP-CONTROL 3964879 - Caterpillar

Generator Set Engine (23Z, 70Z, 1ZF);
3512 Generator Set Engine (24Z, 67Z, 3YF);
3516 Generator Set Engine (25Z, 73Z, 4XF)Introduction
A service replacement cylinder block group is available for each of the engine models given above. Only one part number service replacement cylinder block group is used for each engine model.This instruction gives the procedure needed for the installation of a service replacement cylinder block group, according to the engine model and serial number prefix. The chart that follows gives the part number of the service replacement cylinder block group for each engine model. Installation
1. Depending upon the original engine model and the part number of the service replacement cylinder block group, [3508 (9Y6421), 3512 (7C6957) or 3516 (7C7754)], the cylinder block will have either one or two 4W4813 Plugs (1). These plugs are installed in specific holes within the cylinder block vee as shown in the illustration. 2. Each service replacement cylinder block group will also have, one or two 4W4814 Adapters (2) within the vee (see illustration above).These service replacement cylinder block groups, with 4W4813 Plugs (1) and 4W4814 Adapter(s) (2), can be used for the replacement of the cylinder block for 3508 (23Z, 70Z), 3512 (24Z, 67Z) or 3516 (25Z, 73Z) generator set engines. Adapters (2) are needed for installation of the aftercooler core on 3508 (23Z, 70Z), 3512 (24Z, 67Z), and 3516 (25Z, 73Z) engines. To install the aftercooler core from the former engine onto the new cylinder block, it is necessary to have the same number of adapters (2) on the new cylinder block as there were on the former cylinder block.
If the service replacement cylinder block group is to be used as a replacement for a 3508 (1ZF), 3512 (3YF) or 3516 (4XF) engine cylinder block, the 4W4814 Adapter(s) (2) must be removed. Install a 4W4813 Plug, with the necessary O-ring seals, as a replacement for each adapter that is removed.
3. To install a 4W4813 Plug (1), use the procedure that follows:* Remove the 4W4814 Adapter.* Install an 8T2928 O-ring Seal at location (A) on 4W4813 Plug (1).* Install an 8T2929 O-ring Seal at location (B) on 4W4813 Plug (1).* Install 4W4813 Plug (1). Tighten the plug to a torque of 100 15 N m (75 11 lb ft). The same part number O-ring seals are used on both the 4W4813 Plugs and the 4W4814 Adapters.
Aftercooler air chamber drain plug.4. For 3508 (1ZF), 3512 (3YF) or 3516 (4XF) engine cylinder block replacement ONLY, remove two 7H3171 Drain Plugs (3) (1/4"-18 hexagon countersunk head) as follows:One drain plug (3) is located between No. 1 and No. 3 cylinder heads on the right side of the engine. The other drain plug (3) that is to be removed is located between the last two cylinder heads on the left side of the engine.5. Refer to the engine Service Manual for additional assembly and specification information.