COVER AS-SOUND SUPPRESSION 3992560 - Caterpillar

and 3400 Series Engines;
D379, D398, D399 EnginesDescription of Change: The seal groups, used for parts replacement of the water pump impeller seal on the above models, now have all of the parts that are needed for seal replacement. Formerly, it was necessary to order the seal assembly, ring and seal separately. Also, installation tools have been added to the seal groups. The purpose of the installation tools is to put the seal parts in the correct position during assembly. Seals that are assembled with seal parts in the wrong position can have early failures. Also, the installation tools make installation of the seals easier and faster. The installation tools can not be ordered separately.Adaptable As: Direct replacement. INSTALLATION:
Use clean water only as a lubricant to make the installation of the seal easier.1. Install the shaft, bearings and the oil seal. See the Service Manual.2. Use the installation tool to install the seal and ring. Use hand pressure only. See Illustration 2.3. Remove the spring from the seal assembly. Install the seal assembly with the installation tool until the seal assembly makes light contact with the ring. Use hand pressure only. See Illustration 3.4. Install the spring and impeller. See the Service Manual.
Illustration 1. Water pump impeller seal.
Illustration 2. Installation of seal and ring.
Illustration 3. Installation of seal assembly.