SEAL-RECTANGULAR 5P3729 - Caterpillar

1693 Truck Engines ( 65B16248-up)Description of Change: Starting with Serial Number 65B16248, a new housing and a new impeller assembly were installed in the water pump and drive group to give improved cooling for 1693 Truck Engines. The vanes of the impeller assembly were extended .125" (3.17 mm) horizontally. The depth of the housing was increased .125" (3.17 mm) to give the necessary space for the new impeller assembly.Adaptable To: All earlier 1693 Truck Engines if both new parts are installed together.
If the 9N1864 Housing and 9N1863 Impeller Assembly are not installed together, the 1N9177 Seal Assembly can be damaged or there will be too much clearance between the impeller vanes and housing face. Either can cause overheating of the cooling system which can cause engine damage.
INSTALLATION: The clearance between the impeller vanes and housing face must be .005" to .015" (0.12 mm to 0.38 mm) after the nut is tightened to between 50 and 55 lb ft (70 and 75 N m). Hit the pulley end of the shaft with a soft (brass) hammer. Turn the impeller and check the clearance.