TURBOCHARGER GP 1055059 - Caterpillar

D11N, 776B Tractors;
777B, 785, 789 Trucks;
3500 Family Of EnginesReference: Special Instruction, SMHS8508, "Special Handling Information And Installation Instructions For Crankshaft Seal Groups That Have Hydrodynamic Grooves In The Sealing Lip".Description of Change: The adapters for the front and rear crankshaft seals are no longer used. The seals are now installed directly into a bore in the new front gear housing and new flywheel housing. This eliminates an O-ring seal joint and any risks for oil leaks past a damaged O-ring seal. The crankshaft seal part numbers did not change.
Adaptable To: The new 7W8055 Front Housing replaces the former 8N8300 Front Housing. The new 7W6444 Flywheel Housing replaces the former 7N3068 Flywheel Housing on the D11N and the 7W4095 Flywheel Housing on the 776B, 777B, 785, and 789. The effective PIN's for the new crankshaft seal and new housing groups are listed in Chart A.
The new 7W3376 and 7W1529 Front Housings replace the former 8N8300 Housing on their respective engine applications as shown in Chart B. The new 7W3721 and 2W7505 Flywheel Housings replace the 4W4922 Flywheel Housing on their respective applications as shown in Chart B.
Seal Installation
Special Instructions, Form SMHS8508, provides installation instructions for both the former and new style crankshaft seal arrangement.
Because the hydrodynamic grooves are very sensitive to the direction of crankshaft rotation, each seal is marked with an arrow to show the direction of shaft rotation for which the seal can be used. Also, the crankshaft seal and the wear sleeve are assembled together. If, during installation, there is separation of the seal and wear sleeve, do not reuse the seal group. Destroy the seal group and install a new seal group.