The front crankshaft oil seal is mounted in the lower front cover. The rear oil seal is mounted in the flywheel housing. A wear sleeve in pressed fitted to the front of the crankshaft to provide a sealing surface for the front oil seal. The flywheel has a wear sleeve to provide a sealing surface for the rear oil seal. The sealing lips for front and rear seals are held in position against the crankshaft sealing surface by a spring. This prevents oil from escaping from the front crankshaft seal and rear wear sleeve on the flywheel. See Figure
1.Front Oil Seal
2.Lower Front Cover
5.Rear Oil Seal
Flywheel Housing, Crankshaft, Front Cover, Oil Seals
Repair or Replacement of Oil Seal
To determine if repair is possible or replacement is necessary, perform the following procedure. See Figure
Repair or Replacement of Crankshaft Oil Seal Flowchart
Removal of Crankshaft Oil Seal
The crankshaft oil seal is in the flywheel housing and the sleeve in on the flywheel. Any time the flywheel housing is removed, the crankshaft oil seal must be replaced. The crankshaft oil seal may have been damaged.
Crankshaft oil seal leaks may indicate worn or damaged oil seals. Oil seals may become worn or damaged because of improper installation, excessive main bearing clearances, excessive flywheel housing bore run-out, grooved seal surfaces on the crankshaft hubs, or out of square installation. To prevent recurring leaks, these conditions must be identified and corrected.
Inspect the crankshaft seal contact surface for wear and dirt. The contact surface must be clean and dry prior to wear sleeve and seal installation.