Crankshaft Rear Oil Seal Removal

Tools Required 

J 42841-A Rear Oil Seal Remover

IMPORTANT:

Although originally equipped with a lip-style crankshaft rear oil seal, engines built from March 1, 1996 and thru 1999 should now use the cassette-style crankshaft rear oil seal.

IMPORTANT:

If the engine is in the vehicle, the crankshaft rear oil seal can be removed/installed after the transmission/transaxle and engine flywheel are removed.

IMPORTANT:

Crankshaft rear oil seal removal requires adequate space for removal. Mount the engine on a suitable engine stand which will properly space the engine in order to use the J 42841-A in order to remove the crankshaft rear oil seal. If necessary, remove the crankshaft rear oil seal with the engine properly supported on the floor or on a bench.

IMPORTANT:

Beginning with the model year 2006 the flywheel/flexplate crankshaft bolt hole thread was changed from 8 x 1.25 mm to 11 x 1.5 mm. The J 42841-A will service the cassette seals installed on engines from March 1, 1996 and later. If the older J 42841 is to be used on a 2006 or later engine the update kit, J 42841-10, must be used to convert the J 42841 to a J 42841-A .

Fig 1: Rear Oil Seal Remover Plate & Retaining Bolts
Courtesy of GENERAL MOTORS COMPANY
1. Install the J 42841-A plate onto the crankshaft. The hub on the crankshaft will fit into the recess on the inboard side of the J 42841-A plate.
Fig 2: Identifying Crankshaft Rear Oil Seal Remover & Components
Courtesy of GENERAL MOTORS COMPANY
IMPORTANT:

Northstar engines 2005 and older have an 8 x 1.25 mm flywheel/flexplate crankshaft bolt hole thread. Northstar engines 2006 and later have an 11 x 1.5 mm flywheel/flexplate crankshaft bolt hole thread.

2. Use the proper bolts from the J 42841-A to retain the plate in place. Use the bolts (1) 8 mm or the bolts (2) 11 mm.
Fig 3: Placing Screws into Seal
Courtesy of GENERAL MOTORS COMPANY
3. Using a drill motor, variable speed preferred, with a socket adapter, install eight 25 mm (1.0 in) self-drilling screws into the seal using the guide holes in the removal tool. When drilling, ensure the drill motor speed is reduced when the screw begins threading into the seal.
Fig 4: View of Rear Oil Seal Remover Plate & Retaining Bolts
Courtesy of GENERAL MOTORS COMPANY
4. With all eight removal screws installed, remove the J 42841-A retaining bolts.
Fig 5: Rear Oil Seal Remover Plate & Center Forcing Screw
Courtesy of GENERAL MOTORS COMPANY
5. Install the center forcing screw.
Fig 6: Rear Oil Seal Remover Plate
Courtesy of GENERAL MOTORS COMPANY
6. Tighten the center screw on the J 42841-A in order to pull the seal assembly off the end of the crankshaft.
Fig 7: Identifying Rear Crankshaft Seal Bore & Flange
Courtesy of GENERAL MOTORS COMPANY
7. After removing the crankshaft rear oil seal inspect the engine block bore (1) and the crankshaft flange (2) for the damage. Repair or replace any damaged components.