Crankshaft Rear Oil Seal Installation

Special Tools

• EN-48072:  Sealant Applicator
• J 38817-A:  Rear Main Seal Installer
• J 45930-A:  Crankshaft Rear Oil Seal Installer

  For equivalent regional tools, refer to Special Tools .

NOTE: The EN-48072:  applicator must be used to ensure even application of the sealant in the bore and to prevent blockage of the drain back hole.
NOTE: Ensure components that are being sealed with RTV sealant are assembled within 20 minutes. Components assembled after the RTV sealant has skinned-over, approximately 20 minutes, will not bond properly.
Fig 1: Oil Seal Bore Depth
Courtesy of GENERAL MOTORS CORP.
1. Ensure the engine block where the crankshaft rear oil seal is installed is a deep bore (1).
   • A deep bore of approximately 15 mm (0.5906 in) was used on engines from March 1, 1996 and later.
   • A shallow bore of approximately 8 mm (0.3150 in) was used on engines from 1993 thru February 29, 1996. This block would use a lip-style crankshaft rear oil seal and the J 38817-A:  installer for installation.
Fig 2: Engine Block Bore & Crankshaft Flange
Courtesy of GENERAL MOTORS CORP.
2. Inspect the engine block bore (1) and the crankshaft flange (2) for the damage. Repair or replace any damaged components.
Fig 3: Oil Drain-Back Hole
Courtesy of GENERAL MOTORS CORP.
3. Ensure the oil drain-back hole (1) is clear of debris using a wire (2) or an unbound plastic tie wrap.
Fig 4: Cleaning Bore
Courtesy of GENERAL MOTORS CORP.
NOTE: In order to ensure proper bonding of the sealant the bore must be clean and dry.
4. Clean the bore in the block with cleaner solvent GM P/N 12378392 or 12346139 (Canadian P/N 88901247).
Fig 5: J 45930-A Tool Set
Courtesy of GENERAL MOTORS CORP.
NOTE: 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.
5. Remove the proper sized bolts from the J 45930-A:  installer. Use the bolts (2) 8 mm or the bolts (3) 11 mm.
Fig 6: EN-48072
Courtesy of GENERAL MOTORS CORP.
6. Install the EN-48072:  applicator pilot base onto the crankshaft. The hub on the crankshaft will fit into the recess on the inboard side of the EN-48072:  applicator pilot base.
Fig 7: J 45930-A
Courtesy of GENERAL MOTORS CORP.
NOTE: 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.
7. Use the proper bolts from the J 45930-A:  installer to retain the EN-48072:  applicator pilot base in place.
Fig 8: EN-48072
Courtesy of GENERAL MOTORS CORP.
8. Install the EN-48072:  applicator applicator housing over the EN-48072:  applicator pilot base. Ensure the EN-48072:  applicator applicator housing bottoms in the bore of the block.
Fig 9: Applying Sealant
Courtesy of GENERAL MOTORS CORP.
NOTE: The sealant must not block the drain back hole. Blockage of the drain back hole can lead to oil leakage.
9. Apply the sealant GM P/N 12378521 (Canadian P/N 88901148) to the bore outer diameter in the block. Ensure the sealant does not block the drain hole.
Fig 10: Spreading Sealant
Courtesy of GENERAL MOTORS CORP.
NOTE: Apply steady even pressure to the EN-48072:  applicator applicator housing.
10. Using a suitable tool spread the sealant within the bore to ensure an even coating across the bore.
Fig 11: Removing EN-48072
Courtesy of GENERAL MOTORS CORP.
NOTE: In order to apply an even coat of the sealant do not twist or turn the EN-48072:  applicator applicator housing as it is pulled away from the bottom of the bore.
11. Using both hands, slowly and evenly, pull the EN-48072:  applicator applicator housing out of the bore and remove it from the EN-48072:  applicator pilot base.
Fig 12: J 45930-A
Courtesy of GENERAL MOTORS CORP.
12. Remove the J 45930-A:  installer bolts from the EN-48072:  applicator pilot base.
Fig 13: EN-48072
Courtesy of GENERAL MOTORS CORP.
13. Remove the EN-48072:  applicator pilot base.
Fig 14: Sealant Application
Courtesy of GENERAL MOTORS CORP.
14. Ensure that the sealant (1) is evenly spread across the bore of the block.
Fig 15: Drain Back Hole
Courtesy of GENERAL MOTORS CORP.
15. Ensure the drain back hole (1) is clear of the sealant.
CAUTION: The cassette seal is installed onto the crankshaft with a press fit that requires over 135 Nm (100 lb ft) of force to remove or install. This high force requires the use of special tools to remove and install the seal. Use of any other tools during removal or installation can lead to damage to the seal or other components. An improperly installed or damaged seal can leak oil and can lead to engine damage. Use of the J 38817-A to install the cassette seal can damage the tool and cause improper seal installation and/or seal damage.
NOTE: 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 45930-A:  installer will service the cassette seals installed on engines from March 1, 1996 to 2006. If a J 45930 is to be used on a 2006 or later engine the update kit, J 45930-10, must be used to convert the J 45930 to a J 45930-A:  installer.
NOTE: Crankshaft rear oil seal and engine flywheel installation requires adequate space for installation. If the engine stand does not allow suitable space to use the J 45930-A:  installer install the crankshaft rear oil seal and engine flywheel with the engine properly supported on the floor or on a bench.
Fig 16: J 45930-A Tool Set
Courtesy of GENERAL MOTORS CORP.
NOTE: 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.
16. Ensure the proper size of bolt (2) 8 mm or (3) 11 mm is being installed in the J 45930-A:  installer.
Fig 17: Crankshaft Rear Oil Seal Installer
Courtesy of GENERAL MOTORS CORP.
17. Turn the center nut (1) of the J 45930-A:  installer until the center hub (2) protrudes approximately 15 mm (0.591 in) beyond the outer plate (3).
Fig 18: Rear Seal Lubrication Points
Courtesy of GENERAL MOTORS CORP.
NOTE: DO NOT use any lubricant in order to install the crankshaft rear oil seal. Do not use any lubricant on the coating pre-applied to the inner diameter of the crankshaft rear oil seal. The coating is a sealant that must not be contaminated. Do not use any lubricant on the outer diameter of the crankshaft rear oil seal. The sealant applied to the bore of the engine block will not properly bond to a lubricated crankshaft rear oil seal.
18. Do not lubricate any part of the new cassette style crankshaft rear oil seal.
Fig 19: Cassette Style Crankshaft Rear Oil Seal
Courtesy of GENERAL MOTORS CORP.
19. Install the new cassette style crankshaft rear oil seal onto the center hub of the J 45930-A:  installer.
Fig 20: J 45930-A
Courtesy of GENERAL MOTORS CORP.
20. Thread the two J 45930-A:  installer mounting bolts into the crankshaft flywheel bolt holes.
Fig 21: Tightening Mounting Bolts
Courtesy of GENERAL MOTORS CORP.
21. Tighten the two mounting bolts until the J 45930-A:  installer is firmly mounted on the crankshaft.
Fig 22: Tightening Nut On J 45930-A
Courtesy of GENERAL MOTORS CORP.
22. Install the new cassette style crankshaft rear oil seal by turning the nut of the J 45930-A:  installer until the drive portion of the J 45930-A:  installer bottoms against the crankcase.
Fig 23: Releasing Pressure On Crankcase
Courtesy of GENERAL MOTORS CORP.
23. Loosen the center nut to release pressure on the crankcase.
Fig 24: Loosening Mounting Bolts
Courtesy of GENERAL MOTORS CORP.
24. Loosen the two mounting bolts.
Fig 25: J 45930-A
Courtesy of GENERAL MOTORS CORP.
25. Remove the J 45930-A:  installer from the crankshaft.
26. Wipe off any excessive sealant from the block.
Fig 26: Crankshaft Rear Oil Seal
Courtesy of GENERAL MOTORS CORP.
27. Ensure the new cassette style crankshaft rear oil seal is installed properly.
    • The outer surface of the seal (3) should be 0.500-0.800 mm (0.0197-0.0315 in) (1) below the surface of the engine block (2).
    • The inner surface of the sleeve (6) should be 0.400-0.900 mm (0.0158-0.0354 in) (4) below the surface of the outer surface of the seal (5).
    • The installed seal and sleeve need to be parallel to the block by 0.000-0.500 mm (0.000-0.0197 in).
28. Clean all tools to remove any residual sealant.