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Engine Block Plug Installation

Tools Required 

J 41712  Oil Pressure Switch Socket

  1. Install a NEW oil filter bypass valve.
    1. 1.1. Install the oil filter bypass valve into the oil gallery bore until slightly below flush with the surface of the engine block.
    2. 1.2. Using a pointed punch, stake the engine block area around the oil filter bypass valve. Stake in 3 locations 120 degrees apart.
      Fig 1: Oil Filter Bypass Valve
      G02503022Courtesy of GENERAL MOTORS CORP.
  2. Apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the outside diameter of the NEW front engine oil gallery plugs.
  3. Install the NEW front engine block oil gallery plugs. A properly installed front engine oil gallery plug must be installed slightly below flush with the front face of the engine block.
    Fig 2: Front Engine Block Oil Gallery Plugs
    G02503023Courtesy of GENERAL MOTORS CORP.
  4. Apply threadlock GM P/N United States 12345382, GM P/N Canada 10953489, or equivalent, to the outside diameter of the NEW engine block core hole plugs.
  5. Install the NEW engine block core hole plugs. A properly installed engine block core hole plug must be installed flush or below the bottom of the chamfer (1) of the engine block core hole.
    Fig 3: Engine Block Core Hole Plugs
    G02503024Courtesy of GENERAL MOTORS CORP.
  6. Install the crankshaft rear oil seal housing locator spring type S pin, if required.
    Fig 4: Crankshaft Rear Oil Seal Housing Locator Spring Type S Pin
    G02503025Courtesy of GENERAL MOTORS CORP.
  7. Apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the outside diameter of the NEW expansion cup plug.
  8. Install the NEW expansion cup plug into the balance shaft rear bearing hole.
    Fig 5: Balance Shaft Rear Bearing Hole Expansion Cup Plug
    G02503026Courtesy of GENERAL MOTORS CORP.
  9. Apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the outside diameter of the NEW expansion cup plug.
  10. Install the NEW expansion cup plug into the camshaft rear bearing hole.
    Fig 6: Camshaft Rear Bearing Hole Expansion Cup Plug
    G02503027Courtesy of GENERAL MOTORS CORP.
  11. Apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the threads of the engine block right rear oil gallery plug, the engine block left rear oil gallery plug, and the engine block left side oil gallery plug.
  12. Install the engine block right rear oil gallery plug, the engine block left rear oil gallery plug, and the engine block left side oil gallery plug.
    • Tighten the engine block left side oil gallery plug and the engine block right rear oil gallery plug to 20 N.m (15 Lb ft).
    • Tighten the engine block left rear oil gallery plug to 30 N.m (22 Lb ft).
      Fig 7: Engine Block Right & Left Rear Oil Gallery Plugs
      G02503028Courtesy of GENERAL MOTORS CORP.
  13. Install the transmission locator dowel straight pins, if required.
    Fig 8: Transmission Locator Dowel Straight Pins
    G02503029Courtesy of GENERAL MOTORS CORP.
  14. Install the left side cylinder head locator dowel pins, if required.
    Fig 9: Left Side Cylinder Head Locator Dowel Pins
    G02503030Courtesy of GENERAL MOTORS CORP.
  15. Install the right side cylinder head locator dowel pins, if required.
    Fig 10: Right Side Cylinder Head Locator Dowel Pins
    G02503031Courtesy of GENERAL MOTORS CORP.
  16. Apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the threads of the engine block coolant drain hole plugs.
  17. Install the engine block coolant drain hole plugs. Tighten the engine block coolant hole plugs to 20 N.m (15 lb ft).
    Fig 11: Engine Block Coolant Drain Hole Plugs
    G02503032Courtesy of GENERAL MOTORS CORP.
  18. If reusing the engine oil pressure sensor fitting, apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the threads of the engine oil pressure sensor fitting.
    Fig 12: Engine Oil Pressure Sensor Fitting
    G02503033Courtesy of GENERAL MOTORS CORP.

    Important:  Do not loosen the engine oil pressure fitting after the initial torque has been obtained.

  19. Install the engine oil pressure sensor fitting. Tighten the engine oil pressure sensor fitting to 15 N.m (11 Lb ft).

    Important:  Do not rotate the engine oil pressure fitting clockwise more than 359 degrees after the initial torque has been obtained.

  20. Rotate the engine oil pressure sensor fitting clockwise to the proper position (1), 50 degrees from the centerline (2).
  21. If reusing the engine oil pressure gage sensor, apply sealant GM P/N United States 12346004, GM P/N Canada 10953480, or equivalent, to the threads of the engine oil pressure gage sensor.
  22. Install the engine oil pressure gage sensor using the J 41712. Tighten the engine oil pressure gage sensor to 30 N.m (22 Lb ft).
    Fig 13: Engine Oil Pressure Gage Sensor
    G02503034Courtesy of GENERAL MOTORS CORP.
  23. Install the knock sensor (2).
  24. Install the knock sensor retaining bolt (1). Tighten the knock sensor to 25 N.m (18 Lb ft).
    Fig 14: Knock Sensor
    G02503035Courtesy of GENERAL MOTORS CORP.