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Home >> Chevrolet >> 2004 >> Astro Van Cargo, AWD >> Repair and Diagnosis >> Engine Mechanical >> Engine Mechanical - 4.3L >> Repair Instructions >> Off-Vehicle Repair Instructions >> Engine Block Plug Installation >> Installation Procedure
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Installation Procedure

CAUTION: Refer to Safety Glasses Caution in Cautions and Notices.
  1. Install a NEW oil filter bypass valve.
    1. Install the oil filter bypass valve into the oil gallery bore until slightly below flush with the surface of the engine block.
    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: Cross Section View Of Oil Filter Bypass Valve
    GM188023Courtesy of GENERAL MOTORS CORP.
  2. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the outside diameter of the NEW front engine oil gallery plugs.
    Fig 2: Identifying Front Oil Gallery Plugs Or Balls
    GM5270Courtesy of GENERAL MOTORS CORP.
  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.

  4. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489) or equivalent, to the outside diameter of the NEW engine block core hole plugs.
    Fig 3: Expanded View Of Engine Block Core Hole Plugs
    GM480572Courtesy of GENERAL MOTORS CORP.
  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.

  6. Install the crankshaft rear oil seal housing locator spring type S pin, if required.
    Fig 4: Locating Crankshaft Rear Oil Seal Housing Locator Spring Type S Pin
    GM334546Courtesy of GENERAL MOTORS CORP.
  7. Apply sealant GM P/N 12346004 (Canadian P/N 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: Identifying Balance Shaft Rear Bearing Hole Expansion Cup Plug Measurements
    GM334540Courtesy of GENERAL MOTORS CORP.
  9. Apply sealant GM P/N 12346004 (Canadian P/N 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: Checking Camshaft Rear Bearing Hole Expansion Cup Plug Dimensions
    GM334543Courtesy of GENERAL MOTORS CORP.
  11. Apply sealant GM P/N 12346004 (Canadian P/N 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.
    Fig 7: View Of Oil Gallery Plugs
    GM5271Courtesy of GENERAL MOTORS CORP.
    NOTE: Refer to Fastener Notice in Cautions and Notices.
  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: 

    • 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).

  13. Install the transmission locator dowel straight pins, if required.
    Fig 8: Proper Transmission Locator Dowel Straight Pins Installation
    GM334548Courtesy of GENERAL MOTORS CORP.
  14. Install the left side cylinder head locator dowel pins, if required.

    The installation height should be 6.3-6.5 mm (0.248-0.256 in) (a).

    Fig 9: Correct Installation Height Of Left Side Cylinder Head Locator Dowel Pins
    GM859876Courtesy of GENERAL MOTORS CORP.
  15. Install the right side cylinder head locator dowel pins, if required.

    The installation height should be 6.3-6.5 mm (0.248-0.256 in) (a).

    Fig 10: Measuring Right Side Cylinder Head Locator Dowel Pins Installation Height
    GM859879Courtesy of GENERAL MOTORS CORP.
  16. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the threads of the engine block coolant drain hole plugs.
  17. Install the engine block coolant drain hole plugs.

    Tighten:  Tighten the engine block coolant hole plugs to 20 N.m (15 lb ft).

    Fig 11: Removing Engine Block Coolant Drain Hole Plugs
    GM188052Courtesy of GENERAL MOTORS CORP.
  18. If reusing the engine oil pressure sensor fitting, apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent, to the threads of the engine oil pressure sensor fitting.
    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:  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).
    Fig 12: Identifying Correct Engine Oil Pressure Sensor Fitting Position
    GM334549Courtesy of GENERAL MOTORS CORP.
    21. Fig 13: Identifying J 41712
    GM188018Courtesy of GENERAL MOTORS CORP.
  21. If reusing the engine oil pressure gage sensor, apply sealant GM P/N 12346004 (Canadian P/N 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:  Tighten the engine oil pressure gage sensor to 30 N.m (22 lb ft).

  23. Install the knock sensor (2).
  24. Install the knock sensor retaining bolt (1).

    Tighten:  Tighten the knock sensor to 25 N.m (18 lb ft).

    Fig 14: Locating Knock Sensor & Retaining Bolt
    GM679284Courtesy of GENERAL MOTORS CORP.
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