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Home >> GMC >> 2002 >> C3500 HD 8.1 G, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 8.1L >> Repair Instructions >> Spark Plug Replacement >> Installation Procedure
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Installation Procedure

  1. Properly position each spark plug washer.
  2. Inspect each spark plug gap. Adjust each plug as needed.

    Specification

    Spark plug gap: 1.524 mm (0.060 in)

    NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
  3. Install the spark plugs.

    Tighten 

    • For (IRON Head-all Subsequent Installations) tighten the spark plugs to 20 N.m (15 lb ft).
    • For new iron heads tighten the spark plugs to 30 N.m (22 lb ft).
  4. Install the spark plug wires. Refer to Spark Plug Wire Replacement .
    Fig 1: Spark Plug
    G01599006Courtesy of GENERAL MOTORS CORP.