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For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2004 🢒 Isuzu MD F-Series 🢒 Engine 🢒 Engine Controls - 7.8L 🢒 Glow Plug Replacement

Glow Plug Replacement Without CTF

Glow Plug Inspection Procedure

The glow plugs can be tested in 2 ways:

   • 
Object Number: 736696 Size: SH
  • Take an amperage draw test with an inductive pick-up lead at each glow plug. The rated amp draw should be 6-7.5 amps per glow plug. Or install the inductive current clamp around the glow plug power supply wire. Take the systems current draw reading and divide the reading by the number of glow plugs in the system.
    •    • 
  • A continuity test can also be made with an ohmmeter between the glow plug lead and ground, with the buss bars removed. If no continuity exists, the glow plug will not heat and should be replaced.

    • Removal Procedure
    1. Tilt the cab. Refer to Strategy Based Diagnosis in General Information.
    2. Disconnect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
    3. Disconnect the glow plug power supply wire.
    4. Disconnect the glow plug buss bar.
    5. Remove the glow plugs from the cylinder head.

    Installation Procedure

      Notice: Refer to Fastener Notice in the Preface section.

    1. Install the glow plugs to the cylinder head.

      2. Tighten
      Tighten the glow plugs to 20 N·m (15 lb ft).

    2. Install the glow plug buss bar.

      3. Tighten
      Tighten the glow plug buss bar to 1 N·m (9 lb in).

    3. Connect the glow plug power supply wire.
    4. Connect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
    5. Lower the cab.

    Glow Plug Replacement With CTF

    Inspection Procedure

    The glow plugs can be tested in 2 ways:

       • 
  • Perform an amperage draw test with an inductive pickup lead at each glow plug. The rated amp draw should be 6.0-7.5 amps per glow plug. Or install the inductive current clamp around the glow plug power supply wire. Take the system's current draw reading and divide the reading by the number of glow plugs in the system.
    •    • 
    Object Number: 736696 Size: SH
  • A continuity test can also be made with an ohmmeter between the glow plug lead and ground with the buss bars removed. If no continuity exists, the glow plug will not heat and should be replaced.

    • Removal Procedure
    1. Tilt the cab. Refer to Cab Tilting in General Information.
    2. Disconnect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
    3. Disconnect the glow plug power supply wire.
    4. Disconnect the glow plug buss bar.
    5. Remove the glow plugs from the cylinder head.

    Installation Procedure

      Notice: Refer to Fastener Notice in the Preface section.

    1. Install the glow plugs to the cylinder head.

      2. Tighten
      Tighten the glow plugs to 20 N·m (15 lb ft).

    2. Install the glow plug buss bar.

      Tighten
      Tighten the glow plug buss bar to 1.2 N·m (10 lb in).

    3. Connect the glow plug power supply wire.
    4. Connect the negative battery cables. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
    5. Lower the cab.