Glow Plug Replacement Inspection

The glow plugs can be tested in two ways:

•

Take an amperage draw test with an inductive pick-up 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 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.

Glow Plug Replacement Replacement

1. Tilt the cab. Refer to Strategy Based Diagnosis in General Information.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

2. Disconnect the negative battery cables.
3. Disconnect the glow plug power supply wire.
4. Disconnect the glow plug buss bar.
5. Remove the glow plugs from the cylinder head.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

1. Install the glow plugs to the cylinder head.

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 (11 lb in).

3. Connect the glow plug power supply wire.
4. Connect the negative battery cables.
5. Lower the cab.