Starting System Operation Glow Plugs

Notice: Never manually spray starting aid fluids into the air intake where the fluid may come in contact with the heater element. This could result in an explosion and/or fire.

Diesel engines rely on the heat of compression in order to initiate combustion. Cold engine start-ups may require extra engine cranking time in order to create the necessary heat needed in order to ignite the diesel fuel.

Glow plugs are one of the devices available in order to aid in cold starting the diesel engine. Six glow plugs are used in order to preheat the combustion chambers as an aid to starting.

The glow plugs are 10.5 volt heaters that are operated at 12 volts when the engine control switch turns to the H position. The glow plugs provide a pre-heat feature to the combustion chamber. The glow plugs also improve cold weather engine start ups.

Starting System Operation Starting Procedure

Use the following procedure in order to initiate glow plug operation:

1. Turn the engine control switch to the H position.
2. Wait until the glow plug indicator glows.
3. Crank the engine.
4. Fully depress the accelerator pedal.
5. Release the accelerator pedal.
6. Turn the engine control switch to the START position.

Release the switch when the engine starts.

7. If the engine does not start after 15 seconds of cranking, repeat the procedure until the engine starts.

Starting System Operation Glow Plug Operation

Current flows through the following components when the engine control switch turns to the H position:

The current heats the glow plugs to 800°C (1472°F). The glow plugs take 20-25 seconds to heat when the ambient temperature is about 0°C (32°F).

The temperature of the control resistor heats at the same rate as the glow plugs. As the resistor temperature reaches 1000°C (1832°F) the resistor glows red. A glowing red resistor indicates the following conditions:

Inspect the components and the connections under the following conditions:

Refer to Control Resistor Check.