C1.5 and C2.2 Engines for Caterpillar Built Machines Caterpillar

Illustration 1	g01109557
Typical example (1) Nut (2) Washer (3) Connector (4) Glow plug

Continuity Test

1. Connect the 8T-0500 Test Light between a ground and the terminal of the glow plug (4). Choose the glow plug that is farthest away from the battery. Turn the starting aid switch to the ON position.

   If the circuit is correct, the test light should turn on.

   If the test light does not turn on, inspect the circuit for loose connections, broken wires, and other damage.

2. Loosen the nut (1) on each glow plug and then disconnect the connectors (3) from the glow plugs (4).

3. Use the 6V-7070 Digital Multimeter to measure the resistance between the electrical terminal of the glow plug (4) and ground. The point for the ground should be as close to the glow plug as possible.

   Maximum resistance for the glow plugs. ... 1.0 ohm

4. Connect the test light to the positive terminal of the battery and to the electrical terminal of the glow plug (4). If the light turns on, the continuity in the glow plug is correct.

   If the light does not turn on, replace the glow plug.

   Repeat this step for each glow plug.

5. Install the connector (3) on each glow plug (4) and tighten the nut (1).

Glow Plug Circuit

1. Disconnect the power supply cable from the connector (3). Loosen the nut (1) and remove the connector (3) from the electrical terminal of the glow plug (4).

2. Connect the leads of a suitable ammeter between the power supply cable and the terminal of a glow plug and then connect the leads of the digital multimeter between the terminal of the glow plug and a ground. Turn on the starting aid switch. Observe the amperage reading of the ammeter and the voltage reading on the multimeter.

   C1.5, C2.2 NA and C2.2 Turbocharged

   Maximum current through the glow plug ... 11 A

   Current through the glow plug after 6 seconds ... 8.5 A

   The voltage should not drop more than 0.5 V.

   Perform step 2 for each glow plug.

3. If the multimeter reading is below the specified amperes, the glow plug should be replaced. If there is no reading, replace the glow plug.

   If the voltage reading of the multimeter is zero, inspect the starting aid switch and the power supply for faulty components and loose connections.

4. When the tests are complete, install the connector (3) to the terminal of each of the glow plugs (4) and tighten the nut (1). Connect the cable for the power supply to the glow plugs.