COVER GP-VALVE MECHANISM 2284216 - Caterpillar

If the engine is running, the ARD spark plug will continue to fire. Turn the key to the OFF position before servicing the ARD spark plug.
Disconnect the ignition wire from the ARD spark plug.
Connect the spark indicator between the ignition wire and the ARD spark plug.
The ignition system may cause an electrical shock hazard, which may cause personal injury or death. Avoid contacting the ignition system components and the ignition system wiring during operation.
Use the "ARD Ignition Transformer Primary Status" override on the electronic service tool to turn on the ARD ignition system.Expected Result:The spark indicator flashes.Results:
The spark indicator flashes. - Turn off the ARD ignition system by disabling the override. Proceed to Test Step 5.
The spark indicator does not flash. - Repair: Proceed to Troubleshooting, "ARD Ignition - Test".STOPTest Step 5. Clean the Components in the ARD Combustion Head
Illustration 3 g02401816
Use of the plug bore brush (1) ARD combustion head (2) Ground probe (3) 305-2389 Plug Bore Brush
If the engine is running, the ARD spark plug will continue to fire. Turn the key to the OFF position before servicing the ARD spark plug.
Remove the spark plug from the ARD combustion head.
Clean ground probe (2) inside ARD combustion head (1) by running 305-2389 Plug Bore Brush (3) through the hole in the ARD combustion head. Run the brush through the hole several times. Refer to Illustration 3.
Inspect the spark plug. Look for the following defects:Carbon Deposits - Use a nonmetallic cleaning pad to clean the spark plug.Bent Probe - Check the probe for damage.Damaged Insulator - Check the insulator for damage.Note: The spark plug may be damaged if the spark plug is dropped. Do not install a spark plug that has been dropped.Expected Result:The components are clean and the spark plug is not visibly damaged.Results:
Result 1: The components are clean and the spark plug is not visibly damaged. - Repair: Perform the following procedure:
Install the original spark plug.
The ignition system may cause an electrical shock hazard, which may cause personal injury or death. Avoid contacting the ignition system components and the ignition system wiring during operation.
Use the electronic service tool to perform an ARD ignition test.
Confirm that the fault has been eliminated.
If the fault is still present, install a replacement spark plug. Refer to Specifications, "Electronic Control Wiring Group (ARD)" for the correct torque value.
Use the electronic service tool to perform an ARD ignition test.
Confirm that the fault has been eliminated. If the fault is still present, install the original spark plug. Proceed to Test Step 6.
Result 2: The spark plug is damaged. - Repair: Perform the following procedure:
Install a replacement spark plug. Refer to Specifications, "Electronic Control Wiring Group (ARD)" for the correct torque value.
Use the electronic service tool to perform an ARD ignition test.
Confirm that the fault has been eliminated. If the fault is still present, proceed to Test Step 6.Test Step 6. Check the ARD Air SystemUse the electronic service tool to perform the ARD Air System Service Test.Results:
The ARD Air System Service Test