- Excessive load
- Excessive inlet air pressure
- High inlet air temperature
- Incorrect air/fuel ratio
- Incorrect base timing
- Changes in the fuel quality
- The engine speed/timing sensor is not calibrated.
- Faulty circuit for the detonation sensor(s)
- Excessive deposits in the combustion chamber
Make sure that the load is not excessive. Reduce the load. If necessary, disengage the driven equipment and test the engine.
The calculated engine load increases when the inlet air pressure increases. Measure the inlet air pressure during engine operation with a load. For specific data on the engine, refer to the engine Technical Marketing Information.
Check the Inlet Air Temperature
High inlet air temperature can cause detonation. Check the inlet air temperature. Look for the following event codes:
- "E026 (3) High Inlet Air Temperature" (shutdown)
- "E027 (1) High Inlet Air Temperature" (warning)
Refer to Troubleshooting, "Inlet Air Temperature (High)".
An air/fuel mixture that is too rich will cause detonation. Verify that the exhaust emissions are correct. Refer to Systems Operation/Testing and Adjusting, "Air/Fuel Ratio Control - Adjust".
A change in the fuel energy content will change the air/fuel ratio. Obtain a fuel analysis.
The fuel supply pressure must be adequate and stable.
Make sure that the fuel metering valve is operating correctly.
Verify that the base timing is correct. Refer to Systems Operation/Testing and Adjusting, "Ignition Timing - Adjust".
Check for Event Codes Regarding the Fuel
Check for the following event codes:
- "E229 (1) Fuel Energy Content Setting Low" (warning)
- "E230 (1) Fuel Energy Content Setting High" (warning)
- "E231 (3) Fuel Quality Out Of Range" (shutdown)
Refer to Troubleshooting, "Fuel Energy Content".
Calibrate the Engine Speed/Timing Sensor
Note: Only perform this procedure if work on the engine may have affected the engine timing. Also, perform this procedure if the engine speed/timing sensor has not been calibrated.
Refer to Troubleshooting, "Engine Speed/Timing Sensor - Calibrate".
Troubleshoot the detonation sensors. Refer to Troubleshooting, "Detonation Sensors".
Check for Deposits in the Cylinders
Overfilling of engine oil can lead to deposits. Make sure that the engine oil level is correct.
Note: Excessive deposits contribute to guttering of the valves.
Use a borescope to inspect the cylinders. Look for the following conditions:
- Deposits on the valve seats
- Deposits on the valve faces
- Deposits on the cylinder walls that are above the upper limit of the piston stroke
- Signs of internal leaks
Signs of internal leaks include excessive consumption of engine oil, blue smoke, and excessive detonation.
If excessive deposits and/or signs of internal leaks are found, investigate the cause of the condition. Make repairs, as needed.