ELBOW 0337625 - Caterpillar

Probable Causes
Diagnostic codes
Flash file
Coolant temperature sensor circuit
Low coolant temperature
Starting Aid
Fuel quality
Valve lash
Low compression (cylinder pressure)
Individual malfunctioning cylinderRecommended Actions
Diagnostic Codes
Use the electronic service tool in order to check for active diagnostic codes and/or check for logged diagnostic codes. Troubleshoot any active codes before continuing with this procedure.
If the problem has not been eliminated, proceed to "Flash File". Flash File
Verify that the correct flash file is installed. Refer to Troubleshooting, "Flash Programming".
If the problem has not been eliminated, proceed to "Coolant Temperature Sensor Circuit". Coolant Temperature Sensor Circuit
Connect the electronic service tool to the diagnostic connector.
Monitor the display screen on the electronic service tool in order to verify the presence of active diagnostic codes for the coolant temperature. Refer to Troubleshooting, "Engine Temperature Sensor Open or Short Circuit - Test".
If the problem has not been eliminated, proceed to "Low Coolant Temperature". Low Coolant Temperature
Check that the water temperature regulator is operating correctly. Refer to Testing and Adjusting, "Water Temperature Regulator - Test".If the water temperature regulator is operating correctly, refer to "Starting Aid".Starting Aid
Check for proper operation of the starting aid. Refer to Troubleshooting, "Ether Injection System - Test".
If the repairs do not eliminate the fault refer to "Fuel Quality". Fuel Quality
Check the diesel fuel for quality. Refer to Testing and Adjusting, "Fuel Quality - Test". Note: Diesel fuel with a low cetane value is likely to cause white smoke.
If the repair does not eliminate the fault refer to "Valve Lash". Valve Lash
Ensure that the valve lash is correct. Refer to Testing and Adjusting, "Engine Valve Lash - Inspect/Adjust".
If the repair does not eliminate the fault proceed to "Low Compression (cylinder pressure)". Low Compression (cylinder pressure)
Perform a compression test. Refer to Testing and Adjusting, "Compression - Test ".
If low compression is noted on any cylinders, investigate the cause and rectify the cause. Possible causes of low compression are shown in the following list:
Loose blanking plugs in the cylinder head.
Faulty piston
Faulty piston rings
Worn cylinder bores
Worn valves
Faulty cylinder head gasket
Damaged cylinder head
Perform all necessary repairs.
Ensure that the repairs have eliminated the faults.
If the repair does not eliminate the fault refer to "Individual Malfunctioning Cylinder". Individual Malfunctioning Cylinder
With the engine speed at a fast idle, use the electronic service tool to isolate one cylinder at a time. Note if there is any reduction in engine speed. If a reduction in engine speed is not noted, the isolated cylinder is not operating under normal conditions. If the isolation of a particular cylinder results in a reduction of engine speed that is less than normal, this may indicate that the cylinder is operating below normal performance. Investigate the cause of the fault on any cylinder that is not operating. Investigate the cause of the fault on any cylinder that is operating below normal performance.
Rectify any faults.