332-00021-1 Tohatsu PISTON PIN

Probable Causes
Diagnostic codes and event codes
Air inlet or exhaust system
Atmospheric pressure sensor
Intake manifold pressure sensor
Fuel quality
Low pressure fuel system
Valve lash adjustment
Gear train problem
Flash fileRecommended Actions
Diagnostic Codes and Event Codes
Connect Caterpillar Electronic Technician (ET) to the service tool connector. Check for active diagnostic codes and event codes.Look for diagnostic codes that are active or logged. Check for codes that are related to the high pressure fuel system, the low pressure fuel system, and the engine speed/timing circuit. Use the appropriate circuit test to troubleshoot any active codes before continuing.Also, look for event codes that are active or logged. check for codes that are related to the low pressure fuel system. If there is evidence of a problem with the fuel system, repair the low pressure fuel system before continuing.Note: Diagnostic codes that are logged repeatedly could be a sign of intermittent electrical problem. Event codes that are logged repeatedly may be evidence of an impending problem with the engine.Air Inlet or Exhaust System
Check the air inlet system for restrictions and/or for leaks.
Check for an air filter restriction.
Perform a visual inspection of the system for damage or restrictions. Also, inspect the air inlet system for air leaks in the piping.
Ensure that the turbochargers are in good repair.
Check the exhaust system for restrictions.
Repair any leaks that were found. Remove any restrictions that were found. Replace any damaged components that were found. Atmospheric Pressure Sensor
Check the atmospheric pressure sensor for dirt and/or for debris. Remove any dirt and/or debris that is present. The correct reading for the atmospheric pressure is between 50 kPa (7 psi) and 100 kPa (14 psi).Intake Manifold Pressure Sensor, "Fuel Position", and/or "FRC Fuel Limit"
Monitor the status of "Fuel Position" and "Rated Fuel Limit" while the engine is operating under full load. If "Fuel Position" equals "Rated Fuel Limit" and "Fuel Position" is less than "FRC Fuel Limit", the ECM is providing the correct control. Otherwise, proceed to the next Step.
Verify that there are no active diagnostic codes for the intake manifold pressure sensor.
Monitor the status of "Intake Manifold Pressure" and "Intake Manifold #2 Pressure" on Cat ET. When the engine is not running, "Intake Manifold Pressure" and "Intake Manifold #2 Pressure" should be approximately 0 kPa (0 psi). Note: A problem with the "FRC Fuel Limit" will only cause black smoke during acceleration. A problem with the "FRC Fuel Limit" will not cause black smoke during steady state operation.Fuel Quality
Check the fuel quality. For further information, refer to the engine's Operation and Maintenance Manual.Cold weather adversely affects the characteristics of the fuel. Refer to the Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold weather operation.Low Pressure Fuel System
Perform a visual inspection of the fuel system components.
Check the fuel pressure during engine cranking. Check the filtered fuel pressure. Refer to Systems Operation/Testing and Adjusting for the correct pressure values.
If the fuel pressure is OK, check for air in the fuel system. Refer to Systems Operation/Testing and Adjusting for details.
If the fuel pressure is low, replace the fuel filters. If the fuel pressure is still low, refer to Troubleshooting, "Fuel Pressure is Low" for more information that is related to troubleshooting the low pressure fuel system. Valve Lash Adjustment
Incorrect valve lash adjustment can be the cause of excessive black smoke in the engine exhaust. Refer to Systems Operation/Testing and Adjusting for information related to valve adjustments.Gear Train Problem
Verify that the crankshaft and the camshaft drive gears are set with the proper orientation for engine timing. Refer to the Disassembly and Assembly manual.Flash File
Verify that the latest flash file is installed. Refer to Troubleshooting, "ECM Software - Install" for information.