3406E, C12, C15 and C18 Marine Engines Caterpillar

Probable Causes

• Air inlet system or exhaust system

• Engine speed/timing sensors

• Valve lash

• Electronic unit injector

• Intake manifold (boost) pressure sensor, rated fuel position and/or FRC fuel position

• Flash file

• Fuel quality

Recommended Actions

Air Inlet System or Exhaust System

1. Check the air inlet system for restrictions and/or for leaks.

   1. Check for an air filter restriction.

   2. Check for derates and for alarms.

   3. Perform a visual inspection of the system for restrictions and/or for leaks.

2. Ensure that the turbocharger has not failed.

3. Check the exhaust system for restrictions.

4. Repair any leaks that were found. Remove any restrictions that were found. Replace any damaged components that were found.

Engine Speed/Timing Sensors

1. Check the calibration of the engine speed/timing sensor. Refer to calibration procedures Troubleshooting, "Engine Speed/Timing Sensor - Calibrate".

2. Verify that the crankshaft and the camshaft drive gears are set with the proper orientation. Refer to the Disassembly and Assembly manual.

Valve Lash

Check the valve lash. Refer to Systems Operation/Testing and Adjusting.

Electronic Unit Injector

1. Ensure that the electronic unit injector connectors (J300/P300) are fully connected and free of corrosion.

2. Ensure that the ECM connector (J2/P2) is fully connected and free of corrosion.

3. Connect the Caterpillar Electronic Technician (ET). Run the cylinder cutout test in order to identify any misfiring cylinders.

   Refer to the diagnostic functional test Troubleshooting, "Injector Solenoid Circuit - Test".

Intake Manifold (Boost) Pressure Sensor, Rated Fuel Position and/or FRC Fuel Position

1. 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 Electronic Control Module (ECM) is providing the correct control. Otherwise, proceed to the next Step.

2. Verify that there are no active diagnostic codes.

3. Monitor the status of "Intake Manifold (Boost) Pressure" and "Atmospheric Pressure" on the Caterpillar Electronic Technician (ET). When the engine is not running, "Boost Pressure" should be 0 kPa (0 psi).

   Note: A problem with the FRC will only cause black smoke during acceleration. A problem with the FRC will not cause black smoke during steady state operation.

Flash File

Verify that the correct flash file is installed. Refer to programming parameters Troubleshooting, "Flash Programming".

Fuel Quality

1. Check fuel quality.

2. Cold weather adversely affects the characteristics of the fuel. For information on improving the characteristics of the fuel during cold weather operation, refer to the Operation and Maintenance Manual.