C9 Marine Auxiliary and Marine Generator Set Engines Caterpillar

Probable Causes

• Diagnostic codes

• Event codes

• Electrical power supply to the Electronic Control Module (ECM)

• Starting aids

• Engine shutdown switches

• Engine speed/timing

• Unit injectors

• Oil level

• Fuel supply

• Combustion problems

Recommended Actions

Diagnostic Codes and Event Codes

Certain diagnostic codes and/or event codes may prevent the engine from starting. Connect the Caterpillar Electronic Technician (ET) and check for active codes and/or for logged codes. Troubleshoot any codes that are present before continuing with this procedure.

Electrical Power Supply to the ECM

If the ECM is not receiving battery voltage, the ECM will not operate. Refer to Troubleshooting, "Electrical Power Supply Circuit - Test".

Starting Aids (if equipped)

If cold ambient conditions exist, check operation of starting aids. Verify that the air inlet heater is operating correctly. Refer to Troubleshooting, "Air Inlet Heater Circuit - Test".

Engine Shutdown Switches

The engine shutdown switches must be in the OFF position in order to start the engine. Use Cat ET to verify the status of the shutdown switches. When an engine shutdown switch is used to shut down the engine, the keyswitch must be turned to the OFF position for at least 15 seconds before restarting the engine.

Engine Speed/Timing

1. Crank the engine and observe the engine speed on the Cat ET status screen. If Cat ET indicates zero rpm, refer to Troubleshooting, "Engine Speed/Timing Sensor Circuit - Test".

   Note: Upon initial cranking, the status for engine speed may indicate that the engine speed signal is abnormal. This message will be replaced with an engine speed once the ECM is able to calculate a speed from the signal.

2. Ensure that the timing reference gear is installed correctly. The engine will not start if the gear was installed backward. Check for proper orientation between the crankshaft and camshaft drive gears. Correct the orientation and/or replace the drive gear, if necessary. Refer to Disassembly and Assembly, "Camshaft - Remove and Install".

Unit Injectors

Perform the "Injector Solenoid Test" on Cat ET in order to determine if all of the injector solenoids are being energized by the ECM. Refer to Troubleshooting, "Injector Solenoid Circuit - Test" for additional information.

Oil Level

Check the engine oil level. If necessary, add oil. Refer to Operation and Maintenance Manual, "Engine Oil Level - Check" for additional information.

Note: Engine oil supplies the injection actuation pressure circuit. Proper engine oil level is necessary for fuel injection.

Fuel Supply

1. Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. Prime the fuel system if any of the following procedures have been performed:
   • Replacement of the fuel filters

   • Service on the low pressure fuel supply circuit

   • Replacement of unit injectors

   Refer to Operation and Maintenance Manual, "Fuel System - Prime" for the correct procedure.

2. Check the fuel lines for the following problems: restrictions, collapsed lines and pinched lines. If problems are found with the fuel lines, repair the lines and/or replace the lines.

3. Check the fuel tank for foreign objects which may block the fuel supply.

4. 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.

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NOTICE
Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for two minutes before cranking the engine again.

5. Check the fuel pressure during engine cranking. Check the fuel pressure after the fuel filter. Refer to Systems Operation/Testing and Adjusting, "Fuel System" for the correct pressure values. If the fuel pressure is low, replace the fuel filters. If the fuel pressure is still low, check the following items: fuel transfer pump, fuel transfer pump coupling and fuel pressure regulating valve.

Combustion Problems

Check for combustion problems which can be caused by cold outside temperatures and mechanical problems.