C9 Marine Engines Caterpillar

Probable Causes

• Diagnostic codes

• Event Codes

• Electronic Control Module (ECM) power supply

• Oil level

• Starting aids

• Remote shutdown switch

• Starting motor solenoid or starting circuit

• Engine speed/timing

• Unit injectors

• 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.

ECM power supply

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

Oil Level

Check the engine oil level. If necessary, add oil. Refer to Operation and Maintenance Manual for additional information.

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

Starting Aids

Air Inlet Heater (if equipped)

Make sure that the air inlet heater is operating correctly. For additional information on the air inlet heater, refer to Troubleshooting, "Air Inlet Heater Circuit - Test".

Oil Grade Plug

Make sure that the correct oil grade plug is installed. For additional information, refer to Operation and Maintenance Manual.

Remote Shutdown Switch

Access the status screen on Cat ET that displays the remote shutdown switch status. The remote shutdown switch status on Cat ET is called "User Shutdown".

If the voltage is not in the proper range, refer to Troubleshooting, "Switch Circuits - Test".

Starting Motor Solenoid or Starting Circuit

Remove the starter and visually inspect the pinion of the starter and the flywheel ring gear for damage.

Test the operation of the starting motor solenoid. Check the condition of the engine wiring for the starting motor solenoid. Test the operation of the starting motor. Refer to Systems Operation/Testing and Adjusting.

If necessary, repair the starter or the starter circuit.

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. 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.

Unit Injectors

Perform the "Injector Solenoid Test" on the electronic service tool 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.

Fuel Supply

1. Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel. If the engine has been run out of fuel, it will be necessary to prime the fuel system. Refer to Operation and Maintenance Manual 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. 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

   Note: A sight glass in the low pressure supply line is helpful in diagnosing air in the fuel. Refer to Testing and Adjusting for more information.

5. Check the fuel filters.

6. 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.

7. Check the fuel pressure during engine cranking. Check the fuel pressure after the fuel filter. Refer to Systems Operation/Testing and Adjusting 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.

Examples of combustion problems are shown in the following list:

• Outside temperatures are too cold.

• Mechanical problem