3412E, C30 and C32 Marine Engines Caterpillar

Engine Cranks but Will Not Start

Usage:

Probable Causes

Diagnostic codes
Event codes
Fuel level
Oil level
Starting aids
Shutdown switch
Active Engine Shutdown
Electrical connectors
Circuit breakers
Flash file
Engine speed/timing
Injection actuation pressure
Unit injectors
Fuel supply
Combustion

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 logged codes. Troubleshoot any codes that are present before continuing with this procedure.

Fuel Level

Visually check the fuel level. Do not rely on the fuel gauge only. If necessary, add fuel.

Oil Level

Check the engine oil level. If necessary, add oil.

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

Remote Shutdown Switch

Make sure that the remote shutdown switch is run position. Use Cat ET to verify the status of the shutdown switch. If a problem with the remote shutdown switch is suspected, refer to Troubleshooting, "Switch Circuits - Test".

Electrical Connectors

Check for correct installation of the following connectors:

J1/P1 ECM connector
J2/P2 ECM connector
J20/P20 Engine speed/timing sensor connector
J44/P44 Engine speed/timing sensor connector
Unit injector connectors

Refer to Troubleshooting, "Electrical Connectors - Inspect".

Circuit Breakers

Check the circuit breakers. if a circuit breaker is tripped, reset the circuit breaker.

Flash File

Verify that the correct flash file is installed in the ECM.

Note: If a new ECM has been installed, the ECM will need to be programmed before the engine will run. Also, the ECM will not communicate with Cat ET if the ECM has not been programmed.

Engine Speed/Timing

Crank the engine and observe the engine speed on the status screen in Cat ET. If Cat ET indicates 0 rpm, refer to Troubleshooting, "Engine Speed/Timing Sensor Circuit - Test".

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".

Injection Actuation Pressure

Check the engine oil level. if necessary, add oil. Verify that the pressure for the lube oil system is accurate.
Note: Engine oil supplies the injection actuation pressure circuit. proper engine oil level is necessary for fuel injection.

Crank the engine while observing the injection actuation pressure on the Cat ET status screen. if the injection actuation pressure is at least 5000 ± 200 kPa (725 ± 29 psi), the problem is not in the injection actuation pressure control system.

Check the seals on the injection actuation pressure control valve. if the seals are faulty, replace the seals and repeat Step 1.

Check the wiring harness to the injection actuation pressure control valve for opens and/or shorts.

Measure the coil resistance on the injection actuation pressure control valve. If the coil resistance is not between 5.0 Ohms and 15.0 Ohms, replace the injection actuation pressure control valve.

If the injection actuation pressure during cranking is less than 5000 ± 200 kPa (725 ± 29 psi), the high pressure oil supply circuit may have a leak.

Unplug the injection actuation pressure control valve and the unit injector connectors.

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This engine uses high voltage to control the fuel injectors.
Disconnect electronic fuel injector enable circuit connector to prevent personal injury.

Do not come in contact with the fuel injector terminals while the engine is running.

Disable the unit injectors with Cat ET and/or the engine shutdown switch.

Remove the valve mechanism cover.

Crank the engine while checking the drain holes in the unit injector adapter and the jumper block seals for leaks.

Excessive leakage will result in a large stream of oil flow from the affected unit injector adapter drain hole(s), with easily visible splashing of engine oil off of the bottom of the jumper block adapter oil shield(s). IF an excessively leaking unit injector(s) is diagnosed, change only the excessively leaking unit injector(s). Leaking jumper block seals can also create this problem. This can be diagnosed with the technique that is described above. Replace leaking seals.

If the problem persists, there may be a problem with the pump compensator displacement control. Correct this problem with the compensator kit. Adjust the load for the spool spring by turning the retaining screw. Adjust the screw in order to obtain a pressure of 5000 ± 200 kPa (725 ± 29 psi) during engine cranking with the injection actuation pressure control valve unplugged.

If the injection actuation pressure remains low after installing a new compensator kit, install a longer compensator plug. The longer compensator plug that is marked with a "D" is part of the plug kit. If the injection actuation pressure is above the specified range, select the shorter compensator plug from the plug kit that is marked with a "B".

If the pressure cannot be obtained, replace the pump or rebuild the pump.

Unit Injectors

Perform the Injector Solenoid Test with 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 the proper procedure.

Fuel Supply

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.

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

Check for air in the low pressure fuel supply 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.

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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.

Purge air from the low pressure fuel supply circuit. Refer to Operation and Maintenance Manual, "Fuel System - Prime" for the correct procedure.

Check fuel quality. In temperatures below 0 °C (32 °F), check for solidified fuel (wax). Refer to Special Instruction, SEBD0717, "Diesel Fuels And Your Engine".

Check the fuel pressure after the fuel filter while the engine is being cranked. Refer to 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. Refer to Testing and Adjusting for more information.