3512B Marine Auxiliary Engine Caterpillar

• Electrical power supply

• Low fuel level

• Starting aids

• Shutdown switch

• Active engine shutdown

• Electrical connectors

• Circuit breakers

• Personality Module

• Engine Speed/Timing sensor

• Injector solenoid

• Fuel supply

Perform the following tests in order:

1. Perform the diagnostic functional test Troubleshooting, "Electrical Power Supply".

2. Visually check fuel level. If necessary, add fuel.

3. If cold ambient conditions exist, check operation of starting aids. Ensure the proper operation of the Jacket Water Heater. Repair the Jacket Water Heater and/or replace the Jacket Water Heater. Check for presence of solidified fuel (wax).

4. The shutdown switch should be in the OFF position. Connect the Caterpillar Electronic Technician Cat (ET). Use the Cat ET in order to verify the status of the shutdown switch. If the Cat ET will not communicate with the Electronic Control Module (ECM), perform the diagnostic procedure Troubleshooting, "Electronic Service Tool Will Not Communicate With ECM". When a shutdown occurs, the Engine Control Switch (ECS) must be turned to the OFF/RESET position. The ECS must then be turned to the DGCP/START/ENABLE position before the engine will start. Perform the diagnostic functional test Troubleshooting, "Emergency Stop Switch".

5. Use the Cat ET to determine if any active shutdowns are present. If a Shutdown is Active, determine the reason. After you correct the problem, turn the ECS to the OFF/RESET position for at least 15 seconds before you try to restart the engine.

6. Check for correct installation of the ECM connectors J1/P1, J2/P2, Engine Speed/Timing Sensor J20/P20, Secondary Engine Speed/Timing Sensor J44/P44 and Unit Injector connectors J4/P4 through J15/P15. Perform the diagnostic functional test Troubleshooting, "Inspecting Electrical Connectors".

7. The circuit breakers may exceed the trip point due to overheating. Check the circuit breakers on the engine instrument panel. Reset the circuit breakers if the circuit breakers are tripped.

8. The diagnostic code 253-02 should not be present. If the diagnostic code is present, perform the diagnostic procedure Troubleshooting, "Programming Parameters".

9. Crank the engine and observe the engine speed on the status screen of the Cat ET. If the Cat ET indicates 0 rpm, perform the diagnostic functional test troubleshooting, "Engine Speed/Timing Sensor".

   1. 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. Refer to Disassembly and Assembly Manual.

10. Perform the Injector Solenoid Test. Verify that the ECM is energizing all the injector solenoids. Perform the diagnostic functional test Troubleshooting, "Injector Solenoids".

11. Check the fuel system, if there is no smoke at the exhaust. Check fuel lines for the following problems: restrictions, collapse and pinched line. Repair the lines and/or replace the lines. Refer to Systems Operation, "Fuel System".

    1. Check the fuel tank for foreign objects which may block the fuel supply. Check for air in the low pressure fuel supply system after you perform the following procedures:
       • Replacing the fuel filters

       • Working on the low pressure fuel supply circuit

       • Replacing unit injectors

    2. Purge air from the low pressure fuel supply circuit with the hand priming pump and by cranking the engine in 30 second cycles. After you crank the engine, stop for two minutes. This will allow the starting motor to cool. Loosen the vent plug for the fuel return line. The plug is located on the rear upper left side of the engine block. Hand prime the engine again if air in fuel continues. A sight glass in the low pressure supply line is helpful in diagnosing air in the fuel.

    3. 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 while the engine is cranking. Check the fuel pressure at the filter. Refer to Testing and Adjusting, "Fuel Pressure"for correct pressure values. If pressure is low, check for plugged 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. Check for a problem with the combustion system.