- Industrial Engine:
- 3054C (S/N: 334562-UP)
- Engine:
- C4.4 (S/N: MMC1-UP; XYC1-UP; NCD1-UP; N4D1-UP; XYD1-UP; NCE1-UP; N4E1-UP; L1K1-UP; S1M1-UP; N4R1-UP; N4X1-UP)
- C4.4 (MECH) (S/N: 4461-UP)
There have been isolated issues with cylinder head gaskets that leak. This has caused an increase of pressure of the coolant system.
Install a new cylinder head gasket. Refer to Disassembly and Assembly, "Cylinder Head - Install".
If the original issue is the gasket for the cylinder head and no cause can be found with the cylinder head gasket, the cylinder head, fasteners and the cooling system package needs to be checked. If there is not an issue with the cylinder head, fasteners or the cooling system package, remove the fuel injection pump. Refer to Disassembly and Assembly, "Fuel Injection Pump - Remove".
The fuel injection pump must be taken to the nearestDelphi distributor in order to be checked to the test plan. A fuel injection pump that does not meet the specification of the test plan will cause issues with engine performance. If theDelphi distributor finds damage to the advance box of the fuel injection pump. This can lead to advanced injection timing of the fuel injection pump. This will result in high cylinder pressures due to the advanced timing of the fuel injection pump. This can lead to issues with the cylinder head gasket. This is indicated by the discharge of coolant from the expansion tank pressure cap.
Note: The advance box of the fuel injection pump can be damaged by trapped air.
Air that is present in the fuel can collect in the advance box of the fuel injection pump. If the hydraulic damping for the fuel is not effective the movement of the automatic advance piston is uncontrolled. This can damage the cover plate, the O-ring seal and the fasteners. Investigations have shown that this can lead to fuel leaks. In extreme cases, the advance piston travel can shear the cover screws.
Problems can occur within a few hours of the start of the engine, depending on the duty cycle and the amount of air in the fuel.
The reasons that the air is introduced into the fuel system are listed below:
- Running out of fuel and not priming the fuel injection pump correctly
- The low pressure fuel supply system is poor. It is possible to draw in air through joints or connections on the engine and the fuel lines when there is no sign of fuel leaks.
- Air can be drawn from suspension in the fuel if the fuel filter of the fuel transfer pump becomes congested. This causes a restriction.
- The fuel transfer pump may not be operating correctly or the fuel transfer pump draws in the air via damage to the sealing ring of the fuel filter bowl.
Ensure that the O-ring is seated correctly on the fuel filter bowl on the fuel transfer pump when the fuel filter element is replaced. Ensure that all supplied parts are installed correctly.
To check for air in fuel, refer to Systems Operation, Testing and Adjusting, "Air In Fuel - Test" for the correct procedure.
Note: Unless the cause of the air in fuel has been rectified, it is likely that any replacement fuel injection pump will have a problem in a short space of time. Ensure that the source of the air leak in the fuel system has been located and rectified. Ensure that the fuel system has been primed in order to ensure that there is no trapped air in the fuel system.
New Priming Procedure for the Fuel System
- Ensure that all low pressure fuel connections and high pressure fuel lines are installed correctly.
- Turn the ignition key to the RUN position. Leave the ignition key in the RUN position for three minutes. If a manual purging screw is installed, the purging screw should be slackened during priming the fuel system.
- Crank the engine with the throttle lever in the CLOSED position until the engine starts.
Note: If necessary, loosen the union nuts on the fuel injection lines at the connection with the fuel injector until fuel is evident. Stop cranking the engine. Tighten the union nuts to a torque of 30 N·m (22 lb ft).
- Start the engine and run the engine at idle for one minute.
- Cycle the throttle lever from the low idle position to the high idle position three times. The cycle time for the throttle lever is one second to six seconds for one complete cycle.
Note: In order to purge air from the fuel injection pump on Caterpillar engines with a fixed throttle, the engine should be run at full load for thirty seconds. The load should then be decreased until the engine is at high idle. This should be repeated three times. This will assist in removing trapped air from the fuel injection pump.
- Check for leaks in the fuel system.