D379, D398, D399 LOCOMOTIVE ENGINES Caterpillar

Fuel System Maintenance

Usage:

Fuel

See LUBRICATION AND MAINTENANCE CHART for fuel specifications.

Fuel Filter Elements

Checking Fuel Pressure Gauge

With engine running, the fuel pressure gauge should register in the NORMAL range. If the gauge registers in the OUT range, clean the primary fuel filter element, if so equipped, and/or service the fuel filter elements.

Cleaning Primary Filter Element

1. Stop the engine.

2. Close the diesel fuel supply line valve.

3. Loosen the nut on the cover and remove the case.

4. Remove the filter element. Clean the element and case in kerosene or diesel fuel.

5. Inspect and install the upper and lower cover gaskets. Install new gaskets if necessary.

6. Install the cleaned filter element and case.

7. Prime the fuel system.

Draining Water and Sediment

1. Close the fuel supply valve.

2. Remove the vent plugs located on top of the fuel filter housing.

3. Remove the fuel drain plugs. Drain water and sediment from the filter housing.

4. Install the drain plugs and vent plugs.

5. Prime the fuel system.

Installing New Fuel Filter Elements

1. Close the fuel supply line valve.

2. Remove the vent plug located on top of the fuel filter housing.

3. Remove the drain plugs and drain the fuel filter housing.

4. Remove the end covers.

5. Remove the filter elements.

6. Wipe sediment from inside the housing.

7. Close all drain valves.

8. Install new elements.

9. Inspect and install the cover gaskets. Install new gaskets if necessary.

10. Install the end covers.

11. Prime the fuel system.

Priming the Fuel System

1. Open the fuel supply line valve.

2. Move the governor control lever to the shutoff position.

3. Be sure the vent plug located on top of the fuel filter housing is open.

4. Operate the priming pump lever until no air bubbles are visible through the glass window.

5. Close the vent valve.

6. Start the engine.

Bleeding the Fuel System

If the engine runs rough, release trapped air from the fuel lines.

With the engine running:

1. Loosen a fuel line-loosen either the line nut at the fuel injection pump, or the line nut at the nozzle.

2. Allow the fuel to spurt until the fuel stream is free of air bubbles.

3. Tighten the line nut. Proceed to the next fuel line and repeat the procedure.

4. Continue this procedure for all fuel lines.

Woodward PGEV Governor

Checking Governor Oil Level

With engine running:

1. Check the governor oil level sight gauge.

2. Maintain the oil level BETWEEN the ADD and FULL marks. Slowly add oil as required. See the LUBRICATION AND MAINTENANCE CHART for proper oil to use.

Show/hide table

NOTICE

Do not fill above the FULL mark. Overfilling causes aeration of the oil, which causes surging of the engine.

A hunting, or surging, condition will exist if the oil level is either above the FULL mark or below the ADD mark while running.

Changing Governor Oil

1. Move the governor control lever to the shutoff position.

2. Drain the hydraulic servo mechanism and the governor case by opening the two drain cocks.

SERVO DRAIN

GOVERNOR CASE DRAIN

3. Close both drain cocks.

4. Fill the governor to the FULL mark on the sight gauge with clean oil. See the LUBRICATION AND MAINTENANCE CHART for proper oil to use.

Bleeding the Governor

1. Loosen each air vent plug until oil begins to leak passed the threads.

AIR VENT PLUG

2. Start the engine.

3. Open the compensating needle valve several turns. This should cause the engine speed to surge.

OPENING COMPENSATING NEEDLE VALVE

The surging causes movement of all governor parts, and forces the trapped air through the governor oil passages and out the vent plugs.

4. Allow the surging to continue at idle speed.

5. When a solid stream of oil appears at each vent plug, tighten the vent plugs.

6. Add oil to the governor if needed.

7. Close the compensating needle valve slowly until the surging condition is eliminated or minimized.

8. Allow the engine to idle until both engine and governor reach normal operating temperature.

9. Open the compensating needle valve several turns and allow the engine to surge.

10. Slowly close the compensating needle valve until surging is completely eliminated. This should occur when the needle valve is opened between one-quarter turn and three full turns.

11. Test the governor stability by disturbing the engine speed. If the engine speed surges, close the needle valve slightly and test again.

Changes to the final setting will only be necessary when a change in the ambient temperature is sufficient to affect the oil viscosity.