G3516B Engines Caterpillar

Gas Fuel Flow Rate (Low)

Usage:

Probable Causes

High fuel temperature
Faulty gas pressure regulator or low fuel supply pressure
Obstructions in the fuel supply
Low Heat Value (LHV) of the fuel
Moisture condensation in the fuel

Measure the temperature of the fuel that is entering the fuel metering valve. Compare the measurement to the reading for the fuel temperature on the Caterpillar Electronic Technician (ET). Check Cat ET for a E223 High Gas Temperature.

If the temperature on Cat ET is different, determine the reason for the faulty signal from the fuel metering valve.

If the fuel temperature is high, determine the cause of the high fuel temperature. Check for proper operation of the equipment that treats the fuel prior to the engine.

If there is an active E223 High Gas Temperature, refer to Troubleshooting, "Gas Temperature (High)" for information that is related to troubleshooting the circuit.

Repair the circuit, if necessary.

Faulty Fuel Pressure Regulator or Low Fuel Supply Pressure

Measure the outlet pressure from the fuel pressure regulator. The fuel metering valve requires a minimum pressure of 10 kPa (1.5 psi) for the fuel supply.

If the pressure of the fuel supply is too low, adjust the fuel pressure regulator in order to achieve the correct pressure.

If the fuel pressure regulator cannot be adjusted to the correct setting, repair the regulator or replace the regulator.

Obstructions in the Fuel Supply

Check the fuel filter for restriction. Replace the fuel filter, if necessary.

Inspect the screen inside the inlet of the fuel metering valve for cleanliness. Clean the screen, if necessary.

Inspect the fuel supply lines to the fuel metering valve for obstructions. Clean the lines and make repairs, as needed.

Check the Gas Shutoff Valve (GSOV) for proper operation. Verify that the valve is fully open when the valve is energized. Verify that the GSOV does not stick in a partially open position. Repair the GSOV. Replace the GSOV, if necessary.

Low Heat Value (LHV) of the Fuel

If the fuel energy content is too low, the fuel metering valve could demand an excessive supply of fuel.

Check Cat ET for a E230 Fuel Energy Content Setting High. If the code is present, refer to Troubleshooting, "Fuel Energy Content".

Obtain an analysis of the gas in order to check the LHV and specific gravity of the fuel. Check that the value that is programmed into the Electronic Control Module (ECM) is accurate. Program the "Fuel Energy Content" parameter to the actual value of the LHV, if necessary.

Note: If the quality of the fuel is not consistent, obtain several analyses over a period of time. Program the "Fuel Energy Content" parameter to the average value of the LHV.