Fuel Tank Unit: Description and Operation

Fuel System:

FUEL SENDER
The fuel sender has a float, wire float arm, and a rheostat. Fuel level is sensed by the position of the float and float arm which operate the 90 ohm rheostat. As the float position changes, the amount of current passing through the rheostat varies, thus changing the gage reading on the instrument panel.

FUEL STRAINER
A woven plastic strainer is located on the lower end of the fuel sender pickup tube in the fuel tank. This strainer prevents dirt and water from entering into the fuel line unless it becomes completely submerged in water.

Diesel engine vehicles have a check valve that will permit fuel to pass if the strainer becomes plugged with paraffin during cold weather operation.

When this plugging occurs, the last four gallons of fuel will not be used due to the location of the check valve. Therefore, it is important to keep the fuel tank above the 1/4 mark at temperatures below 6°C (-20°F) when using number two diesel fuel.