How to Prime a Fuel System

by Alexander Poirier
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Air often gets into the fuel line when a vehicle runs completely out of gas. This causes a vehicle to have problems starting, forcing you to "prime" the fuel system to remove the air. Pump fuel through the fuel line via the manual pump to prime a fuel system.

Step 1

Open the hood of the vehicle and locate the fuel pump; it is usually found between the fuel tank and the first fuel filter. Locate the manual primer on the pump. The manual primer can take the form of a lever or a plunger.

Step 2

Open the bleed plug on the fuel filter closest to the fuel tank. See the vehicle's owner's manual for the exact location of the bleed plug.

Step 3

Open the fuel supply valve to allow fuel to flow from the pump to the filter. The location of the valve will vary by make and model. Consult the owner's manual for specific locations.

Step 4

Prime the engine by either lifting and lowering the lever, or pumping the plunger; the specific action is dependent on the type of primer found on your engine.

Step 5

Continue to prime the engine until fuel escapes from the bleed-plug holes in a steady stream, without any air bubbles.

Step 6

Close the bleed plug and the fuel supply valve. Insert the key into the ignition and turn the engine over. If the engine does not turn, repeat the previous steps until it does.

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