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Asked by: Renea Gulyak
automotive road side assistanceWhat causes air bubbles in fuel filter?
Last Updated: 28th February, 2020
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Simply so, should a fuel filter have air in it?
A fuel filter is going to have air in it unless you can bleed it. It starts out with air and then fills up. You can do a lot of parts changing or you can see if the problem is really what you think it is or something all together different.
Also, should a fuel filter stay full? When the filter is mounted on its' side the air has no where to go so the is full of fuel and the compressed air (at the same pressure as the fuel) that is above the fuel filter outlet. Mount it with the out let at the top and it should be full of fuel as the air has somewhere to go.
Consequently, how do you get air bubbles out of fuel lines?
How to Bleed a Gasoline Line
- Fill up the gas tank with fuel.
- Start the engine but do not allow air into the system. Have a friend turn the key in the ignition to “Start” for approximately 3 seconds.
- Allocate approximately 20 minutes for the engine to sit if flooding occurs while bleeding the fuel lines.
What are the symptoms of having air in the fuel line?
Air bubbles in a fuel line can lead to stalling, hiccuping or refusal to start. Keep your fuel lines free of air to help keep your car running smoothly.