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Unable to fill tank

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  • Unable to fill tank

    I have a 2001 F-150 BiFuel truck.
    Usually when I hook up at the CNG station I can hear the tank pressure equalize, then the pump starts filling the tank. Since we hit 105 degrees in Seattle last month, I am unable to fill the tank.

    I connect up the hose, lift the lever on the pump, there is no sound of pressure, just a dull thud, and the pump stops.

    I suspect a faulty solenoid on the fill line, but don't know enough about the systems to determine if this is the cause.

    Any tips on diagnosing this would be great, since I have run out on CNG, and am having to burn that damn gasoline now.

    Kenmore, Wa
    Last edited by KronoNaut; 09-24-2009, 02:46 AM.

  • #2
    Re: Unable to fill tank

    The tank solenoid acts as a check valve when filling, it allows gas into the tank, activated or not.
    Check your fill recepticle to see if you blew out the o-ring. When you look at your fill recepticle, there should be a black o-ring just inside the hole in the center that seals to the station's fill nozzle. If the nozzle can't seal and push back the center nipple inside of the nozzle, gas can't pass to your recepticle. This is a common problem, usually caused by turning the nozzle while it's locked on to the recepticle.
    I get replacement o-rings at Ace Hardware, but I'm sure a dealer would be glad to charge you an arm and a leg for one. Check your owners manual, if you have one. I've seen them left or attached inside before.

    Hope this helps.
    Your Friendly Nazi Squirrel Administrator