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fuel starvation w/fuel cell in tii

Discussion in '114 type 1600, 2002, 2002ti/tii (1967-1976)' started by Fred Beck, Aug 2, 2008.

    Fred Beck guest

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    Recently installed an ATL 12 gallon fuel cell (SP-112) in my tii. Electric fuel pump (new Mesa Performance rebuild) is mounted behind cell at about mid-height of cell. When fuel level drops to about 7 gallons in cell the car starves after coming out of a sweeping right-hander (turn 10 at Summit Point). Power drops off and the A/F goes all the way lean. Then it recovers down the front straight and the car is fine for the rest of the lap. Filling the fuel cell to the top fixes the problem.

    I just took the cell apart and there are no obvious defects (duck feet positioned correctly, no holes in pickup hoses). Could it be that the electric fuel pump needs to be mounted lower than the cell? I measured and the pump is below the fuel level when the cell begins to starve. FYI, I am drawing fuel from the right side pickup, and using the left side pickup for the fuel return line. I put a tii metal filter on the suction side of the electric pump, but now see the fuel cell has screens on the pickups, so I don't really need it there. Tank is vented to atmosphere through a separate vent line. Any suggestions?

    Fred in MD
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    • Technical Service Advisor


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    Does the fuel cell have baffles? If not, all your fuel will slosh to the left side of the tank on turn 10. You can either put foam in or try making a cup for your pickup to sit in so that it does not slosh all the fuel away from the pickup.

    Fred Beck guest

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    The fuel cell baffling foam is in place, not missing any. I pulled it out yesterday when checking out the cell internals after talking with ATL's tech support. I just can't understand how it could suck air with 7 gallons of fuel still in the tank. I have considered an in-tank LP pump with baffled surge tank. ATL sells one (ATL-CFD-600-LP) that flows 23.5 GPH, which should be able to adequately feed the electric pump. However, I don't want to spend an additional $400 if there is really something else causing the problem. I am most interested to know if the location of the electric fuel pump could be of concern. Comments?

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