if you first start the car, there will be a pocket of air, once the fuel has reached the carby, it shouldnt pick up air till the fuel runs low, or it gets too hot. check all the fuel lines, and nipples in the tank, some times if it has a primer on the tank, it will produce an air leak in the tank. a crack in the tank, or a bad fitted Nipple, will cause fuel to also leak, so if you find the tank area is a little wettish, then id replace the tank.
Serpent - Walter RC
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