I just installed a Walbro fuel pump in my 91 civic (pain in the ***). Car started fine with no leaks. Then I went to the gas station to fill up. Put in a full tank and noticed major leakage from what seems to be the top part of the tank. After using a couple gallons of gas driving, the leakage problem seems to have subsided.

Is it possible that there is a leak where the filler neck goes into the tank? Are you supposed to disconnect the filler neck at the gas cap when you drop the tank?

 

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