Fuel System Problem

[Scotty318]

1994 318ic 217k miles. If I fill the tank more than 3/4 full I get massive fuel vapors. Once the fuel level drops by a few gallons the vapors go away. I have changed the vapor canister in the engine compartment. It made no difference. Any other suggestions?  I saw the thread on the filler neck and o-ring issues.  I'll check those. If I need to change out the tank, is that a DIY project for the average dude?  Thanks for this forum!

[a930rocket]

Pull up the back seat bottom when you fill up next and see if the gas flows out the pump connections. It also might be the vent or filler neck leaking.

[B318M42W]

+1 pulling the seat and checking where it leaks!   top of the tank air return/overflow when fulling pipe. most likely at the junction of the tank and pipe ( largest one, right hand side, about 1'' in diameter)