Originally Posted by bigmac
Automobile gas tanks aren't vented, boat gas tanks are as required by the USCG.
For my part, and to answer your question, NO, my fuel injected boat does not get any kind of rush of air when I remove the gas cap. If it did, I would be alarmed and start looking at the vent for a blockage.
Thanks guys for the responses.. Although it isn't what I wanted to hear.. I'm amazed my fuel pump could continue to pump against that amount of negative pressure, and am equally surprised at how completely sealed my the blockage in my vent must be.. I'll look into the situation more tomorrow. May be a mud-dobber's nest, but I'm amazed at how well sealed it must be..
Auto gas tanks are vented, in that they do allow air to come in to replace the fuel that is pumped out. But the vent is associated with the charcoal canister system that holds the vapors from the fuel and later introduces them into the intake of the engine to be burned..
I'm sure I can find the vent lines coming off the top of the tank in my 02 xstar.. but if anyone has any tips or suggestions for me I'd be eager to hear them.
Again thanks for the responses.