Fuel Leaking Issue?

[MtnMan210]

I had a weird issue show its head today. I had the boat (1999 21i) out for the 4th. We were on Crowley Lake at roughly 7000ft. Had a great trip no issues at all. Spent all day on the water the last day. By my guess I should have used between 12-18 gallons of gas. Got back home Tuesday night (Thousand Oaks roughly sea level) and had some fuel left in the fuel cell used to store fuel. So after backing into the driveway figured I'd fill the boat. I put in 6 gallons and gas went everywhere. My first clue something was wrong. I couldn't imagine I'd be that far off on my fuel consumption calculation. I figured there was some air bubble somewhere, from the altitude change and it might settle so I shut the cap and went inside, no issues. Today (Thursday) sitting in the house I get a strong gas smell coming from the driveway and go to find gas pouring out of sealed gas cap! Open the cap and gas goes everywhere. Any ideas on where to start on this one??

Also any tips on getting the yellow streaks off that it left down the side of the WHITE gel coat

[Ruger761]

Sounds like your tank vent line is clogged and not allowing the tank to vent building pressure and blowing gas out. Id start by taking the line loose from the tank and blowing it out.

a good cleaner wax will remove the yellow streaks.

[MtnMan210]

I'll give that a shot tonight. And see if I helps. I was also thinking the way it sits in the driveway might be affecting it. It sits bow low, I was going to pull it out on the street and level it out and see if that helps.

[Tulsah]

if your boat is backed into the driveway and sitting bow low, then that is the problem. The fuel tanks don't vent from the rear, they are internally plumbed to vent from the front. Even a relatively low fuel level in the tank is enough to submerge the vent line when it sits with the bow low in the driveway. Add a bit of heat from the sun or sitting under the tarp, and the expanding fuel pushes out through the line. I suffered through this for a couple of seasons until I took everything apart and figured out the issue. My solution is to simply leave the gas cap cracked just enough such that pressure can't build in the tank. With the cover over it, there's no chance of getting any water into the tank.

[MtnMan210]

Thanks for the info. I was thinking it might have had something to do with how it was sitting. I never have filled it in the driveway before but never have had an issue filling elsewhere. So that was the new [a

[MtnMan210]

Quick update problem solved.

Pulled the boat out level in the street and opened the cap. Filled another 7 gallons without issue and backed it back in the driveway. No fuel spillage issues or pressure issues. Looks like the vent along with the bow being low was the problem. Thanks for the input.

[Ruger761]

Good deal.

[Tulsah]

If it's sitting bow low for any period of time, I suspect that it will purge gas again at some point. BTW, this isn't a failure of the air/fuel separator in the vent line ... with the internal vent tube under the level of gas in the tank, the pressure can and will build to the point where it overcomes the separator's capability, and out comes the gas.