Gas leaking from vent

[rmhaack]

So I could smell gas in my garage tonight. Upon inspection I realized gas is leaking out of the back of the boat from this "vent" looking deal. It is pictured below as a close up and it is in the center of the larger picture. It is a round "vent" or something located on the back of the boat. It almost appears to be an ignition switch (like you could insert a key) which it obviously isnt and the slot isnt open. (That is just the closest thing I could relate it to. I filled the boat up to the top with gas before winter as part of the winterizing process. The tongue of the trailer was sitting up on a cinder block so it was up higher then normal. But I havent moved it all winter and it just started leaking fuel out of this. What is it and why is it all of a sudden now leaking? Thanks.

 

[Jeep Man]

Re: Fuel Leak

Re: Fuel Leak

I don't know where you are so I can only guess that a bit of heat has caused expansion, or, if it's a plastic tank, a bit of tank compression could result in rise of fuel level.

 

[Bearfan]

Re: Fuel Leak

Re: Fuel Leak

I don't know where you are so I can only guess that a bit of heat has caused expansion, or, if it's a plastic tank, a bit of tank compression could result in rise of fuel level.

I was guessing winter and compression.

 

[CaptainSkip]

Re: Fuel Leak

Re: Fuel Leak

Sounds like the same vent, fill tube problem here...
http://forums.iboats.com/showthread.php?t=367947

 

[Woodnaut]

Re: Fuel Leak

Re: Fuel Leak

I filled the boat up to the top with gas before winter as part of the winterizing process. The tongue of the trailer was sitting up on a cinder block so it was up higher then normal.

1) It's possible that the tank vent enters the top of the fuel tank closer to the back of the tank than the front. If the tank is very full, and if the boat is tilted up at the bow, then the gasoline might be covering up the vent opening in the back (and top) of the fuel tank.

2) The tank is probably not completely full - there's probably a small amount of air tapped in the forward (higher) end of the tank. During very cold temperatures this small amount of air contracted which would have drawn in a litlle more air from the outside world through the tank vent. It entered the tank and bubbled through the gasoline to the air pocket.

3) Temperatures warm up, the air expands a little and pushed some gas out the vent line.

So the theory goes. I always make it a point to store my boat with the bow up high so as to keep the bilges dry. Since yours is in the garage, however, there probably isn't any way to get water into the bilges during storage. You might consider lowering the bow and putting it on an even keel. This might eliminate the problem.

 

[rmhaack]

Please Delete Post

Please Delete Post

I had a suspicion it was related to this, but I wanted to confirm it...Thanks.

 

[Gary H NC]

Re: Please Delete Post

Re: Please Delete Post

Lower the bow if its inside the garage.
The fuel tanks do expand and contract with changing temps.

Great example Woodnaut!