Help me~ Gas leaking out of cap

[Supersportster]

Hey all, so I have some bad luck... I sealed around my transom with silcone and am ready for the boatin season,

Today I smell gas, and I go out there and its pushin up out of the screwed in tight gas cap...

the boat is 89 sylvan 18 foot aluminun with an under the floor tank...the tank was full, but not right up to the top, and it was fine all winter..

It has been real hot lately but what would cause this? is there a vent on the tank i can check somewhere?

worst part gas was jsut sittin on my new silicone...

thanks for any help...

 

[cpubud]

Re: Help me~ Gas leaking out of cap

should be a vent somewhere,silicone is the last thing you want to use on a boat to seal anything.

 

[Supersportster]

Re: Help me~ Gas leaking out of cap

LOL I know I know... It was that 5200 3m I keep readin about on here..

Should have been more clean, but in my frustration I used teh term silcone..

I syphoned some gas out... Could it be that my dumb***** filled it way to full in the fall, now in the first heat, it had no where to expand to?

 

[cpubud]

Re: Help me~ Gas leaking out of cap

could be but it still should still not come out the cap it should be pushed out the vent tube.

 

[DuckHunterJon]

Re: Help me~ Gas leaking out of cap

The tank has to be vented somehow, somewhere. When running, you are pulling gas out of the tank. If it isn't vented, it will pull a vacuum in the tank to the point where the fuel pump can't pull any more gas out.

Portable tanks have a vent that the user can open and close for transportation. A fixed tank should have a permanent vent. Sounds like yours is plugged. Get in the the bilge and look for two hoses on the tank. One will be the filler, the other is the vent. Check for blockages.

 

[nlain]

Re: Help me~ Gas leaking out of cap

My tank is vented back to the fill neck right at the cap, if too full gas will push out the cap, if tank filled last in cool weather it will expand enough to push out the cap. The vent may be a one way vent, let air in not out.

 

[Supersportster]

Re: Help me~ Gas leaking out of cap

It was filled in cold weather..I think its good now, I drained some gas out...

It got dark last night, I was trying to see where the vetn was to make sure its not blocked. I will have a look again today, and take a couple pictures of the fill tube, and the primer bulb hose and down at the back through the bilge..

Thanks for the help guys. Just a kick in the head to see gas pushing out all over my newly sealed transom...

Do you think that gas hurt it? I hosed it all off and it wasnt leaking...But the gas could have been eating away at it for a few days before I noticed...