Gas coming out fuel fill cap

Stever00

Rinker 240 gas keeps coming out fuel fill. Boat is parked in barn. Gas tank was full. Ever so often gas comes out. Every time it does I pump out with hand pump into gas can. Over the summer I know I have pumped out over 5 gallon not to mention what went on the ground. I been thinking atmospheric pressure, temp changes . Yesterday it was only in the 60's and gas was coming out. This has me really worried about fire. 
From what I've read it may be fill house bent down whereas it needs to bend upward to fill hole. Also read it may be gas tank vent stopped up. Anyone familiar with this boat got any ideas what I need to do? How is vent system made on this boat which is a 97. I know regulations on how gas tanks are made have changed over the years. Such as anti flow back valves like Perko makes.

skennelly

Do you have a separate vent or is it a vented gas cap?  Sounds overfilled and atmospheric changes like you said are causing pressure to build.

Stever00

I been trying to figure it out this morning. This boat being a 97 has the tank vented up to the filler neck. I took the vent hose off at tank and blew air through it. I could hear it coming out filler neck vent. I've read that if this vent hose dips down and up it could cause problem. Funny if that was the case it would have always done it cause the hose is still routed and fastened to boat with original cushioned clamps. Like I said this is been doing this off an on all summer and fall. When I go out there and smell gas I pump some out. I know 3 or 4 times getting two or three gallon out. Seem like it would be low enough to be ok. Wish I knew the problem before the boat, building and my truck burn up.

GMSLITHO

Is there a rubber o ring on the gas cap 

Grahamu

What size is the tank? If you think it is still full after you taking 5 or 6 gallons, syphon off another 5 gallons. Can you turn on the key and see what the fuel gauge reads?

laureniac1

try adjusting the height of the trailer tongue jack- my 270 did this whenever it got hot the fuel expanded and came out vent - changed the angle of boat on trailer with the tongue jack worked for me 

Cableguy Greg

If you store with a full tank, the fuel expands when it gets warm out and pushes out the fuel filler. 

Pat310

Try lowering the bow. If too high the gas level might cover the vent outlet inside the tank. Then when temps warm up the change in pressure pushes gasoline out the vent instead of air. 

mattie

I would just siphon out more fuel till the problem stops.

Gasoline expands/contracts 1% for every 19*F.
If you have a full tank of 75 gallons. Can expand by 3/4 gallon & puke out.

Most people store full - I store our boat as close to empty as possible with non-ethanol & marine Sta-Bil. Never had an issue. 

Stever00

GMSLITHO said:

Is there a rubber o ring on the gas cap? 
  
Yes , and it needs a new one. Probably be hard to find one that size. Been looking.
I wouldn't have left so much gas in tank but by time I replaced fuel pump summer was over. I wonder if venting had something to do with fuel pump going out?

Pat310

@aero3113 posted this and they worked on my gas cap
https://rinkerboats.vanillacommunities.com/discussion/8532/friendly-reminder

Stever00

Thanks, that fuel cap looks same as mine. Even the rotten o'ring.