Gas cap valve?

keggy

Cadet
Joined
Oct 26, 2009
Messages
14
Hey what is the valve for on my outboards gas tank. Its a 18 gallon tank on a center consol carolina skiff. The valve was open while the boat was sitting in the garage and I could smell gas so I closed it. Is that bad? Thanks!
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Gas cap valve?

A picture would help. But lacking one, and not knowing "where" the valve is or what it even looks like my guess would be it is the fuel tank vent. Closing it seals the tank. Just remember that it must be open when you run the engine. You cannot suck a liquid out of a sealed enclosure.
 

keggy

Cadet
Joined
Oct 26, 2009
Messages
14
Re: Gas cap valve?

The valve is right on the gas cap and its a very small little pressure relief valve looking thing. I kind of figured it has to be open when the boat is running and closed when not but wanted to double check. Thanks for the help.
 

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,392
Re: Gas cap valve?

Most likely a tank vent as stated already.
 

Home Cookin'

Fleet Admiral
Joined
May 26, 2009
Messages
9,715
Re: Gas cap valve?

Be careful closing it tight when the temps change and especially if it's sitting in the sun. Tank will swell up like a ballon.
Be careful leaving it loose when it might rain. Water will get in your gas.


Isn't everything in boating like that?
 

keggy

Cadet
Joined
Oct 26, 2009
Messages
14
Re: Gas cap valve?

Be careful closing it tight when the temps change and especially if it's sitting in the sun. Tank will swell up like a ballon.
Be careful leaving it loose when it might rain. Water will get in your gas.


Isn't everything in boating like that?

so do you leave it slightly open when storing in the garage?
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: Gas cap valve?

Leave it open just enough for the tank to breathe when the boat is sitting and has gas in the tank. But be wary of the elements and stowing the boat in a small enclosure with lots of gas in the tank.
 

Home Cookin'

Fleet Admiral
Joined
May 26, 2009
Messages
9,715
Re: Gas cap valve?

yes let it breathe; those fumes won't be dangerous (unless you are in a trunk of a car!)
I only tighten mine down when I am moving them otehrwise they stay open a little bit; more when I'm operating. When I am leaving it outside for a while I put a baggie over the cap, too, to keep out rain.
But here's the thing--don't keep gas around for more than 60 days. If you would be storing that long, empty the tank into your car.
 
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