Best way to Vent storage tank?

[Xfaxman]

Duh!! I guess it does say it's vented. I must be getting old timers. It must take slot of pressure to vent. After being in the sun it almost blew cap outta my hand into the air.
Ummmm... Never mind.
Thanks for all the suggestions though.

I would guess it works like the fuel caps on vehicles, air can go in, but not out.

 

[Tractor Seabee]

My 50 Gal transfer tank came with a fill cap that has a spring loaded vent built into it. It maintains a positive pressure in the tank but opens to let air in when pumping fuel out. I never have had a condensation problem here in the wet Puget Sound region. No rust in the tank and no water build up. The positive pressure feature must work. Check this out:Cim-Tek Vapor Control Fill Caps (2" NPT) - Non-Locking Base and Cap - 60001

Ron

 

[hd6gtom]

Do it right buy the Prevent cap. A fuel tank should hold a little pressure inside. a small amount of pressure in a hot tank will seem like a lot.

 

[Garycw]

Do it right buy the Prevent cap. A fuel tank should hold a little pressure inside. a small amount of pressure in a hot tank will seem like a lot.

Apparently it came with vent cap. I didn't realize how much pressure it built up before venting. It works great. Each stroke is 1/2 gal.

Sent from the mountains