Fuel tank vent?

[htwheelz67]

Last trip a couple weeks ago my genny would shut off after about 5 mins, carb is brand new so I noticed the fuel pump wasnt pumping properly,I checked all the lines looked ok so I ran into town and put on a new pump and same thing, so then I removed the fuel cap and BINGO solved the problem. The cap doesn't look like a vented one so where would the fuel tank vent be? Its a 2004 WW FS3000, its worked problem free for years with the same cap until that weekend.

[johntank]

My 05 KZ has a vent line/tube that runs up the side of the filler, just another place to check if you have not.

[fj12ryder]

My cap doesn't appear to be vented and I've wondered how the generator keeps running as the fuel level lowers. If I pump fuel out, when I remove the cap the tank hisses as the air pressure equalizes.

[Strabo]

My cap is not vented.

[Vulcanmars]

Sounds like you need a new cap. It should allow air in to avoid vacuum lock but not vent to keep the EPA happy. That's why we all get the big hiss when removing. It's possible to have a non-vented cap if the tank has a vent line somewhere. Usually near the tank up high on the frame.

[nayther]

I noticed mine does a great big his when I open the cap so assume its not vented but never had a problem, but I also know the cap doesn't seal 100% because when its full it sloshes out along the side of the trailer. I would think that it has to be a sealed system per EPA but I could be wrong, never checked.