While replacing my fuel filter today, I noticed a rubber hose running right behind the filter that was broken off. It looks to me like a vacuum line and it used to be attached some sort of valve.

Does anyone know what this is?

I've included a photo of the part the hose used to be attached to.

 

looks like the roll over valve, I am not sure were the hose goes on the eng. is part of the old hose still hanging around under the frame?

 

Yeah, the old hose was still there. The original hose actually looked pretty good, but there was a rubber piece connecting the hose to teh valve. I replaced it with a piece of fuel line for now.

What's a roll over valve?