What’s the one way valve look like? New to the jetski world is it the little fuel filter looking thing right on top the gas tank?
Edit: short version, what BK said. Longer explanation below if you’re interested.
Yes.
the volume of fuel decreases as your motor runs. This would create a vacuum in your tank if air were not allowed in. The negative pressure would starve your motor of fuel. The one way is suppose to let air into the tank to prevent negative pressure.
it’s mainly suppose to prevent fuel from getting out though. Otherwise fumes in the hull or it would pour out when inverting. When they fail, it’s like having no valve at all, so fuel exits at various rates.
It’s okay that they don’t let air out. Having pressure in your tank is okay. Your carbs have a return line that puts and excess fuel back into the tank. A tank with a properly working one way valve would vent pressure when you take off the gas cap after the ski has been sitting on the sun. If it doesn’t hold pressure, then it’s letting it escape into your hull.
side bar, same topic, if your tank builds up too much pressure, it can pop off the valves in your carbs. The fuel will feed into your cylinders, and if bad enough, into your exhaust. In really bad situations it’s not only a potential fire hazard, but it could also hydrolock your motor and you unknowingly bend a rod or blow out a bearing cranking it over. It’s best to always store the ski with your fuel selector in the off position to avoid this.
