2015 F115 VST running dry

[wheelin23]

Hello all,

As the lakes start to thaw here in MN I have begun getting the boat ready.

At the end of last season I would have the engine die out on me while cruising around mainly at high speed. The engine then wouldn't start as if it was out of gas. I would go to pump the bulb and it was hard but still no start. Would I found out would get gas back into the system was to open the bleeder on the bottom of the VST and then the bulb would loosen up and and the VST would fill up. Seemed like it was locked up with vapor. I replaced all the filters as and even the low pressure pump and confirmed it does indeed pump fuel from the tank but the problem still happens. The VST essentially is running dry and not refilling then locking up with what I assume is vapor under pressure. I have taken it apart multiple times and cleaned every inch of the thing, replaced the float and needle but it will still happen and the only way to get primed back into it is to open the bleeder and pump the bulb until it fills and gas comes out of the tube. I confirmed that water is running through it properly for cooling and can't think of anything else I could check that's obvious. I don't get any trouble codes pointing to anything either.

Thoughts?

[DennisG01]

Strange. When you opened the bleed screw, did you hear a hissing sound? And then... could you feel air escaping (VST under pressure) or was being sucked in (VST under vacuum). Probably was hard to tell.

Normally, I would first look at a fuel supply issue - and with your systems, a clogged vent line. However a clogged vent line will often show a fuel bulb as collapsed.

When the issue happened... and before you opened the bleed screw... could "feel" fuel trying to be pumped when you squeezed the bulb?