VST Tank question

[Tatt00z]

Good afternoon friends, when I parked my boat last year 2003 HPDI 250 motors were running flawlessly. When I launched my boat this year, both motors ran fine for 20 minutes or so , then the port motor cut out, like it ran out of gas. Primed it a few minutes, it started back up and ran for a few minutes, the cut out again. I managed to get it in the slip, then came back down to marina a few days later. Idled the motors, and they both idled at 2200 rpm for 30 minutes or so. Went out Saturday , both ran fine for 20 minutes, then the port motor cut out again, but this time wouldn't start again. Went down today and checked the gas in the VST tank, I can hear the high pressure pump run, and pressurized gas came out of schrader valve. Checked pressure, but my adapter failed, so I'm waiting on that part now, so I can get the accurate reading. When I drained the VST Tank, probably only about 4 ounces of gas came out. So I'm guessing the float maybe be stuck, not letting anymore gas get to the VST Tank. Is there any other things I should check? I'm getting spark, plugs are brand new, and I replaced both low pressure pumps last year.
Thanks in advance, Glen

 

[Sparkdog118]

Is your primer ball locking up like a restriction in the tank feed or a collapsed supply hose? When you pump the ball, does it stay collapsed or not spring back into shape quickly?

 

[Sparkdog118]

Also check the fuel filter in the boat for a pinhole that may be sucking air.

 

[Tatt00z]

I forgot to mention that it had an electric primer, the fuel bowl with the filter is full, I need that Schrader valve adapter piece to come in, so I can get a better idea.
Thanks Sparkdog for the suggestions.

 

[seasick]

Simple things first: Check the on motor fuel filter especially for an air leak. Normally the bowl should be about 3/4 full. If empty, it isn't getting gas due to some sort of problem upstream ( towards the tank). If it is full at idle, it probably is leaking air. What maintenance did you do prior to this event? Were filters replaced?
4 ounces sounds like too little for the capacity of the tank. If that is true, than there is a fuel supply issue but first, pump the primer bulb until it is quite firm. Assuming it does get firm, now drain the VST and see how much gas is in it. You can drain the other motor's VST also to get a reference.
Note that after draining the VST, it should be filled up manually with the primer bulb before power it turned on. The pump does not like to be run dry.