Yamaha F150 mystery substance in VST tank

[Surfjones3]

My VST was done in the spring before putting the boat in the water, everything was going well for a few trips then the boat began running rough-sputtering stalling out then finally got to the point where it was cranking but not starting. I found that there was no pressure on the fuel rail at key on and by process of elimination figured the high pressure pump in the VST was dead. When I got into the tank again I found the gas had this black gummy substance in it. Not wanting to destroy another $400 pump I checked every point from the tank to the VST and found the gas was spotless. I can’t figure out where this came from and am not really sure how to proceed bc I’m worried this might happen again. Has anyone ever seen this before, If the pump was possibly run dry could it be from the pump? Any advice on how to proceed.

[rejesterd]

It looks like one of your fuel lines is rotting on the inside.. that’s probably what those black bits are. Replace the lines going from the tank to the engine. You should also replace the fuel filter, since it probably has the same gunk in it.

[Surfjones3]

I thought that as well but I checked all my filters before the VST and they were clean, I also checked the gas right at the low pressure pump and it was also clean. I was expecting to find the same thing in one of the filters but the two before the vst are spotless so how could it be in the VST. 251E94C0-1B8A-48E2-BEFF-802EAB7AA9B5.jpeg

[99yam40]

fuel flows thru the electric motor to cool and lube it,
maybe it is from the motor itself as it failed.
but the no flow is probably what took out the pump

[Surfjones3]

I feel like I’m traped in between a rock and a hard place. Would you replace the pump and filter and wrap it up or look for another area where this came from. Some have suggested replacing all the fuel lines, but if the gas is clean in the fuel water separater than how could the stuff made it past 3 filters to just the VST

[99yam40]

has the pump failed for sure?
if so I would look at any rubber between the filter and VST.
replace the pump and screen ,run it for some time and then recheck to see if anything is getting onto the screen
did you cut the filters to inspect what they caught?

[Surfjones3]

I couldn’t get the pump to run with test leads hooked to my battery, the filter isn’t contained by a cover so you can see a little in the first picture it just has that black crap gummed up on it. The problem is on the F150XA the VST is a pain in the ass to get to so to recheck consistently is difficult .

better picture of the vst filter, the filter is only3-4 months old
04FCF014-1BA5-42CD-92F3-4432E950E587.jpeg

[99yam40]

what kind of tank do you have in the boat?
and what kind of fuel do you run ?
I bet the injector screens look bad too

[Surfjones3]

It’s a 2014 parker se I believe it’s an aluminum gas tank. To back track a little in the story, I had put reconditioned fuel injectors in the beginning of the season, when I started having issues I thought possibly the refurbished injectors were bad so I decided to send the originals ones to be cleaned and then put them back in the engine, the report I got on them was that they were perfect, so I put the original ones in again, have no more then a few hours on them before the pump went south

[Surfjones3]

I’ve always put 93 well treated with Yamaha stabilizer and ring free

[99yam40]

non ethanol?

[Surfjones3]

No it’s e10 can’t get ethanol free on Long Island unfortunately

[Surfjones3]

I’ve went through the VST with a fine tooth comb and blew out every line with cleaner to see if anything similar came out and everything was clear, the only thing I found was the bottom of the float had a linear mark on it like it was scrapped with something sharp. I don’t think it makes sense that all the crap that was in there came from that but I can’t for the life of me figure out what else it could be 04B78960-1CAF-4C7C-9F4A-C208DF6079A6.jpeg

[99yam40]

I have read about carbon brush dust from the motor, but what you found does not sound like that.

when you replaced that filter/screen 3-4 months ago, did it have something like that the old one?

[Surfjones3]

No it was much cleaner