F225 TXRC bogging down - fuel rail pressure question

[TownsendsFJR1300]

Those screws simply rusted.. Obviously not SS

If you can find SS screws, same size, I'd install those instead of the rusty ones.

Also, just to confirm what's in the bottom of the VST, put a small magnet to it. If it's rust, the magnet will attract it....

.

[oldmako69]

Take a look at the pumps below.. While one example is for a Zuke, they make one for Yams. Just dig around a bit as my link has expired. The claim to fame for these pumps is the carbon brushes (?) inside as opposed to any metal. The water absorbed by and contained in the E10 eats away at the innards of the metal pumps and is likely what has corroded your screws.

This all ties into the guy I mentioned earlier who cut a used HP pump in half and discovered that it was rusting internally. His Racor and first stage filter were free from crud, yet the VST screen was full of it. I had a similar condition.

The HP pump, as I understand it delivers more flow to the fuel rails than the injectors squirt. The excess flow is shunted back to the VST where the little bits of crud from inside the HP pump then clog the VST HP screen. Some of the crud also winds up in the F filter, and some in the injector screens.

One of my HP pumps crapped out. I used this one.....

https://www.ebay.com/itm/29139369582...%3AMEBIDX%3AIT

I've only put about 75 hours on it, but so far so good.


Here are the carbon pumps, or as near as I can find of them...

https://www.ebay.com/p/Kemso-High-Pe....c100011.m1850

https://www.ebay.com/p/Fuel-Pump-for....c100011.m1850

[rodbolt17]

3.3, you can change all 6 injectors and clean the VST in 2 hours. the F1115 and 150 in 1.5.
its called maint .
do it now and again.
I am glad I never changed a fuel pump in my 87 3/4 ton chebby.
I just wish the only time it died was not right after I filled the tank.

[Crazy Train]

Success! Finally completed the remainder of the Spring re-commissioning work and launched her yesterday. Ran perfectly: instant start-up; smooth idle; no hesitation or bogging during acceleration at able to achieve and maintain WOT/high speed. Recapping, I: replaced all the gas in the boat fuel tank, changed Racor fuel filter and engine on-board fuel filter, had the fuel injectors cleaned, cleaned VST and VST filter, replaced spark plugs, and replaced the F filters. Of all of the items that I changed, I attribute my original issue (bogging down) to a mostly-clogged VST filter since it was the only item that clearly was degraded (clogged). I also believe that the majority of the material that clogged the VST filter is generated from within the VST or within the near-by fuel loop.

Thanks to this forum for all the help. Rockfish season opens this coming Saturday (Chesapeake Bay), and I'm back in the ****. Good luck!

[Crazy Train]

That should say 'back in the ****'. Also, before and after photos of the VST HP pump filter.