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Fuel pumps

Ricksrinker

New member
I seem to be having a fuel "delivery" problem-
2006 MPI 350/5.0, bravo lll.
Short recap, boat seldom used over 3 years and started to get it back to the water. 320 hours.

Pumped out and desposed of 75 gallons of fuel. Water and some crap in the fuel and that was pumping out through the fuel rail when I took a sample.
Ended up replacing the starter trying to crank- it was at its end. New starter in, two bolts, two hot wires and one small post that goes to the alternator I believe.
As the starter was dying it sounded like it wanted to start but stumbling.
New starter cranking but getting no firing.
I thought I only had one fuel pump but turns out I have the cool fuel- I know it's common, just never had that problem.
I dropped the fuel water separator and it was dry. I suspect the engine was trying to start on the fuel that was left in it, so the high pressure pump in the cool fuel on the port side of the motor would be working? I pulled the regular fuel filter to make sure no restrictions going back. That low pressure pump is like 600 bucks. The high pressure one I did order- it was 45 bucks which is pretty much a std gm pump.

So how does this system work?

When t turn the key I get the wirr..that must be the high pressure pump trying to load up the fuel rail?

What energizes the low pressure pump? It just pumps into the fuel water separator to be sucked out of there by the high pressure pump? How do I test the plug for power? What triggers that pump to pump fuel?

Fuses- on the top of the motor by that push button master selonoid, there is a flat fuse bar with 3 yellow/10 Amp fuses that at least one I'm told is fuel pump related. They are all fine. There are two other relays I have no clue what they are or how to check them.

While it might be a coincidence I can't help lean to something electrical...when the starter gave up the ghost it made a terrible electrical short kind of sound...like an electric chair in a horror movie...but nothing tripped that I can find..I don't recall undoing any other wires to get the starter out but the timing is off

I don't know if buying a manual would do me any good? It would have to be pretty basic to be of use. If I got a mobile vessel view, would that possibly give me a code? I know it won't for fuel or fuel pressures but if something else was zapped?

Sure looking for some ideas!
 
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