After much testing I could not figure out what the problem was. I ended up taking it to my engine builder in Michigan to get some help. When I got there to my surprise there was another well know engine builder there as well. So I had two of the very best trying to figure it out. They were stumped a bit too. We changed the fuel pump, no change, new pressure regulator no change, it wasn't until we changed all the fuel lines and fittings that it fired up. They thought the braided return line was the issue. Said they had seen the braided lines cause problems before. I never saw any fuel leaks, but could smell fumes, not knowing why or where it was coming from. Not that I didn't try.

Whenever I checked or changed my sea pump impeller I have to remove the water separator and move it to the side to get access. That return fuel line would kink when I did that. After many years it kind of had a set spot that it would bend at. That could have been where the leak was coming from, I don't know.

It was one of those issues that was hard to detect. For whatever reason it is fixed now .

Sometimes fuel lines will collapse from within and look ok on the outside, the Merc.cool fuel line are easy to pinch and usually wont straighten out completly,,,glad its fixed

[QUOTE=Revd Up;4706456]That is what we thought was happening. Fuel pressure was spiking and pegging the pressure gauge when I cranked it.


My engine builder was thinking the fuel pressure regulator was suspect and the computer (MEFI 3) was shutting down the injectors when it saw too much fuel. First he wanted me to check the return line for obstructions and change the separator . My return goes back to the separator not the tank.

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The ECM does not monitor fuel pressure period.It has no idea of any too little or too much fuel delivery. The ECM commands the injectors pulse width for rpm / load and other factors for a very short jist.


The statement MEFI 3 was shutting down the injectors when it saw too much fuel --- SAY WHAT -- I would love to hear that conclusion from the engine builder. I believe I know who that is. That is bogus

John,

That wasn't a direct quote from the builder, just my interpretation of our conversation.

Not wanting to post any names or make this into a pissing match, I will just leave it at that.

I understand totally. Was making a post about it only.

Will ADD thou.

Follow up - just thinking off the top of my head for this --- if you have a pressure monitoring sensor installed for fuel psi that is directly adapted to a discrete circuit within the MEFI 3 that can be set up that way. MEFI 3 is limited on its capabilities thou.

I agree with Speedy Gonzales, most likely a supply fuel line issue, return has nothing to do with low fuel pressure.

I use internal hose support springs on lines I think could kink or suction closed . They work great .

He's just running his mouth like always,

Of course I was in your mind, but does that really count thou ? You can post whatever you want but in the industry that what counts. For me it really does not matter cause you do not even work on boats nor support the boating industry in anyway.

Just by pass over my posts PLEASE skip over them Ken, Make pretend Im not even posting on OSO. Your third grade comments as usual. Ken, If you can skipped over all my posts I am sure you will feel better doing so but for some reason you can not. Most likely a lot of leaning education for you from my postings .

Back to REV --- for the record My posting to REV was for him not to get misdirection away from his real issue if he had a no start comeback in due time. Basically was it in a nut shell about the ecm shutting down,

You were clearly bashing the 2 guys tying to help REV, you keep serving up the cool-aid to the new guys and the ones that don't know any better on how your Super Tech, most can see through your BS, post a pic of the newly designed 2020 distributor rotor, I'm sure their flying off the shelf. sorry REV for the hijack I wont post here again
john johm john john

EDIT: and why the Mod's allow you to peddle your stuff on here without being an advertiser , you're not even a paying member.

I have fixed quit a few things on my boats over the years, without ever actually figuring out what the real problem was ,so dont feel bad.