Which electric fuel pump Vortec longblock?

SDB

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Aug 13, 2019
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Putting a reman Vortec headed 5.7 longblock in my 1992 Rinker Captiva 206 and need to run an electric fuel pump. Which one is a good choice and how to wire it?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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47,295
use the search function on wiring. must be a few hundred posts showing proper wiring

I would get a Carter P4389 universal marine electric fuel pump (about $65)

you will need a VF4 relay (about $3) and an oil pressure switch (about $10)
 

hnt

Petty Officer 2nd Class
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Dec 31, 2010
Messages
104
I used a Holley Red - Marine pump when I did the conversion. I too had a mechanical pump prior. One thing to remember is that electric fuel pumps do better pushing fuel than pulling fuel. I had problems with losing prime when I first switched using a Carter pump. When I switched to a Holley Red it seemed it solve the problem but it reemerged later. You need to be careful not to use too fine of a pre-filter for one thing I think 20-or 30 micron is max.. I also re-plumbed mine so the the Mercruiser water separator was after the fuel pump thinking I was getting cavitation. As it turned out I was getting a tiny air suction leak at the Floscan sensor before the fuel pump that during prolonged idle would allow the fuel pump to loose prime and starve the VST tank so the engine would die. It only did this at idle and there was never any gas leak. (A section of clear tubing to insert in the fuel line is how you find small air leaks BTW) Once I found the problem it has been flawless and I have tried it with both pumps (although I still am using the Holley Red). I'm sure the air leak was present with the mechanical fuel pump too but they seem to handle very small suction leaks better I think. Others have covered the wiring and the oil pressure safety switch. Good luck. The Vortec heads make a very noticeable difference in performance Good choice!!!.
 

SDB

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Aug 13, 2019
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10
Hnt....good info...thanks. I've been combining a list of parts to get and gather in preparation for yanking the motor
 

Rick Stephens

Admiral
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Aug 13, 2013
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6,118
I used the Airtex pump that was OEM when my motor was used by Mercruiser. That let me get any fittings, mounts and the stainless preformed fuel line between pump and carb.

Using the factory mount puts the pump on the end of the head, after the water separator. I had the same issue with the fuel draining back down and losing prime. So I added a marine check valve between separator and pump.

fuel system.jpg
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
I wish I had used the Mercruiser fittings and lines. I became a virtuoso line bender making up lines for two different carbs and two different fuel pumps.
I'm so bullheaded, I had to do it myself. Waste of time and money in the long run, but they are done and nice now!

I ran an Airtex for 2 years. Pulled it when I had a different problem. I'm sure now that I didn't have to toss it. But it's gone now.

I wasn't satisfied til I got a Holley Marine pump, which is rated for everything my carb could demand. It seems not to drain back, much if at all. If I don't run the boat for a week or so I get fire in 3 or 5 seconds of cranking. If I watch the fuel pressure gauge it jumps around for a good 10 or 15 seconds til the bowls are full and things get steady. But the engine can't tell, so it must be getting fuel.
 
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