Mercruiser V8 Fuel Pump: To place it here or to place it there that is the question?

[monette999]

Dear All,
​since I had to replace my GM V8 I was missing the mechanical push-rod actuator to drive a mechanical fuel pump.
So I thought use a Holley Red Line Fuel pump for carbs. 95gph. (my V8 has a single Rochester carb).

OK I thought s mart and positioned the pump in the same place as the mechanical fuel pump. Major advantage. I could used the OEM stainless steel fuel line without changing anything. See Photo:

Now here the downside: The pump is a push pump !!!

Holley sayslace the pump close to the tank. I am close to the pump!!! about two feet away. But I have the filter in front of it.
So the fuel will travel though the filter a slight loop up before it will be on the inlet port of the pump.
Holley says:Keep the pump away from the heat: That is a problem. The pump temperature will be always above the block temperature. What shall I do?
If the pump goes hot the is always the risk though thermal expansion of the pump. Will it keep the pressure when it gets hot????

Dear boat guys, please share your experience with me. I am sure that I am not the one who had this problem before.

Attached two pictures with the original setup a the new setup.

Thank you.

BR
Bob

 

[NHGuy]

That pump isn't marine rated, return it and search one that's able to go where the OE lines run. You'll spend the least money and time. Plus you'll be safer from the possibility of igniting fumes trapped in the engine bay.
They are out there, search marine electric fuel pump.
Also and very importantly, you'll need to wire up the oil pressure sensor shutoff so the pump won't run if the motor is off and the key is on.

 

[alldodge]

+1 with NHGuy and will add. The Holley Blue (70 gph) pump is marine rated. Your engine will use no where near half the 70 much less the 95 gph, I don't think you would like it if it where to use that much fuel $$$. If it were mine I would mount it out of the way and use barbed fittings and USCG rated fuel line. If you want to go a bit higher use AN fittings with braded line.

http://www.holley.com/712-802-1.asp

Edit: Suggest installing the fuel pressure regulator to keep it around 5 to 6psi. Also install the power to the pump through an oil pressure switch to protect the engine if oil pressure is lost

 

[monette999]

Dear AllDodge & NHGuy & Forum People.

My question is & was where to position the electric fuel pump.!!!!!!! I wonder if the position of the old mechanical fuel pump is good to go for an electrical pump.

I have already a extra spare pump. A Carter P4594. I have a Holley pressure safety switch connected in front of the pump.

May you make a proposal of an electric pump which goes 100% with the OE Lines.

I am living in Germany in Hessen and have limited resources to purchase equipment for V8 engines. This is not our displacement range.
The supply base is bad for special solutions.

At the position which you see on the picture I have estimated 150F on the pump. I am not convinced with the quality of Holley fuel pump.
I have not investigated the root cause. My assumption is a combination of self heating & external heat.

http://www.jegs.com/i/Carter/180/P4594/10002/-1.
Pumps are designed for carburetor engines and to operate in pairs when needed to meet your MEGA HP requirements for Street, Strip, Off Road, and Marine!


Thank you for you proposals & advices.

BR
Bob

 

[NHGuy]

Hi again. You still just can't use that in your boat. First off it's a push pump and you are proposing to place it in a pull position. So when you go to use it it will run out of fuel. Then what will happen? Maybe a big boom. Don't use it! Please!
So what happens if you place it in a push position? You will spend time money and effort rigging the non marine pump. And it still will be dangerous. Later, if you decide to do the right thing you will spend more money still...cut the waste and do it right once. The reason we aren't saying where to place it is because that is like advising you that it's OK. Its' not OK.
The other pump you mention is a car pump too.
Use marine only or unintended consequences are possible.
You cannot under any circumstances run auto electric parts in your boat engine bay, they are not spark proofed,.

 

[monette999]

Thank you NHGuy,

so what pump do you recommend and where shall I place a compliant electric marine fuel pump.
Please show me a suction pump which is heat resistant.

BR
Bob

 

[Volphin]

There is a Holley Red fuel pump that is marine rated. You can tell by the vent tube that is built into it. It's Holley Part Number [h=1]712-801-1[/h]

 

[Volphin]

Oh, and your mounting location is FINE. That's where mine is.