Hi All

I have to drop my tank to adjust my sending unit.  While I'm at it I want to install an Electric Fuel pump - noticed that some of you have done this mod.  Eventually I'm gonna swap a 500 into my '63 so Now's as good as any.  I read a good post on ModCad that used an oil pressure switch as a safety - a good idea! 


Can ya help me out with some ?'s

What pump is the 'right one'?  An OEM or something from Jegs or Summit?  What kind of flow #'s / current draw am I looking for?

I like the idea of gutting the stock pump and having it there just for looks - Is that difficult?  If I don't I'll need a block-off plate.  I assume I'll have to make one - probably not available

Will I need a return line (G4C Carb)

I'm not sure if the oil pressure safety switch is also a sending unit.  I want to keep my dash light functional.  I guess the safety threads into the back of the engine where the sending unit goes?  Will I be able to use both?  Will I have to 'Y' that hole and use 2 devices there?

What other things should I be planning for?  I intend to run it off a relay and will be running the safety.

Do I think too much??

Thanks for any help

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Comment by Russ Austin on July 26, 2015 at 11:43am

The running pressure of the mechanical pumps are in the 5-7 psi range. The carburetors will flood with anything higher than that.

Comment by Tony and Ginny 429 on July 25, 2015 at 6:02pm
I would think the fuel pressure from the stock fuel pump to the carb , would be much greater with the engine running than 5-6 lbs That are the cranking speed numbers to check the stock pumps output with a pressure gauge
Comment by Tony and Ginny 429 on July 25, 2015 at 1:48pm
There is no explanation , in the manual. , as to how you would check fuel pressure with the engine running ,only at cranking speed
Comment by Tony and Ginny 429 on July 25, 2015 at 1:44pm
Stock pump per the manual is 5 1/4 to 6 1/2 lbs , at cranking speed
Can the electric pump maintain that pressure over a long distance is my next though
These cars are longer than many ,from fuel tank to engine
Comment by Russ Austin on July 25, 2015 at 12:00pm

Forgot to mention the electric pump specs.  The pump I am running is fixed at 5-6 psi.  Depending on the pump you get, is what the psi rating is.

Comment by Russ Austin on July 25, 2015 at 11:50am

The stock pump specs are in the manual, as I don't know off hand.  Since the mechanical pump was gutted, there is a lot of fuel stored in the casing, when the engine is off.  With a stock pump, there is a lot less, as the pump diaphragm, valves, only let in a small amount of fuel at a time.

Its a theory that I'm going to work on today. Just bypass the gutted pump.

Comment by Tony and Ginny 429 on July 25, 2015 at 11:18am
Do you know the number of lbs of pressure the stock pump puts out , and the number of lbs the electric pump puts out ?
Is the electric pumps output adjustable ?
Comment by Tony and Ginny 429 on July 25, 2015 at 11:15am
Seeing as fuel would always be sitting in the stock fuel pump ,when car is idle ,even when not gutted ,not sure your theory is sound about this
The heat off the engine would effect the gutted or nongutted pump the same
Engine off for just 10 minutes seems like a short time for heat to affect the stock fuel pump
It may be taking the electric pump a minute to build the correct number of lbs of pressure , the fuel system requires to work as it should
Just my best guess
Comment by Russ Austin on July 24, 2015 at 10:42pm

I'm thinking that the gutted fuel pump is acting as a heat sink when the car sits in a parking lot. After she sits for over 10 min, and I go to start her up, she runs very rough, until I run about 1 minute of fuel through her.  I think that the fuel is becoming too hot inside the now empty mechanical fuel pump cavity.   I'm going to disconnect the fuel line from the mechanical pump, and just run it down the side of the pump. It wont touch, but will look stock unless you look real close.

I'll let you all know how it goes.

Comment by Russ Austin on February 15, 2015 at 9:45pm

I have gaskets for that, that I had made. Much better that the thin junk pushed on us by Fram.

email me at  russ85747@hotmail.com


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