Using Electric Fuel Pumps

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John Clarke
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Using Electric Fuel Pumps

#1 Post by John Clarke »

Hi All
Ref what David Jones said on the other Crankcase Oil Level post.
The Stock 356 mechanical Fuel Pump can actually leak fuel through to the Crankcase. Leading to Diluted Oil and an obviously High Oil Dipstick reading. Does the use of an Electric Fuel Pump (For Carb Priming) in conjunction with the stock mechanical pump, Increase the risk of Gas in the Crankcase Oil?
Cheers Jay.
 

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David Aronson
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Re: Using Electric Fuel Pumps

#2 Post by David Aronson »

I would think that if the pressure is low, it would not increase the chance. The problem is finding a pump that is low pressure. I found a low pressure 6v pump on amazon. 5psi
https://www.amazon.com/gp/product/B07GN ... UTF8&psc=1
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Dick Weiss
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Re: Using Electric Fuel Pumps

#3 Post by Dick Weiss »

The output of the electric pumps shown are too high for 356s and 912s; Should NOT exceed 2,8 to 3,0 psi.
Pressure regulators may not work, either.

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Bruce Smith
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Re: Using Electric Fuel Pumps

#4 Post by Bruce Smith »

Dick Weiss wrote: Mon Mar 27, 2023 11:08 pm The output of the electric pumps shown are too high for 356s and 912s; Should NOT exceed 2,8 to 3,0 psi.
Pressure regulators may not work, either.
Heed Dicks advice, 8 psi is way too much and 5 psi still may have a chance at overpressuring the float valves. 2-3 psi is good, and if you're using a regulator to get there it should be measured over a range of conditions (i.e. voltage swings).
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Re: Using Electric Fuel Pumps

#5 Post by Pete Indelicato »

I had issues with an electric fuel pump--never could figure out what pressure to run it at--read that 3.5 was ideal, it would run fine around town at lower rpms--but on the highway after about 5 mins. it would starve the engine. I tried different pressures but was worried about flooding the crankcase with fuel. Went back to mechanical pump and all is good
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Chuck Allard
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Re: Using Electric Fuel Pumps

#6 Post by Chuck Allard »

I had an electric fuel pump on one of my 356s with a pressure reducer that was supposed to cut the pressure down to 2.5 lbs. Car ran fine for a few years then started starving for fuel on the highway at times. It turned out that the adjustable regulator was sticking at times. After idling for a few minutes by the side of the road it would run fine again - for a few days. I replaced the pressure regulator and it ran fine again for a few more years. I finally went back to a factory fuel pump.

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Don Gale
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Re: Using Electric Fuel Pumps

#7 Post by Don Gale »

Just to confirm, will a 912 factory original mechanical fuel pump work on older engines, say a 1958 1600 Normal?
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David Jones
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Re: Using Electric Fuel Pumps

#8 Post by David Jones »

Yes it will Don.
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Martin Benade
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Re: Using Electric Fuel Pumps

#9 Post by Martin Benade »

You just have to adapt the fuel lines a bit
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