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Electrical Fuel Pump

ronrw2b2

New member
I need to replace my mechanical fuel pump on my carburated 351w and I was thinking of switching to an electric pump. Is there any difference between an auto pump and a marine electric pump?
 
Fuel, electrical and ignition components on a boat MUST be "MARINE", i.e. USCG approved... else... safety issue and insurance won't pay if you use automotive parts and things inevitably go bad. Installation of an electrical fuel pump requires not only the use of a MARINE electrical fuel pump, but that it be wired so that the power to the fuel pump cut off if there is no oil pressure. Many applications are wired so that the fuel pump gets power during cranking additionally. There are USCG requirements for the fuel connections that you must observe.

You are probably better off with an OEM mechanical (marine!!!) pump per "johnnygjr" above. Two bolts, one gasket, two existing lines... done.
 
I need to replace my mechanical fuel pump on my carburated 351w and I was thinking of switching to an electric pump.
I would also!

Is there any difference between an auto pump and a marine electric pump?
Yes!

You can safely install a Marine approved carburetor style (i.e., 4 to 7 psi max) electric fuel pump.
The N/O LOP (Normally Open .... Low Oil Pressure) switch is a requirement.
I would use a relay that is triggered by the LOP S.

Reason: If Engine oil pressure was to drop below the N/O LOP Switch "closed" pressure, the relay would interrupt fuel pump power.
The mechanical fuel pump stops pumping fuel when/if the Egine was to stall........... whereas (in the absence of a N/O LOP Swtich) the electric fuel pump would (key word "would") continue to pump fuel when/if the Engine was to stall!


The "start-by-pass" is not a requirement, but is necessary!
A "momentary" helm switch (in lieu of the "Start-by-pass" circuit) gives us the option of priming the carburetor fuel bowl prior to Engine cranking!!!!
This aspect alone makes the installation well worth doing!!!! :D


NOTE: this must be a "momentary" switch as to NOT violate USCG rules!




.
 
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You can safely install a Marine approved carburetor style (i.e., 4 to 7 psi max) electric fuel pump.
The N/O LOP (Normally Open .... Low Oil Pressure) switch is a requirement.
I would use a relay that is triggered by the LOP S.

Reason: If Engine oil pressure was to drop below the N/O LOP Switch "closed" pressure, the relay would interrupt fuel pump power.
The mechanical fuel pump stops pumping fuel when/if the Egine was to stall........... whereas (in the absence of a N/O LOP Swtich) the electric fuel pump would (key word "would") continue to pump fuel when/if the Engine was to stall!


The "start-by-pass" is not a requirement, but is necessary!
A "momentary" helm switch (in lieu of the "Start-by-pass" circuit) gives us the option of priming the carburetor fuel bowl prior to Engine cranking!!!!
This aspect alone makes the installation well worth doing!!!! :D


NOTE: this must be a "momentary" switch as to NOT violate USCG rules!




.


Ricardo... I agree. I think the whole decision should hinge on the experience and ability of the owner.

BTW... the relay would need to be an "explosion proof marine grade" relay as well. AND new fuel lines to reroute the pump would need to also be USCG approved as well... again a skills and resource issue of the poster.
 
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