Why Electric Fuel Pump??

[etbill52]

I have a 1977 Sea Ray, with a Mercury Mercruiser (GM) 6 Cyl. (Stern Drive) 165 HP
Motor S/N 4610110, I think the motor is also a 1977.
It has the regular fuel pump on the motor, but someone has installed an electric pump in the line between the gas tank and motor mounted pump.
Should this be there, pumping fuel to the other pump? Also the wire gets heated up after running a while on the electric pump. Should I take it off and just run the one pump, or check and see if it is bad being the reason the electric one is on it?

 

[Bondo]

Re: Why Electric Fuel Pump??

My Guess is,........

The original fuel pump Quit,+ some Moron added the electric 1 in line.....

I'd pull them Both,+ replace the Original 1........

 

[rodbolt]

Re: Why Electric Fuel Pump??

I am with Bondo, odds are high the electric pump is not mounted nor wired per USCG and ABYC regulations.

 

[wire2]

Re: Why Electric Fuel Pump??

Some electric pumps are made to operate with a return line to dump exess pressure. Otherwise, it will pump full tilt, heating the fuel and drawing a lot of current.

As Bondo-o suggested, make the original design work. The mechanical pump probably just needs a diaphragm kit.

 

[etbill52]

Re: Why Electric Fuel Pump??

Thanks everyone for your replies, thats what I will do replace the original pump, and remove the electric one. The wire heating up has been my concern, I checked and it don't have a return line so it runs all the time the key is on

 

[rodbolt]

Re: Why Electric Fuel Pump??

see
suspicion confirmed.
its not wired correctly.
if you wish to keep it make sure its USCG approved for marine use and wire it through an oil pressure switch so anytime the engine is off the pump is off make sure both supply and grond leads are sufficient to carry the current draw. fuse it about 3 amps higher than the current draw and make sure the fuel pressure stays between a minimum of about 5 psi and a max of about 7 psi.

or eliminate it and replace the original.

 

[Hammerhead2]

Re: Why Electric Fuel Pump??

I have 1977 Mercruiser 140 hp, 4 cyl chevy with a mechanical fuel pump.
I would like to replace with an electric fuel pump.

What's the best way to proceed?

Thanks in advance

 

[etbill52]

Re: Why Electric Fuel Pump??

see
suspicion confirmed.
its not wired correctly.
if you wish to keep it make sure its USCG approved for marine use and wire it through an oil pressure switch so anytime the engine is off the pump is off make sure both supply and grond leads are sufficient to carry the current draw. fuse it about 3 amps higher than the current draw and make sure the fuel pressure stays between a minimum of about 5 psi and a max of about 7 psi.

or eliminate it and replace the original.

I removed the electric fuel pump, connected the fuel line back together, cranked the motor original fuel pump put out a good flow of gas, put the boat in lake, it ran good, so there was not anything wrong with the original fuel pump. I have no ideal why any one would want 2 fuel pumps. Thank every one for your feed back.

 

[Dunaruna]

Re: Why Electric Fuel Pump??

I have 1977 Mercruiser 140 hp, 4 cyl chevy with a mechanical fuel pump.
I would like to replace with an electric fuel pump.

What's the best way to proceed?

Thanks in advance

PM etbill52, I think he has one for sale