mercruiser 305 fuel pumps

[90baylinerV8]

i have some good aftermarket fuel pumps fromn my old play truck. can i replace the pump in the boat with the auto fuel pump or is it a no no like the carb is.

 

[zbnutcase]

Re: mercruiser 305 fuel pumps

A no no

 

[Bt Doctur]

Re: mercruiser 305 fuel pumps

the mechanical pump use a diaphran that the bottom of must be exposed to atmospheric pressure because it goes up (sucks air in) and down (pushes air out).Thats why there is a small hole in the base of the casing. Marine use requires this hole have a hose fitting to carry any fuel from a ruptured diaphram up to the card and dump it in there instead of in the bilge.

 

[Fireman431]

Re: mercruiser 305 fuel pumps

Unless you are talking about an electric fuel pump, than that is a super no-no. Can you imagine a line coming loose and dumping fuel non-stop into the bilge and then overboard?

 

[90baylinerV8]

Re: mercruiser 305 fuel pumps

Unless you are talking about an electric fuel pump, than that is a super no-no. Can you imagine a line coming loose and dumping fuel non-stop into the bilge and then overboard?

the aftermarket pump i have is threaded like the oem. it does not have slip on nipples that use clamps. the only visual difference i see without pulling the one out of the boat is mine is polished aluminum and my fittings are not in the same locations. so i would have to run two new fuel lines.

 

[picklenjim]

Re: mercruiser 305 fuel pumps

To be safe it needs to have a place on it to connect a hose on to run to the carb in case of a diaphram rupture. Notice the brass tube on the marine carb in the picture.http://www.jegs.com/i/Holley/510/712-454-13/10002/-1?parentProductId=751733

 

[Eric 3.7LX Alpha 1]

Re: mercruiser 305 fuel pumps

the mechanical pump use a diaphran that the bottom of must be exposed to atmospheric pressure because it goes up (sucks air in) and down (pushes air out).Thats why there is a small hole in the base of the casing. Marine use requires this hole have a hose fitting to carry any fuel from a ruptured diaphram up to the card and dump it in there instead of in the bilge.

What he said.

If your current pump does not have that small line connected from the bottom of the fuel pump to the carb, (not the inlet and outlet fittings) then that pump you have now might be non marine which is not good.