Fuel pump leak

[cschwass]

1976 Evinrude 75hp
I rebuilt the fuel pump and now it leaks out the back. There is a small hole near the top rear (breather hole??) that spits out gas when the motor is running.

Do I have a tear in the diaphram? Any thoughts?

 

[borz170]

Re: Fuel pump leak

What did it do prior to disassembly? Did you put it back together the same as it was? I have had similar problems with the same pump. I had to screw with it, movint the outside plate (that the in fuel hose connects to) back and forth, tightening the screw hand tight, squeezing the ball, and doing it again until it stopped. Try that...

 

[ezeke]

Re: Fuel pump leak

Take a look at the first thread at the top of the main page. There are pictures and diagrams that may help.

The back of the pump is separated from the rest of the pump by a full membrane that moves back and forth with the pulse from the engine. Gasoline should not reach the back of the pump because of the membrane.

Is it possible that you switched the fuel line and the pulse line?

The picture is the property of Theoutdoorsman

 

[cschwass]

Re: Fuel pump leak

Thanks for the reply's.

I don't think the lines are switched, only because it fires and runs (roughly) so it must be getting gas. I'll have to disassemble and take a closer look at the membrane. There has to be a pinhole that is letting gas through.

What is the correct thread sealant to use on the screws (to keep gas from passing through the screw holes, behind the membrane, and out the back)?

Thanks again.

 

[tashasdaddy]

Re: Fuel pump leak

that is why i replace important parts, rather than rebuild.