1972 Evinrude 25hp fuel problem

[cr9c1]

Long story short. I've rebuild the carbs and replaced all fuel lines in the engine compartment back to the fuel tank. I've had the cylinder covers that the small fuel hose connects to and the fuel pump connects to off, and replaced the gaskets. I've also replaced the fuel pump and the gasket behind it.

Everytime I run this engine I find a heavy concentration of fuel in the fuel pump area. When I run it with the cover off, I cannot see any fuel spraying out or coming out anywhere at all. But there is always fuel in this one spot. I'll dry the case out completley and wipe it down, take it out for a quick trip across the lake (a mile or so) and its all wet under the fuel pump again.

Anyone help me? Am I missing something? I've completely rebuilt the carb (including core plugs, etc), and replaced the fuel pump and fuel lines.

 

[samo_ott]

Re: 1972 Evinrude 25hp fuel problem

Interesting. Is the fuel in the lowest spot in the pan? as in it could be coming off the bottom of the carb and running to where the fuel pump is? and you only have 1 carb right as you say 'carbs'. You seem to have done everything that should be done. Are you sure it's raw gas?

Have you run it at WOT with the cover off and looked for spray/drips?

 

[cr9c1]

Re: 1972 Evinrude 25hp fuel problem

Yes. I meant "carb" and not "carbs". My mistake. I have run it at WOT and looked for spray, drips, etc. It is definitely fuel. I'm at a loss, I've done everything I possibly can. I'll do some more investigation I think.

 

[cr9c1]

Re: 1972 Evinrude 25hp fuel problem

So. Took the fuel pump apart today, got in a mess doing that. They can be difficult to put back together.

However, around 8PM tonight I finished putting it back together. It appears my fuel leak was located at the pump, and coming from 1 or 2 of the small vent holes in the pump body.

So I'll reassemble and try again tomorrow and see what happens. Anyone had the leaks at the small vent holes in the pump? Im leaning towards torn diaphrams but none of them looked torn upon inspection.