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1979 Evinrude 25 HP won't start

A

Andrewa

New member
Model # 25904R

I had it out on the water a few times this year after rebuilding the power head. It ran great.
A couple times it bogged down to almost no power when at full speed. Last time it did it, I was able to drive idle speed back to the landing and shut it off and it doesn't want to start since.

Has new plugs (spark jumps over a half inch gap on both), good compression (both cylinders have same psi) , new fuel pump, rebuilt carb, new lines, tank, bulb, etc.

If fires with starting fluid so it seems as though it's a fuel issue based off my knowledge. I also put a few drops of mixed gas into the spark plugs ports and it fires then. Won't stay running though because seems to not be getting fuel.
At the carb I don't really smell gas, but the bowl is full. I removed the carb Looked through carb port to see reed valves and from what I can see they look ok...

Needless to say I'm stumped. Any well experienced and knowledgeable advice needed please.
 
Id go through the fuel lines and carbs again. Sounds like it sucked up some gunk.
If you can, try a different tank and hose with fresh fuel.
 
Ok guys, I really appreciate your advice, and taking the time to respond with your knowledge!!!

It just so happens I figured out the problem.
Here's what I did:

Cleaned carb (again, for the 3rd time) as I've read it can take a couple times on occasion, the motor had sat for years it seems, and that's what I found it to be this far!!! Hopefully it stays running!
 
I do have another question maybe you know the answer,
So I bought a new model fuel tank, a plastic 3 gallon self venting supposedly, and when in the heat the thing looks like a balloon about to pop!
Anyways, are these newer tanks junk? I don't trust the thing. I like the old steel ones. Should I use one of those instead???
 
James in Canada said:
Does it have a vent that you can open/close in the middle of the filler cap?
Click to expand...

No, it's apparently built into the tank. It's a small hole beneath the fitting on the gas tank. So I'm wondering it these new tanks actually vent enough to allow a gas guzzler to operate properly
 
I think probably the vent only opens when you have a hose attached to the tank.
That's the way the metal ones worked.
Was the hose attached when the tank was swelling?
Does the pressure release when you attach the hose?
 
Andrewa said:
No, it's apparently built into the tank. It's a small hole beneath the fitting on the gas tank. So I'm wondering it these new tanks actually vent enough to allow a gas guzzler to operate properly
Click to expand...

Can the tank support a gas guzzler is a pretty relative question.
I guess the answer would be "does the tank start to implode after running
at full throttle for a while?".
 
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