1976 Evinrude 25 starting problems

falconduvent

Cadet
Joined
Aug 13, 2007
Messages
7
i have a 1976 Evinrude 25 that is under the weather.

First it ran, then after a few days, it carboned up on me.

Cleaned plugs, to no avail.
Discovered that oil gas ratio was supposed to be 50:1 instead of 32:1, so fixed that.
Cleaned the carb and it ran fine again, took it out, after 10 minutes wide open, began to hesitate and slow, by the time i got back to the dock, it was shaking and coughing. the #1 plug was badly carboned and the #2 plug was fine. Cleaned the plugs and tried again, didnt start, tested spark, found the #2 plag was shot. Looked up spark plug advice, found out i had the wrong plugs, rplaced them with the right ones, J4C @.030 from champion. Tried it again, engine coughs, take off choke, it wont start, floods. Any suggestions?
 

wbeaton

Commander
Joined
Jul 30, 2006
Messages
2,332
Re: 1976 Evinrude 25 starting problems

Are you getting spark in both cylinders? Have you cleaned and set the points (.020")?
 

falconduvent

Cadet
Joined
Aug 13, 2007
Messages
7
Re: 1976 Evinrude 25 starting problems

I have a fat blue spark on both cylinders, points set at .030, as recommended by Evinrude. The carb is in excellent condition, and was overhauled and cleanded 2 days ago. The low speed jets, (there are 3) were slightly obstructed and the main jet was blocked. Now it doesnt start because it floods right off the bat. The motor ran fine up untill a few days ago.
 

wbeaton

Commander
Joined
Jul 30, 2006
Messages
2,332
Re: 1976 Evinrude 25 starting problems

Plug gap is .030. The point gap is .020.

If its flooding you still have a carb problem. Did you rebuild the carb or just clean it? Sounds like either the float needle isn't seating or the float is sinking or is not set correctly. Buy a rebuild kit if you didn't the first time and clean everything again.
 

BoatBuoy

Rear Admiral
Joined
May 29, 2004
Messages
4,856
Re: 1976 Evinrude 25 starting problems

Since one plug fouled and the other one didn't, it sounds like maybe your fuel pump is leaking fuel into the cylinder where it's mounted. Pull the pump off and squeeze the primer bulb on the fuel line and see if fuel comes out the back of the pump.
 

falconduvent

Cadet
Joined
Aug 13, 2007
Messages
7
Re: 1976 Evinrude 25 starting problems

fixed it. The final issue was that when i put the carb back onto the engine, i neglected to turn the needle valve for the low speed jets in the proper amount. I compared it to a working motor like mine and adjusted it accordingly. when i tried starting it again, it took a little adjusting while rnning to find the sweet spot between too rich and too lean. i disconnected the control nob for the valve so it will not be in danger of accidental maladjustment. Thanks for your insight.
 
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