1991 70HP Evinrude vro 2 stroke running rough .

[diamonddog]

I bought a 1991 70hp Evinrude vro 2 stroke. I'm having a couple of problems. I have trouble getting it started and when it does It idles rough. I pull the plugs and two looked good but third had a lot of carbon build up. Can somebody help me?

 

[boobie]

Re: 1991 70HP Evinrude vro 2 stroke running rough .

Do a compression test first and then a spark test. Use an open air gap spark tester set at 7/16 ".

 

[diamonddog]

Re: 1991 70HP Evinrude vro 2 stroke running rough .

I did the compression test all three cylinders were 115lb and the spark test was good.

 

[Steve73]

Re: 1991 70HP Evinrude vro 2 stroke running rough .

Possible stale fuel. Carb could also be dirty. Possibly fuel pump or plugged fuel filter. Sounds fuel related.

 

[boobie]

Re: 1991 70HP Evinrude vro 2 stroke running rough .

If a carb job hasn't been done on it for sometime, you may want to think about that.

 

[diamonddog]

Re: 1991 70HP Evinrude vro 2 stroke running rough .

I rebuit the carbs and still is hard to start i checked the stator and i'm getting 409 ohms resitance and 136 volts cranking amps.

 

[Steve73]

Re: 1991 70HP Evinrude vro 2 stroke running rough .

Service manual will tell you your resistance ratings for your stator. How is the positioning of the choke valve? Is the fuel fresh? Is the fuel being adequately fed to the carb?