runs way to rich at elevation. Evinrude 9.9

[Bubbles Up]

Hi All,

I have a 1974 Evinrude 9.9, I fish a lot of high elevation lakes (3300 feet) I can't seen to to get this engine to run right even when I twist the rich/lean knob all the way to lean. I can run at full power sometimes it runs like a rocket other times it feels only like half power at best. Any ideas on how I can get a happy medium from living at sea level to the high country?

 

[F_R]

Re: runs way to rich at elevation. Evinrude 9.9

Being I'm down here in the swamp at sea level, I'm ignorant concerning high altitude. But I seriously doubt anything under 4000 ft is going to make any significant difference. Are you saying yours is OK at lower altitude?

You rhalf power sounds like one cylinder isn't firing.

 

[nwcove]

Re: runs way to rich at elevation. Evinrude 9.9

im at sea level, and thinner air at elevation should make your motor run lean not rich! sounds like F_R is on the right track with it dropping a cyl. or you need to clean/rebuild the carb. a quarter turn of the needle(s) should compensate for that little bit of altitude.

 

[boobie]

Re: runs way to rich at elevation. Evinrude 9.9

You're not high enough in elevation for that to cause a prob. As said above, look for something else.

 

[scipper77]

Re: runs way to rich at elevation. Evinrude 9.9

Check compression, check spark.

Also, on my outboard you only get one turn out of the knob to adjust the jets. Try pulling the knob off so you can turn without regaurd to the stops on the cowl.