evinrude throttle issue

[axel2009]

I have a 1979 35hp evinrude. I was having issues with it dying at idle and not wanting to run full throttle. I friend of my rebuilt the carb and did a cam adjustment as well as some linkage adjustments. took it out yesterday for the first time and the idle issue is solved, however the throttle issue isnt. What happens is when I move the lever to full throttle it only appears to be running half throttle. Sometimes you will hear the engine sputter a few times and then it will run full throttle for awhile and then suddenly goes back to half throttle. I am not mechanically inclined so is there anything I can check before sending it back for repairs? thanks for looking!!

 

[tashasdaddy]

Re: evinrude throttle issue

contaminated carb.
Ethanol and fuel lines
replace all fuel line with Alcohol resistant lines. Ethanol deteriorates, the rubber lines, then they start to sluff off on the inside, going directly to the carbs. Settling to the bottom of the bowl. Contaminating the carbs high speed jets. clean a rebuild carbs, flushing fuel line before connecting to carbs.

 

[axel2009]

Re: evinrude throttle issue

The carb was rebuilt about a week ago. According to the previous owner, he said he never used ethanol and never left fuel in the motor. He would always disconnect the fuel line from the motor and let all the fuel burn out. Could this be a spark issue in one of the cylinders since it only occasionaly runs full throttle?

 

[axel2009]

Re: evinrude throttle issue

Update
I pulled both plugs and one looked really clean and the other had a bunch of black crap on it. I went and got new plugs and installed them and instantly I noticed the engine idle better. I tested the WOT and it reved up without missing a beat so I am hoping I have the problem solved. My question is this. I pulled the new plugs after the engine test and noticed both plugs were wet. I just want to know if this is normal or might I have another issue too

Thanks