1989 mercury 50hp 2 stroke bad/odd idle issues

[Jkcckc2002]

I am still trying to get this outboard running correctly. I have gotten It running but it will not idle under 1000 rpm while in the water. Also it will not stay running when shifted in to gear, well it doesnt just die, it just sputters out slowly. In all of my trouble shooting and testing of the idle issues ans link and sync problems, i have concluded that it can not run unless the timing is advanced all the way to 9* btdc. Yes btdc. When trying to set it any where near the correct idle timing it doesnt even attempt to start. I had disabled the throttle shafts from cam and used the fast idle to advance the timimg untill it would start. From there i would slowly retard timing and check it. All 3 cylenders are firing, but wont run.

With the throttle cam back together i have ran the engine, to adjust it to the best running idle i can get. It will only run when the idle screw is between 1.25 and 1.5 turns out. Any more or less nothing.

When i pull the plugs they are wet, more wet than i think they should be. They are wet enough to form a drop on the plug, but not drip. So i have attempted to see where any extra fuel could come from. It is not flowing from the venturi pick up or the enricher. I used earplugs to block them just to be sure, although not at the same time . It could be correct and i just dont know what i am lookimg at.

My thinking was that more fuel would equal more advance timing to run.....

ok that ended up alot longer than i expected. Thanks for reading all that for those who hung in there.

 

[racerone]

Not sure why / how you are adjusting the idle timimg ?-----You only set the maximum idle timing on that motor.------You do not move / adjust the spark timing at idle.-----Have you tested compression on this motor ?

 

[Jkcckc2002]

The compression is 115-120-120 top to bottom. I have done the link ans sync procedure by the book at least a dozen times. The max timing was set fitst, then throttle stop. Then secondary pick up. The primary is not adjustable, i know that. The engine would not hit until the butterflies in the carbs were beginning to open. It would fire just not ignite. The only way to get it to run would be with the carbs opening. I was never trying to set the idle timing the engine would never run unless the fast idle lever was up, and it would promptly shut down when returned. I was trying to get the idle rpms down bu not having more fuel air going into the engine with it running. Along the way i realized it is way out of specs.

 

[Jkcckc2002]

No Title

The specs for the engine

 

[Jkcckc2002]

I finally gave in a brought it to an outboard mechanic. While i was there we went through what was done to the engine and what trouble shooting steps i had done. He was pretty much stumped at it also. So he is going to read up on that specific engine and do what hw can for me. Ill keep it updated as to what he says.