MS-290 rebuild

[a. palmer jr.]

because the depth of the jug I was not able to use my ring compressor, used a pocket knife to work it in around the perimeter. Little built of a bevel there so that was the easy part so far! Hopefully the rings stayed where I put them!

If it went in and you didn't hear a pop it probably is okay..

 

[a. palmer jr.]

I just finished my latest 390 conversion, went fairly well, don't notice it having any bad habits. I went with a muff mod, carb richened up a bit, used Motoseal instead of Dirko this time...I'm breaking it in right now, later I'll lean the carb out a slight amount and see if it rpms a little better..

 

[Stihl_Boss 83]

I just finished my latest 390 conversion, went fairly well, don't notice it having any bad habits. I went with a muff mod, carb richened up a bit, used Motoseal instead of Dirko this time...I'm breaking it in right now, later I'll lean the carb out a slight amount and see if it rpms a little better..

 

[Stihl_Boss 83]

Did you use the 029 carb, if so how many turns out did you set the high and low? I was told 1-1/4 on the high and low end but want to get more feed back. This is my first time doing the conversion so not 100% on the tunING as it won't fire as of yet...

 

[a. palmer jr.]

Mine was a 290 carb with the scoop on top hooked to the air filter. The 029 carb would be as good or maybe better. I took the limiters out of the carb and initially turned the screws at 1-1/4 turns out from lightly seated. I cleaned the carb first and put a new kit in it so it would be operating at it's best.

 

[Stihl_Boss 83]

Mine was a 290 carb with the scoop on top hooked to the air filter. The 029 carb would be as good or maybe better. I took the limiters out of the carb and initially turned the screws at 1-1/4 turns out from lightly seated. I cleaned the carb first and put a new kit in it so it would be operating at it's best.

 

[a. palmer jr.]

You can always try an extra quarter turn if it is difficult to start. Also, did you use an aftermarket fuel line? If you did you might check it for kinks...the AM fuel lines for this saw aren't very good.

 

[Stihl_Boss 83]

Ok

You can always try an extra quarter turn if it is difficult to start. Also, did you use an aftermarket fuel line? If you did you might check it for kinks...the AM fuel lines for this saw aren't very good.

 

[Stihl_Boss 83]

I'll give it a shot in the morning and she how it goes. It sounds like it wants to go so we'll see how I make out tomorrow. I'll check back here in the morning and give an update. Thank you for your help...

 

[Stihl_Boss 83]

Still at a loss with this saw. The decompression valve was one issue I had but being that ill never used it I pulled that out and plugged it. But I'm not getting any closer to getting it to fire. Im beginning to wonder if maybe that no name plug I got with the bbk may be one of the issues. I used a spark tester and it's getting spark but could I be getting spark with a bad plug?

 

[a. palmer jr.]

Still at a loss with this saw. The decompression valve was one issue I had but being that ill never used it I pulled that out and plugged it. But I'm not getting any closer to getting it to fire. Im beginning to wonder if maybe that no name plug I got with the bbk may be one of the issues. I used a spark tester and it's getting spark but could I be getting spark with a bad plug?

It's possible. If you have the old plug you can try it. Have you tried putting about a half a teaspoon of fuel mix directly into the sparkplug hole and trying to start it? That would eliminate the entire fuel system and you'd only have compression and spark that would be tested. If it doesn't fire then, you either have an electrical problem or an engine issue, air leak or low compression..

 

[Stihl_Boss 83]

It's possible. If you have the old plug you can try it. Have you tried putting about a half a teaspoon of fuel mix directly into the sparkplug hole and trying to start it? That would eliminate the entire fuel system and you'd only have compression and spark that would be tested. If it doesn't fire then, you either have an electrical problem or an engine issue, air leak or low compression..

It was the plug. I put the old plug in and it fired right up. Just have to tune it which I never did with a fresh top end so I'm worried about it being too lean.

 

[a. palmer jr.]

That's easy to do. Just get it to idle really good then turn the screw out a little bit, maybe an eighth or so. Same with the high speed, don't let it achieve max revs, richen it back a bit then try it in some wood. You'll know if you have it too rich, it'll bog somewhat. I still have to do that to a couple of my saws..