MS261 Carburator Basic Setting

[pyankura]

I have the shop manual but I am a bit overly cautious. From what I read, I turn the H screw all the way (CW) to its seat. Then back it off 1.5 turns (CCW)....The reason I ask is I cannot leave well enough alone and tried to Tim Taylor it and pulled the limiter cap. Well, long story short, I lost my position as I was trying to be careful and not lose the position and I did.

The reason I was pulling was not to make it faster but to slow it down or richen it up. I read here some folks were finding very lean conditions from the factory and the limiter caps stop from correcting it. I bought a tach in preparation (works connection) to make it right. Bad thing is I am not sure what proper is, only that Stihl recommends 14,000.

What I think I know is:

Basic setting checking rpms

Tune till it 4 strokes out of the cut while watching the rpms

I think I can get it but want some expert advise. I can take abuse, I got thick skin!:msp_unsure:

 

[tgerloff92]

Put your limiter cap back on no matter where your screw is. Get a 2.2 millimeter allen(2 will work) and put it right in the center of the limiter and adjust it this way, adjust 4 or 5 clicks past where you want your saw so that you can turn it back to your desired setting with your screwdriver so while in the field you can richer it up a bit more if you need it.

 

[blsnelling]

The 261 doesn't have limiter caps like that. Just richen it up until it's way rich, then lean it out until it's about 13,800.

 

[tgerloff92]

My 261 only let me turn it one full turn.

 

[pyankura]

Mine only allow .5 to .75..I tried what I read in another thread drilling out the center and using a 2mm allen. I turned on it pretty good was afraid I would break the head off. However, I can pop the cap off now cause I taped it and can use a small bolt to pull it out anytime and just enough to use the allen. So, by turning it in all the way to seat then 1.5 out ccw is basic setting, correct??

I saw this thread:

http://www.arboristsite.com/chainsaw/113538-5.htm

and the 1:13 min video really cleared things up and also the thread. Any tips are very much appreciated!

 

[saxman]

The 261 doesn't have limiter caps like that. Just richen it up until it's way rich, then lean it out until it's about 13,800.

I agree, I opened my muffler up a bit and set it to 13,800 by the tach. Seems to have more grunt there. Before I touched anything it was a tad over 14,000 and had a bad throttle hesitation . That is all gone now and it is a very good saw, maybe not the best "sideways balance" but I can live with it. Perhaps Brad or Randy can fabricate some kickstands for us 261 owners:hmm3grin2orange:

Steve

 

[SCHallenger]

Limiter on H needle of MS261

Mine only allow .5 to .75..I tried what I read in another thread drilling out the center and using a 2mm allen. I turned on it pretty good was afraid I would break the head off. However, I can pop the cap off now cause I taped it and can use a small bolt to pull it out anytime and just enough to use the allen. So, by turning it in all the way to seat then 1.5 out ccw is basic setting, correct??

I saw this thread:

http://www.arboristsite.com/chainsaw/113538-5.htm

and the 1:13 min video really cleared things up and also the thread. Any tips are very much appreciated!

Even with the alloy jacket removed from around the H needle you will find 2 plastic tabs at the base of the needle which will bump into an alloy rib located within the alloy sleeve which houses the jacket (which you have successfully removed). Looking at the external surface of the jacket, you will see a rib which bumped into the internal rib on the sleeve & limited your adjustability originally. The best way to allow for unlimited adjustment is to grind off the internal rib (very carefully--don't get impatient!!) & finish the job where the plastic tabs would bump the rib with some small needle files (1/2 round works best). Once that internal rib is gone you can use the 2mm allen wrench to back the H needle out entirely. You will now find that those little plastic tabs at the base of the needle index into the alloy jacket which you are now holding in your hands. Now all you have to do is slide the needle with tabs intact into the alloy jacket & screw whole assembly in until it seats lightly. You now have full & unlimited adjustment of your H needle & can proceed to back it out about 11/2 turns which should be plenty rich & proceed to adjust & tune. Many threads on here are very well done on that subject. I remember one by Brad Snelling & one by Andyshine that were very clearly done & included vids.

 

[H 2 H]

I agree, I opened my muffler up a bit and set it to 13,800 by the tach. Seems to have more grunt there. Before I touched anything it was a tad over 14,000 and had a bad throttle hesitation . That is all gone now and it is a very good saw, maybe not the best "sideways balance" but I can live with it. Perhaps Brad or Randy can fabricate some kickstands for us 261 owners:hmm3grin2orange:

Steve

I'm glad had a towel handy to clean my screen off on that one

 

[blsnelling]

It's the 346 and 550 that need a kickstand. The 261 sets fine. If you want more, then there are factory options, unlike for the Husky.

 

[saxman]

It's the 346 and 550 that need a kickstand. The 261 sets fine. If you want more, then there are factory options, unlike for the Husky.

I appreciate that comment Brad, I was afraid you had moved over to the "dark side" completely

Steve

 

[pyankura]

Well I tuned the saw to day by what I heard in the videos and what I've learned here. I started with the H screw 2.5 turns out and ran it through a log, 4 stroking bad. I went in .5 turns and it got better, then a bit more til it stopped then backed it out a but so still 4 strokes but faintly!

I basically did it by ear because the works connection tach, was not working well. I noticed when I first connected it I would blip the throttle and it was at like 11k rpm, maybe ok. So when I was tuning it would tach out at like 19.9k rpm, so I thought it was not right and move on. I tried a bunch of coils low on the plug wire and high, the 5 like it said low and high, same same.

So what I've learned is to tune by ear, very good guide. And my saw I bought used in very good condition may have already been set properly from the user. I noticed when I took limiter cap out again looking for the spline there was none like I've seen in pictures. I did not look ground or files or anything, just not there! The limiter cap did limit movement but not by hit the spline. Saw runs great again, actually was never a problem and now I go make firewood!