Stihl 261 running problem. Need advice

[steven stern]

Hey guy! My stihl 261c will start and run fine for 1 tank of gas, after i refill the tank it will start up and die if i apply throtle or let it idle. Things ive checked are air filter and the plug. Im gonna check the spark arrestor buti doubt thats the problem. Any advice is VERY appreciated!

 

[steven stern]

I left the woods today with about 1/3 a load of wood cause the dang thing refused to start

 

[Mac&Homelite]

Does this have the m-tronic system? If not, was it very warm was it out at the time? I've had several problem with the carbs and restarting while warm with the same symptoms as you. It's particularly apparent if it is hot out. I've always found the issue to be in the carbs that the needle valve was a little high. Knock it down a tad and they seem to work fine in the warm temps them. Pretty annoyed when the saw won't restart isn't it. Drove me nuts on my ms361 for about a month before I finally figured it out.

 

[steven stern]

Does this have the m-tronic system? If not, was it very warm was it out at the time? I've had several problem with the carbs and restarting while warm with the same symptoms as you. It's particularly apparent if it is hot out. I've always found the issue to be in the carbs that the needle valve was a little high. Knock it down a tad and they seem to work fine in the warm temps them. Pretty annoyed when the saw won't restart isn't it. Drove me nuts on my ms361 for about a month before I finally figured it out.

Its got the mtronic setup, and it is about 90 degrees here. Its crazy annoying because it runs perfect then just quits!

 

[steven stern]

Does this have the m-tronic system? If not, was it very warm was it out at the time? I've had several problem with the carbs and restarting while warm with the same symptoms as you. It's particularly apparent if it is hot out. I've always found the issue to be in the carbs that the needle valve was a little high. Knock it down a tad and they seem to work fine in the warm temps them. Pretty annoyed when the saw won't restart isn't it. Drove me nuts on my ms361 for about a month before I finally figured it out.

And your right it only does it while its hot out

 

[lecbr600]

Does this have the m-tronic system? If not, was it very warm was it out at the time? I've had several problem with the carbs and restarting while warm with the same symptoms as you. It's particularly apparent if it is hot out. I've always found the issue to be in the carbs that the needle valve was a little high. Knock it down a tad and they seem to work fine in the warm temps them. Pretty annoyed when the saw won't restart isn't it. Drove me nuts on my ms361 for about a month before I finally figured it out.

That's very interesting!

A couple of questions:

- How did you figured it out? It's not easy at all!! Did you open carb while it was hot??

- What do you mean with "knock it down a tad"? Do you adjust lever highness?? Can you explain to me a little bit better? I'd appreciate it a lot

Thanks


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[Mac&Homelite]

That's very interesting!

A couple of questions:

- How did you figured it out? It's not easy at all!! Did you open carb while it was hot??

- What do you mean with "knock it down a tad"? Do you adjust lever highness?? Can you explain to me a little bit better? I'd appreciate it a lot

Thanks


Inviato dal mio iPad utilizzando Tapatalk

It was a lot, I mean a lot, of trial and error of replacing and swapping out parts to see what my issue was. I knew it was fuel related because I could let it cool down and it would work again.
I've never been in a m-tronic carb before, but I would imagine that there is still relatively the same with a needle valve and the lever that makes contact with the diaphragm inside. What is happening is because the lever is too high, when you shut it off in particular, because of the high pressure built up in the tank, the needle valve doesn't close completely and ends up flooding the engine. The lever should be (again m-tronic may be different but I don't think so) slightly below flush with the top of the gasket face. They make a special tool to gauge depth, but I always eyeball it. It doesn't take very much. Often the lever will work itself to be slightly above, and the no restart problem begins to occur. Hope this explains it better, and be sure to let me know if it fixes it.

 

[lone wolf]

OP, did you reset the computer like the owners manual describes? I think it is carry out 5 uniform cuts at full load. I would think this would happen anyway though?

 

[steven stern]

OP, did you reset the computer like the owners manual describes? I think it is carry out 5 uniform cuts at full load. I would think this would happen anyway though?

I have not tried that but will this evening

 

[lone wolf]

I have not tried that but will this evening

Well don't get your hopes up but try it. Gas fresh?

 

[blsnelling]

Try running the canned fuel as a test. It's much more resistant to heat issues.

 

[steven stern]

Try running the canned fuel as a test. It's much more resistant to heat issues.

I will try that. Thank you.

 

[steven stern]

Im going to try your guys ideas this evening after work and will let ya know how they work out

 

[Khntr85]

Damn I can only imagine how pissed off you were when it wouldn't restart....

How long have you had the saw???

If restarting it didn't help, I would probably take her back to dealer....can't get any work done or make money with a non-running saw!!

 

[steven stern]

Damn I can only imagine how pissed off you were when it wouldn't restart....

How long have you had the saw???

If restarting it didn't help, I would probably take her back to dealer....can't get any work done or make money with a non-running saw!!

It is a little over 2 years old, 2 months out of warranty of course. I have not got to try restarting it (im guessing that means the m tronic setup restart?)

 

[Khntr85]

It is a little over 2 years old, 2 months out of warranty of course. I have not got to try restarting it (im guessing that means the m tronic setup restart?)

Yes, I don't own a mtronic saw, so I can't tell you how to "re-start it"....I would look in manual, call dealer, or ask a trusted member here....I have seen people say many ways to do it, surely they only have one in the manual..

 

[lone wolf]

https://www.tapatalk.com/topic/16367-arboristsite-com/311901-stihl-261-running-problem-need-advice

 

[steven stern]

https://www.tapatalk.com/topic/16367-arboristsite-com/311901-stihl-261-running-problem-need-advice

?

 

[steven stern]

Well don't get your hopes up but try it. Gas fresh?

Yes fresh non ethanol with stihl ultra 2 cycle

 

[steven stern]

I went out and got a new spark plug and fuel filter. I did not get the canned fuel as it was 35$ a gallon yikes! As soon as im done typing this i will clean spark arrestor, and reset the saw. I will head up to the woods tomorrow morning and get back to you guys with the results. Thank you for all the advice i really appreciate it!!