Stihl 261 C-M Intermittent Hot Start Issue

[Knobby57]

You are asking way to much out of that little saw to slab even pine . A rough cutting chain will throw off the m tronic . I found that out on a grabby chain on my 441cm . Even that said you are asking way too much from 261. You are probably heating that bugger up pretty good . Do yourself a favor and get a bigger saw to mill with and you won't kill a great saw like a 261


Sent from my phone when I should be working

 

[ReinkeFand&S]

Has there been any resolve on this. I am having the very same issue. I have now been to the dealership three times, they have put on a new carb and still will not start after using the it.

 

[MOD]

Nope. Mine went in for a new solenoid, then a whole new carburetor, and it still floods if you look at it funny. It can be somewhat managed, though.

After mine went in for a new carb, they said they ran it for 30 minutes and then it started up fine. Thing is, when I opened it up to change the chain, I noticed the whole area was full of bar oil gunk, but no sawdust. So they ran it for 30 minutes, but didn't put any load on it. The next day I bucked a bradford pear branch, about 10" dia, that had fallen in a friend of a friend's yard. It cut like butter, but even after that very very light task, it had to sit 20 min. to start up again. Tried different bars, multiple chains...behavior is consistent. Any load at all and it floods shortly after turning it off.

I called the dealer and said I wanted a new saw. They said no (they tested it as working fine, after all), so I've mostly had to live with it. Needless to say, never buying another m-tronic anything. Best I can figure, there is something unrelated to the carburetor that is susceptible to manufacturing sample variation (not all saws exhibit this behavior), that continues to dump fuel into the engine after turning it off.

my tips:
-Never more than three pulls in choke, even when cold.
-Always start in run if warm
-To shutoff, run full throttle for ~5 sec, then hit the shutoff while running it full throttle. Seems to leave the engine drier, but could be in my head.
-Keep wrench handy and pull the spark plug if it doesn't start in 5 pulls.

It's frustrating as hell and I can't believe I paid $600 for this POS.

 

[ReinkeFand&S]

After the fourth trip to the dealer yesterday and a call to Stihl warranty, and a little heated debate, I'm going to pick up a new power head this morning after getting out of the tree stand. I guess I'm lucky to have great dealer, but when you have bought 5 saws and a SCAG mower from him he treats me pretty well, even if I'm one of the younger guys he sees.

 

[Bkknnk]

I have the same issue with the 261c that was purchased about 2 months ago. Starts fine when cold, but starting when the saw is hot is impossible! Dealer said gas was bad...wasn't the gas, as next day started fine with same gas. I haven't read all the replies, but should I return this frustration of a saw!?

 

[MustangMike]

You are suppose to let a M-Tronic saw idle for a bit before shutting them off (not at full throttle).

If warm, always try run position before start position.

If it still does not start, pin the throttle and give it a few pulls, and I'll bet it will start.

 

[MelMalinowski]

I bought a Stihl 261 C-M in July 2019 from a very knowledgeable servicing dealer in WA. With about 10 hours on it, it began displaying symptoms very much like posted by Bl8tant. Once hot, would not start. Sometimes, it would be running and just stop, then not start. Dealer serviced, the computer said it was OK. Took it out, fresh fuel filter, spark plug, Stihl gas and oil, fell one 18" tree, and at the start of the next undercut, it stopped and would not start. Dealer is scratching his head, and will escalate on Monday. In the meantime, my job is being held up. This will be a test of Stihl corporate customer service. I hope they won't keep servicing it and sending it out without testing the hot performance. If I were Stihl, after two tries I'd give the guy a new saw and take the problem child in for testing under stress to figure out why occasional saws of this model can do this. It sounds like an ignition component that fails intermittently when hot. Anyway, I'll report how it goes here. 70° weather, a pro saw should start and run easily and consistently.

 

[holeycow]

 

[MelMalinowski]

I bought a Stihl 261 C-M in July 2019 from a very knowledgeable servicing dealer in WA. With about 10 hours on it, it began displaying symptoms very much like posted by Bl8tant. Once hot, would not start. Sometimes, it would be running and just stop, then not start. Dealer serviced, the computer said it was OK. Took it out, fresh fuel filter, spark plug, Stihl gas and oil, fell one 18" tree, and at the start of the next undercut, it stopped and would not start. Dealer is scratching his head, and will escalate on Monday. In the meantime, my job is being held up. This will be a test of Stihl corporate customer service. I hope they won't keep servicing it and sending it out without testing the hot performance. If I were Stihl, after two tries I'd give the guy a new saw and take the problem child in for testing under stress to figure out why occasional saws of this model can do this. It sounds like an ignition component that fails intermittently when hot. Anyway, I'll report how it goes here. 70° weather, a pro saw should start and run easily and consistently.

Outcome: First business day after problem, Stihl Northwest requested that my 261 CM be sent in for testing, and authorized giving me a new 261CM. Before quitting time, I fell 14 12-18" Douglas Fir with it, and it performed flawlessly. Kudos to Thomas Building Center and Stihl. I'll stress test it more on this project and report. Dealer says that the 261CM has enough power for a 20" bar, and that if it is performing normally, heat is not an issue. It cuts well for a 50cc relatively lightweight saw. The design and quality of build of the pro series saws is impressive. A pro 'topper' was in the shop and recommended using Aviation 100 octane ethanol-free gas, so I'm buying that at our local airfield. Stihl recommends using their special chain oil that is sticky enough to make it around to the bottom of the bar even at the very high chain speeds that the pro saws operate at. Could be true.

 

[oldfortyfive]

I got my 261CM last summer and have not seen any of these issues. It's been a great saw.

 

[MountainHigh]

My 261 c-m will only start by giving it a real hard snap drop saw pull.

Just using a medium pull technique that has worked on every other saw I've owned, fails to start this saw.

Taking it back to the shop... again

 

[qluk]

Found this thread because I've got the same problem on my 261 C-M. I'm a home user and also have a 193T and 150 TC-E. Those 2 work great. Stihl oil mix bottle stated to use 89 octane so I bought fresh gas today. I ran the motor on and off for about 30 minutes. It was starting up fine each time, and the motor was only off for less than a minute each time. Then I re-filled the tank and after about 15 minutes of it sitting there I tried to get back to work - put it in the run position and it wouldn't start; put it in the half-choke position (whatever you call that at 3 positions down) and it started full throttle for about 2 seconds and never started again. Now is 6 hours later and it still won't start. I assumed flooding but when I removed the spark plug and tried to empty anything out of the cylinder, nothing came out. About a week ago I followed the re-calibration process in the manual.

The chainsaw is about 1 1/2 years old and I probably have 7 hours of use over that time on it. I have always had this problem with the saw and each time toss it aside and get the 193T to continue. It tends to start up the next day (a cycle of moon gravity?).

I'll update if I make any progress. I bought this chainsaw because the 193T works so well, so my first thought is M-tronic. Let's see what Stihl says tomorrow.

With all that said, looking at the attached image of the switch which doesn't match the manual, is it an older model or something?

 

[MountainHigh]

Found this thread because I've got the same problem on my 261 C-M. I'm a home user and also have a 193T and 150 TC-E. Those 2 work great. Stihl oil mix bottle stated to use 89 octane so I bought fresh gas today. I ran the motor on and off for about 30 minutes. It was starting up fine each time, and the motor was only off for less than a minute each time. Then I re-filled the tank and after about 15 minutes of it sitting there I tried to get back to work - put it in the run position and it wouldn't start; put it in the half-choke position (whatever you call that at 3 positions down) and it started full throttle for about 2 seconds and never started again. Now is 6 hours later and it still won't start. I assumed flooding but when I removed the spark plug and tried to empty anything out of the cylinder, nothing came out. About a week ago I followed the re-calibration process in the manual.

The chainsaw is about 1 1/2 years old and I probably have 7 hours of use over that time on it. I have always had this problem with the saw and each time toss it aside and get the 193T to continue. It tends to start up the next day (a cycle of moon gravity?).

I'll update if I make any progress. I bought this chainsaw because the 193T works so well, so my first thought is M-tronic. Let's see what Stihl says tomorrow.

Sorry to hear you're having saw problems. Here's another thread about my saw that *might contain some help for yours:

https://www.arboristsite.com/community/threads/261-c-m-running-lean.336664/

 

[farmer steve]

Found this thread because I've got the same problem on my 261 C-M. I'm a home user and also have a 193T and 150 TC-E. Those 2 work great. Stihl oil mix bottle stated to use 89 octane so I bought fresh gas today. I ran the motor on and off for about 30 minutes. It was starting up fine each time, and the motor was only off for less than a minute each time. Then I re-filled the tank and after about 15 minutes of it sitting there I tried to get back to work - put it in the run position and it wouldn't start; put it in the half-choke position (whatever you call that at 3 positions down) and it started full throttle for about 2 seconds and never started again. Now is 6 hours later and it still won't start. I assumed flooding but when I removed the spark plug and tried to empty anything out of the cylinder, nothing came out. About a week ago I followed the re-calibration process in the manual.

The chainsaw is about 1 1/2 years old and I probably have 7 hours of use over that time on it. I have always had this problem with the saw and each time toss it aside and get the 193T to continue. It tends to start up the next day (a cycle of moon gravity?).

I'll update if I make any progress. I bought this chainsaw because the 193T works so well, so my first thought is M-tronic. Let's see what Stihl says tomorrow.

With all that said, looking at the attached image of the switch which doesn't match the manual, is it an older model or something?

Yes,older model. Mfg date should be on the sticker on the handle. My new one only has stop,run and choke postions.

 

[Be Stihl]

Found this thread because I've got the same problem on my 261 C-M. I'm a home user and also have a 193T and 150 TC-E. Those 2 work great. Stihl oil mix bottle stated to use 89 octane so I bought fresh gas today. I ran the motor on and off for about 30 minutes. It was starting up fine each time, and the motor was only off for less than a minute each time. Then I re-filled the tank and after about 15 minutes of it sitting there I tried to get back to work - put it in the run position and it wouldn't start; put it in the half-choke position (whatever you call that at 3 positions down) and it started full throttle for about 2 seconds and never started again. Now is 6 hours later and it still won't start. I assumed flooding but when I removed the spark plug and tried to empty anything out of the cylinder, nothing came out. About a week ago I followed the re-calibration process in the manual.

The chainsaw is about 1 1/2 years old and I probably have 7 hours of use over that time on it. I have always had this problem with the saw and each time toss it aside and get the 193T to continue. It tends to start up the next day (a cycle of moon gravity?).

I'll update if I make any progress. I bought this chainsaw because the 193T works so well, so my first thought is M-tronic. Let's see what Stihl says tomorrow.

With all that said, looking at the attached image of the switch which doesn't match the manual, is it an older model or something?

Mine only has the three positions also, no half choke. What does the clutch cover look like, does it look like the new 462 or is it the more common larger cover?


Sent from my iPhone using Tapatalk

 

[qluk]

Following up on my issue in case someone down the line ends up with a similar problem and reads my original post. I gave it to a dealer who adjusted the carb and installed a new fuel line and filter. It ran for all of 10 minutes, died, and was incapable of starting. Thankfully Stihl is open for calls on Saturdays. I got a rep on the line and the person was familiar with the condition and said the control unit, part number 1141 400 4702, is causing it. They warrantied the part and it's at the dealer now waiting for the part to arrive.

 

[AJL]

Following up on my issue in case someone down the line ends up with a similar problem and reads my original post. I gave it to a dealer who adjusted the carb and installed a new fuel line and filter. It ran for all of 10 minutes, died, and was incapable of starting. Thankfully Stihl is open for calls on Saturdays. I got a rep on the line and the person was familiar with the condition and said the control unit, part number 1141 400 4702, is causing it. They warrantied the part and it's at the dealer now waiting for the part to arrive.

Did you get it to work flawlessly after the control-unit was changed?
I have the same hot-start issue...

 

[AJL]

Following up on my issue in case someone down the line ends up with a similar problem and reads my original post. I gave it to a dealer who adjusted the carb and installed a new fuel line and filter. It ran for all of 10 minutes, died, and was incapable of starting. Thankfully Stihl is open for calls on Saturdays. I got a rep on the line and the person was familiar with the condition and said the control unit, part number 1141 400 4702, is causing it. They warrantied the part and it's at the dealer now waiting for the part to arrive.

Did you get it to work flawlessly after the control-unit was changed?
I have the same hot-start issue...

 

[bigbadbob]

Following up on my issue in case someone down the line ends up with a similar problem and reads my original post. I gave it to a dealer who adjusted the carb and installed a new fuel line and filter. It ran for all of 10 minutes, died, and was incapable of starting. Thankfully Stihl is open for calls on Saturdays. I got a rep on the line and the person was familiar with the condition and said the control unit, part number 1141 400 4702, is causing it. They warrantied the part and it's at the dealer now waiting for the part to arrive.

Did you get it to work flawlessly after the control-unit was changed?
I have the same hot-start issue...

Did it get fixed?? I have same issue,,

 

[EchoRomeoCharlie]

I know this is an old thread but here's my experience:

I ran into hot start issues with my 261c they were all solved by how I use the saw.

1. Don't shut the saw off immediately after running at WOT in a cut. Let the saw idle for a minute before shutting it off. This one right here solved 98% of my issues with hot start. Since this has become my SOP, I've not had a hard time with hot starts since.
2. Don't use winter gas in the summer. Yes, it's a thing, yes it causes problems with hot starting. Look in the tank when you're having a hot start issue and most likely you will see bubbles coming out of the fuel filter. That's called vapor lock brother.
3. Don't run the saw out of fuel. As soon as you hear a low fuel burble...shut it down and refuel. It does not like running out of fuel in a cut, it will be hard to restart.