Stihl MS 261 C-M

StarTech

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Remember this is a M-tronics controlled saw. Working on getting a troubleshooting guide when you don't have the diagnostic computer.
 

gmacmopar

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Ok I will try to do that with my drill. Do you know the size of socket I will need to put on my flywheel??
 

gmacmopar

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Where do I get a trouble shooting guide since I don't have a diagnostic computer??
 

gmacmopar

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Ok I'm confused, if this is a M-tronics controlled saw then I can't check the coil like most coils? I think I need some more help here.
 

StarTech

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This should help some. Most of the information is dealer only and all is copyrighted. I actually not suppose to have any of this info on hand. Just know a good source for the info.

But here is a few extracts. Please carefully all the instructions especially section 5.4.2. The following info should be available the owner of the saw in the first place under the right to repair.

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gmacmopar

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OK here's what I have done now! I bought a spark tester and hooked it up to the saw. I rechecked the gap on the flywheel with a feeler gauge and a business card and it is close to or even .10. Now got a socket on my drill made sure it was rotating the right way that the recoil goes. put the drill on low speed NO SPARK then I put it on high speed and I had SPARK!!! Wow!! put everything back together and tried starting it and it started. I let it run for a bit the took the brake off and ran it real hard for a while. Shut it off and tried to restart WON'T START. Put the tester back on and turned it over with the drill NO SPARK on low speed but I had SPARK on high speed. It still will not start!! So what do you think? I'm at a loss right now.

Thanks
 

gmacmopar

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Ok I let the saw cool down for 2 - 3 hrs went out to the garage checked for spark with the drill on high speed had spark. put the recoil back on choked the saw pushed the decompression button down and had the brake on. It fired on the 3rd pull and ran?? I let it run on idle for some time then took the brake off and ran it almost wide open for a good while. I shut the saw down and tried to restart not choking and it never fired out of 10 or so pulls. I pulled the plug and it looks like there are some very faint white spots on the electrode? Is this normal for a new plug? Think the carb is messed up and running to lean? I'm open for any suggestions at this point.
 

Fish

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Yeah most drills don't turn the newer coils fast enough. I didn't pursue it because you said that you were using the pull starter.
 

Fish

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Ok I let the saw cool down for 2 - 3 hrs went out to the garage checked for spark with the drill on high speed had spark. put the recoil back on choked the saw pushed the decompression button down and had the brake on. It fired on the 3rd pull and ran?? I let it run on idle for some time then took the brake off and ran it almost wide open for a good while. I shut the saw down and tried to restart not choking and it never fired out of 10 or so pulls. I pulled the plug and it looks like there are some very faint white spots on the electrode? Is this normal for a new plug? Think the carb is messed up and running to lean? I'm open for any suggestions at this point.
White spots? Sounds like your old mix had water in it and you finally got it out of your system.
 
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