Stihl ms261 piston question (burned)

[MartDalb]

This saw is driving me nuts.
Took out the spring in the coil, replaced it with another. The spark plug was not sitting tight in there at all.
Had Hoped that might have been the reason for the spark sometimes showing and sometimes not.
Did not help at all, sadly.

So... One last question remain.
Is this issue, with a spark, occasionally showing, but mostly not, and not enough to actually start the saw, caused by a defectice coil?

Lay it on me, yes or no.

 

[Crispexx]

This saw is driving me nuts.
Took out the spring in the coil, replaced it with another. The spark plug was not sitting tight in there at all.
Had Hoped that might have been the reason for the spark sometimes showing and sometimes not.
Did not help at all, sadly.

So... One last question remain.
Is this issue, with a spark, occasionally showing, but mostly not, and not enough to actually start the saw, caused by a defectice coil?

Lay it on me, yes or no.

I’m just a garage/YouTube mechanic, but seeing as you’ve replaced or checked everything else. It’s a big expensive piece that has a very low failure rate, but low isn’t 0. As long as the total price is less than a new saw I’d say its the next step.


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[MartDalb]

I’m just a garage/YouTube mechanic, but seeing as you’ve replaced or checked everything else. It’s a big expensive piece that has a very low failure rate, but low isn’t 0. As long as the total price is less than a new saw I’d say its the next step.


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Yeah. I checked out the price for a new coil + micro switch harness - will cost me something like 180$ - bare in mind I am from EU, where everything is more expensive.

If anyone has a used coil for sale, I will pay for it + shipping to Denmark Europe

 

[SteveSr]

Yeah. I checked out the price for a new coil + micro switch harness - will cost me something like 180$ - bare in mind I am from EU, where everything is more expensive.

If anyone has a used coil for sale, I will pay for it + shipping to Denmark Europe

Put the correct part number into Google or Fleabay. Anything sold as "used" on Fleabay is required to be fully functional or you get your money back.

I think that they are up to 3-M-tronic coil versions. I don't know about the interchangeability between versions. Post a legible photo of the model sticker on the handle and someone should be able to tell you which version M-tronic that you have.

Here is the harness:
https://www.ebay.com/itm/224266250997?hash=item34374f6af5:g:YjgAAOSw9Flfy~uQ

 

[Crispexx]

Any update?


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[MartDalb]

Any update?


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No not yet.
Started on some other projects.

I will update as soon as I hear from Stihl, been visiting their tech department and found some connections on the "inside".
But, not getting my hopes up, either way it has been a learning experience thus far

 

[SAWMIKAZE]

Mart, you might look at it this way. The Stihl dealer's mechanics told me It was a 10-hour job for them to rebuild a burned out 261 M-tronic. They wanted no part of it. It took me 12 hours after a 30-day wait for parts. Stihl was sold out of the slanted cylinder. The others do not fit and will not work. Say, if you get it done and it runs OK, Hooray! It's easier than an MS 441 M-tronic.

This took me about 2 hours and I'm an average saw mechanic on a good day.

 

[SAWMIKAZE]

No need to completely remove it. If you unhook the rubber support on the right hand side, there’s enough slack to get it off the carb studs and flop it over the left hand side

I wish I woulda done that....

Lesson learned.

 

[huskihl]

I wish I woulda done that....

Lesson learned.

Yep. Getting the spades or springs back in is a pita

 

[SAWMIKAZE]

Yep. Getting the spades or springs back in is a pita

It needed a bath anyway, I gave it the half assed air gun clean for 4 years. Other that keeping the air filter clean it didn't get enough love.

You were right though, after you do it, it goes pretty quick.

 

[MartDalb]

Not a real update, but.
I should have news sometimes next week, if everything goes as planned.
Thanks to everyone in the thread who helped out!

 

[MartDalb]

Update - Final one

So, she runs!
()
New coil, new micro switch+harness, new and notice GREEN solonoid (Stihl themselves said, black did NOT match this 261 model )
Anyhow...I could not be more happy!

Thanks to everyone for tips, tricks, help and time!

 

[Crispexx]

Green solenoid huh? Haven’t seen that one yet


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[MartDalb]

Green solenoid huh? Haven’t seen that one yet


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Yeah I don't know. But with the service Stihl provided me, I basically just said "okay" and did as they said.
Just for the record, Stihl has been EXTREMELY helpful here.

I will be out running her tommorow!

 

[SteveSr]

Yeah I don't know. But with the service Stihl provided me, I basically just said "okay" and did as they said.
Just for the record, Stihl has been EXTREMELY helpful here.

I will be out running her tommorow!

Now that it runs you can start back-substituting parts to fine the real culprit. This way you have known good spare parts for the next one...