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Stihl ms261 piston question (burned)

MartDalb

MartDalb

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If the flywheel actually rubbed that flywheel, the magnets could be bad. Coil could be fine.
Yeah I am worried, slightly about that.

Talked to a Guy, owns a big stihl shop. Word is he knows ups and downs etc.
He more or less said, its a 1% chance that it is the coil. Based on how many times he has seen issues being coil related.
He also said, he had no used ones, and a new coil is around 150-160$.
Which I aint spending on this project.

So.
I Will put back the coil
Check out the solonoid
And retest in a very dark room, perhaps the spark is so small I am missing it?
 
MartDalb

MartDalb

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If the flywheel actually rubbed that flywheel, the magnets could be bad. Coil could be fine.

So, how much damage would a flywheel need to take before it won't work?
This one does have 1 line with a noticable scratch into it, not deep, but I can feel it. (and If you read above in the post, I did mention early on, that the coil seemed to sit too close to the flywheel, which made me adjust it)

I ran an old jonsered once, which had a lose (I didn't know) coil, it ran, 30seconds and then split the coil end into pieces.
The flywheel worked perfectly fine, after a new coil was put on.

Just wondering, before I start looking high and low for a coil and or spend cash on other parts.
 
drf255

drf255

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No answer for certain. I never believed it to be possible until i had it happen.

If you have a magnet, you can try to test it.

The magnets are labeled N/S on flywheel. Make sure that the magnets sitting next to each other are different polarities. They have to be for the coil to charge and sense. A hit can change them.
 
MartDalb

MartDalb

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Funny thing here.

Called up 4 different Stihl dealers, spoke to their "head mechanic" each place.

No one has any used parts, at all.
No one had ever heard or dealt with any solonoid issues on the ms261C
No one wanted to belive it was the coil, but had no other idea as to why or how it would not spark.
 
Crispexx

Crispexx

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Funny thing here.

Called up 4 different Stihl dealers, spoke to their "head mechanic" each place.

No one has any used parts, at all.
No one had ever heard or dealt with any solonoid issues on the ms261C
No one wanted to belive it was the coil, but had no other idea as to why or how it would not spark.

Do you have the repair bulletins for this saw as well? I have three I can send you if needed. Might help


Sent from my iPhone using Tapatalk
 

MartDalb

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Minor update.
Got the solonoid off. Was not dirty, neither was the inside of the carb.

Will consider that new coil... Even though it is stupid expensive.
Trying to get a dealer to let me test one, and be able to return if its not the coil.
 

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huskihl

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Minor update.
Got the solonoid off. Was not dirty, neither was the inside of the carb.

Will consider that new coil... Even though it is stupid expensive.
Trying to get a dealer to let me test one, and be able to return if its not the coil.
I’d replace that solenoid with the updated white one. Black ones have had issues for me
 

MartDalb

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Update - and some help is needed.

Was it said, that if solonoid and/or carburator does not get power, there will be no spark? @SteveSr

Toying around the wires, harness etc.
Why not...right?

I was measuring the carburator "red wire" from coil end to carb end.
I had continuity between the end part of the harness and the coil end. Which I was wondering about.
It should have a clear signal from end to end here, right?

Now, I am, by no means, at all, good at electric stuff, but this can't be right.

I will try posting pictures.
(not actually sure if that "metal thingy" should be touching the "green" spring. Any advice?
 

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MartDalb

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impossible to describe, I tried...No idea if what I posted makes sense, or if It will change anything.
Time will tell!

Any feedback is welcome....why the heck does Stihl not cover this in their service manual! :rolleyes:

When the metal thingy, from the red wire does not touch the spring, I get this reading.
When it touches, I get 0.00 read.
 

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MartDalb

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I suspect that there is a separate manual that covers troubleshooting of the M-tronic system. Do you have the SM that covers the "-CM" variant?
I do not, no.

But I will say, something might be up in this part of the wires/harness.
I was getting no read and now I am getting 2 seperate reads, on the carb ends sticking out.
No resistance on the red end, and 0.03 on the green. Which would make sense, since it has a resistor placed on it?
Anyone with electric knowledge, please enlighten me :bowdown:
 

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MartDalb

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Update

We got spark, atleast, sometimes. And mostly when I pull the damn robe REALLY hard!
Now, I can't damn well test if it will start, because I took off too much coil wire when reattaching the spring etc.

So, I will have to wait a few days for wire to arrive!
Atleast some good news, seeing spark...not sure if it runs, but ...a spark is a spark! :cheers:
 
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