261 M-Tronic - What makes it tick.....

[plcnut]

Does anyone with an M-Tronic saw also have an oscilloscope?
This would tell us if it is a PWM signal or merely a timed on-off, or another method of controlling the solenoid.
I have a scope I could put on one if I am able to find an M-Tronic saw...

 

[breese]

For those that use a modified Key on the flywheel, I have never done this and need an answer to something that might also help others that have tried to use the same method.

While you are not grinding on the Crank side of the key, when assembling with a modified / grounded key:
1-How do you know the flywheel is in the position you intend it to be when tightening the nut?
2-How do you know everything stayed in the position after tightening the nut?
2-Because of the intention of the key is to maintain the flywheels position in a Locked state, do you feel it is Possible that the flywheel can bounce from side to side on the flywheel there-by changing the timing from Normal to Advanced and back again multiple times with an acceleration or deceleration?

 

[paragonbuilder]

For those that use a modified Key on the flywheel, I have never done this and need an answer to something that might also help others that have tried to use the same method.

While you are not grinding on the Crank side of the key, when assembling with a modified / grounded key:
1-How do you know the flywheel is in the position you intend it to be when tightening the nut?
2-How do you know everything stayed in the position after tightening the nut?
2-Because of the intention of the key is to maintain the flywheels position in a Locked state, do you feel it is Possible that the flywheel can bounce from side to side on the flywheel there-by changing the timing from Normal to Advanced and back again multiple times with an acceleration or deceleration?

The key only aligns for assembly. The tapered shaft seats and is what holds the position. In fact if the flywheel is not tightened properly or there is debris preventing it from seating, the soft key will not hold the flywheel where it needs to be. It will shear.
As far as knowing if it stays where I intended, I mark it to see if it moves.

 

[MustangMike]

When you lock the piston in place and turn the flywheel before the nut is on, you know when it is against the filed side of the key. Sometimes, I insert a wire on the left of the flywheel cut just to ensure the gap is there.

As Dan says, friction holds the flywheel in place, not the key. If the flywheel can spin, it will easily shear the key.

I often clean the flywheel and crank tapered surfaces with Scotchbrite. It is imperative that the surfaces are clean and the nut is tight.

 

[breese]

I'm still just reading along. Thanks guys for this thread. Too many times these discussions end up in text messages or PMs. I appreciate this being in the open forum.

Work and communications continue on this project.
While some have sent me PM's, the work has expanded to multiple fronts.

At the current time (and not wanting to take away from the GTG's) there is a snag.
If anyone has a 261 or similar M-Tronic that needs work (but runs at idle) and not needing it, we could use such a saw to gather information from it.

There are a few theories at play but the cost of each effort has proven to be an issue.

If anyone has an idea or thought, I am open to it hearing it.
Thanks and as I understand more or know what is happening, I will be updating this thread.

 

[breese]

I have an idea but need some advise.
Is there a None M-Tronic saw that the coil and other parts would fit on?

I am thinking of getting a saw that has a bad piston and cylinder, removing the piston, mounting the M-Tronic devices and powering the saw with an electric motor at idle speed.

This would allow me to further investigate the electronics without the mess of gas, fumes, etc.

 

[paragonbuilder]

I have an idea but need some advise.
Is there a None M-Tronic saw that the coil and other parts would fit on?

I am thinking of getting a saw that has a bad piston and cylinder, removing the piston, mounting the M-Tronic devices and powering the saw with an electric motor at idle speed.

This would allow me to further investigate the electronics without the mess of gas, fumes, etc.

I like how you think! [emoji41]

 

[JMoney]

At that point would you really need more than a flywheel and a crank and maybe a bearing? Could probably mount it to a board to mount the coil, etc

 

[CR888]

The old edition 261 was standard carb with no MT, then they fitted MT to that exact saw. The new version II is offered in both MT & standard carb form. Interesting thread...

 

[MustangMike]

I really like my MMWS 261 C, just got done running another 3 tanks through it. Was the only saw I fired up today, it is very impressive. IMO, so much easier to have the M Tron version. Just think, you don't have to pull it again after it pops, it just runs!

 

[FergusonTO35]

I'm looking forward to seeing whether anybody other than Stihl or Husky comes out with computerized mixture control, or if they will just go straight to EFI when it becomes feasible.

 

[nohoff]

The MS 362 gets M-Tronic Vers. 2 soon.
They released a technical information for the dealers.
New cylinders/Coils and carb to get this saw more robust.
They have new Solenoids for dusty enviroments.

 

[VinceGU05]

I got a question. I have a stock 241 and my mate has a ported one. Both saws of not run for a week or more take 10 pulls to start +-1 pull. Every time. But the 661and 462 start with half as many pulls.
All saws once started are fine the rest of the day.

 

[nohoff]

Change the filter in the gas tank to 0000 350 3515
It's for M-Tronic machines which are difficult to start after some days without running.

 

[breese]

They released a technical information for the dealers.

Is there an English version of this Doc?

I'm looking forward to seeing whether anybody other than Stihl or Husky comes out with computerized mixture control, or if they will just go straight to EFI when it becomes feasible.

It is the Hope of this thread to come up with a method of being able to Better control the electronics'

Problem is $$ and or getting our hands on one.... Running or not.

 

[nohoff]

Sorry no english version. Its an information for the german dealers and helps to identify the differences. Most of the descriptions and reasons why they modify some parts are rubbish.
It says they changed the spark plug to M10 thread for more power and better standtime of the thread.
We also have a new IPL for the MS 362.

 

[paragonbuilder]

Is there an English version of this Doc?


It is the Hope of this thread to come up with a method of being able to Better control the electronics'

Problem is $$ and or getting our hands on one.... Running or not.

I just sold my 261 or I would have sent it to you for research.....

 

[breese]

I just sold my 261 or I would have sent it to you for research.....

If I can ask... How much did you get for it?

Everyone else reading... a non-running (headless) would work.
I am in the working stage of taking a saw and connecting an electric motor to spin it up.

 

[blsnelling]

How will you use one without a P&C? The rod will be flipping around beating up the case.

 

[breese]

How will you use one without a P&C? The rod will be flipping around beating up the case.

Turn it up-side-down? Maybe with a weight on it or bungee

I am sure I can come up with a way that would not damage a case...
Thought: Even possible to strip flywheel and M-Tronic.
Mount the flywheel on a shaft and make an adjustable mount for the Coil.

Like I said... Where there is a will, there is a way.