Hello,
While searching the forum, I found a thread that seems interesting. On the 261 TC-M, problems also exist. It seems that the electronic system is well powered by 2 reverse polarized magnets on the flywheel. One of the 2 powers the coil that will generate the high voltage spark and the other is used for engine management and power supply of the CPU integrated into the coil. It is a real on-board computer that is in the coil. If you want to read all this, the thread is 15 pages long and it's very informative. For my problem, I still don't have an ignition and I'm thinking of heading towards the installation of a complete kit 1145 007 1802 that removes cough and comes back to having an MS 200 in my hands. What I want is a machine that always starts, and not a very sophisticated machine that is broken. My 020 T which at 26 years old, works perfectly and always starts immediately. I regret having bought this 201 TC-M.
As I continue to evaluate the 261 M-Tronic, I will update this posting with that information and pictures as they become available and I understand what it is.
I received a few coils and a carb from
@big t double. Thank you again..
Looking into the carb first, it appears this entire configuration talks thru what is known as a 1-Wire communication (getting access to the CPU will verify).
This 1-Wire allows for both asynchronous (bidirectional) data transfer and supplying power to the slaves (carb, etc) although this is somewhat limited but then again, we are talking chainsaws...
Here is an interesting paragraph
The entire system is charged by way of the flywheel.
This is a Magneto type system. The magnets on the flywheel transfer energy to the pickups on the coil pack (this is why the spacing between the coil and flywheel must be very close).
Next the energy is transferred to the larger of the 2 coils within the coil pack.
From the lager internal coil, the energy (voltage) passes thru (in simple terms) to the smaller coil and the voltage is raised high enough to fire a spark plug (somewhere between 5 and 10 thousand volts the last time I checked).
As the flywheel rotates, and the piston hit TDC, there is another pickup on the coil pack that when triggered allows the coil pack to now Fire the sparkplug.
By modifying the key between the flywheel and crank, you are moving the trigger point that the second pickup is seeing, there-by resulting in the advancement of timing you are seeing in your other modified saw builds.
The M-Tronic has the ability (internally) to Delay or Advance the firing of the sparkplug as it monitors the second pickup and logically deciding when to fire.
Now, because the coil pack is storing energy (voltage) created by the Magneto, the M-Tronic coil (internally) uses some of this power to supply power for the built in logic. This is not new. All single unit electronic ignitions have been using part of the power for internal logic. The M-Tronic is just using more of it to supply power to external sensors, coils, etc....
For my part, I continue my research. Have a good day
