Ms 201 m-tronic stalling issue

[drf256]

Saws idle different with timing advance. The 026, for example, will require a much richer L screw to idle correctly when it’s advanced.

This causes some extra fuel puddling in a model that’s already cursed by it. Interestingly, a different coil can solve the issue. It every well may be that the other coil has slightly different magnetism and thus timing.

It very well may be that the MT is unable to deal with the different running characteristics in the advanced saws. Turn it back and see what happens. Easy enough.

 

[NateSaw]

Black is what Stihl lists for the 201. Considering they’re almost always the ones that fail, I usually replace with white or green, but black should be fine. Have you swapped carbs from the ported saw to the non?

Negative. But I have replaced the carb on the non.

 

[NateSaw]

Saws idle different with timing advance. The 026, for example, will require a much richer L screw to idle correctly when it’s advanced.

This causes some extra fuel puddling in a model that’s already cursed by it. Interestingly, a different coil can solve the issue. It every well may be that the other coil has slightly different magnetism and thus timing.

It very well may be that the MT is unable to deal with the different running characteristics in the advanced saws. Turn it back and see what happens. Easy enough.

I'll get em hostage next week and do just that. That's where my guts have been bubblin. Coil/timing. Yeah that good Ole 026... I've become quick with the pocket driver on the L with that girl. I have a behind the chipper fire up and make quick cuts setting, and a buck it up in long repeated cuts setting...

 

[David Young]

I went to far on TA on a 201 it did what you are saying, backed it off a little and the problem went away. The one I was working on was brand new so it took out a lot of the other variables.

 

[Mastermind]

I went to far on TA on a 201 it did what you are saying, backed it off a little and the problem went away. The one I was working on was brand new so it took out a lot of the other variables.

I advance the flywheel on the non-mtronic 201, but not on the mt version.

 

[David Young]

I advance the flywheel on the non-mtronic 201, but not on the mt version.

I do these for a tree company, mm ta and I do some work on the intake. I haven't tried not doing the TA on the Mtronic. one thing I liked was the Mtronic seems to sort out the idle and acceleration which I found finicky on the older screw carbs.

 

[Ketchup]

I advance the flywheel on the non-mtronic 201, but not on the mt version.

Same. The Original MT 201 seems to tolerate a small advance but the new ones don’t like it.

 

[NateSaw]

I went to far on TA on a 201 it did what you are saying, backed it off a little and the problem went away. The one I was working on was brand new so it took out a lot of the other variables.

Nice to hear from you David! I look forward to fireside chats, hopefully at @Duane(Pa) gtg! I confiscated the problem saw. Tommorow I'll roll it back a bit. Perhaps just to stock timing to rule it out completely. Then I'll creep forward. Thanks for your input!

 

[NateSaw]

Same. The Original MT 201 seems to tolerate a small advance but the new ones don’t like it.

Our climber didn't seem to notice a difference anyway. I wonder... Can m-tronic compensate? Perhaps it's pulling it back hard enough to stall it. In the car world, late timing dips the idle. I still don't know enough about m-tronic capabilities. I'm learning they really do adapt more and more everytime you run them. The ported 661 kept it's original rings, as it's a newer, lower hour saw. Yet, it almost acts like a saw seating in... Keeps getting better.

 

[Mastermind]

Our climber didn't seem to notice a difference anyway. I wonder... Can m-tronic compensate? Perhaps it's pulling it back hard enough to stall it. In the car world, late timing dips the idle. I still don't know enough about m-tronic capabilities. I'm learning they really do adapt more and more everytime you run them. The ported 661 kept it's original rings, as it's a newer, lower hour saw. Yet, it almost acts like a saw seating in... Keeps getting better.

Most m-tronic saws have no problem with timing advance. The 201TC doesn't seem to do well advanced....at least not with the same amount as we usually do. I believe that when Stihl created the TC they changed the ignition timing, because before it came out, the 201 needed to be advanced.

 

[NateSaw]

Most m-tronic saws have no problem with timing advance. The 201TC doesn't seem to do well advanced....at least not with the same amount as we usually do. I believe that when Stihl created the TC they changed the ignition timing, because before it came out, the 201 needed to be advanced.

Solid info Randy I still haven't had a chance to get to that saw. Tommorow. I hope bubbas healing well!

 

[mtndragon]

I've been lurking in this thread to try to learn the best way to eek out a little more performance out of my newish 201TC (last summer). Was considering a timing advance and muffler mod, but seems like a timing advance on a newer 201 Mtronic is not a great idea. Since picking up a 2511 and putting on a straight pipe, the 201 has not seen a lot of use climbing, as it's kinda a boat anchor and when the 2511 can't cut it, I have a 261 sent up. My 201 is now a throw in the truck saw to just have down on my buddy's ranch, which means cutting a bit of already down, smaller oak.

So, for that purpose, just a muffler mod and maybe a switch over to speedcut nano?

Not trying to hijack, but with Mastermind and Ketchup following this thread, I thought I'd ask the question....

 

[Mastermind]

I've been lurking in this thread to try to learn the best way to eek out a little more performance out of my newish 201TC (last summer). Was considering a timing advance and muffler mod, but seems like a timing advance on a newer 201 Mtronic is not a great idea. Since picking up a 2511 and putting on a straight pipe, the 201 has not seen a lot of use climbing, as it's kinda a boat anchor and when the 2511 can't cut it, I have a 261 sent up. My 201 is now a throw in the truck saw to just have down on my buddy's ranch, which means cutting a bit of already down, smaller oak.

So, for that purpose, just a muffler mod and maybe a switch over to speedcut nano?

Not trying to hijack, but with Mastermind and Ketchup following this thread, I thought I'd ask the question....

The biggest problem with the 201 in terms of performance is the inserts that are epoxied in on the sides of the jug. They fit horribly, and need quite a lot of work in the upper transfer ports to make them less restrictive. Of course, a muffler mod can't hurt.....

 

[Ketchup]

There’s not tons of easy improvements on the new 201t. I learned from Randy that the biggest improvement is smoothing out the transfer uppers. That requires a right angle handpiece. But the muffler mod will help. I like to hog out the original outlet hole with a sphere burr instead of drilling a hole in the side (saves the already fragile plastics). I put a second hole on the far right side, under the deflector but that bypasses the screen so it’s not for everyone.
I like the speedcut for a 16” bar. 14” or smaller it’s not different enough to matter.

 

[mtndragon]

Thank you both for your responses. I am glad I held off on the timing. I have been running a 16" bar and was planning on the same for the Speedcut. I am going to keep it simple and just go with the muffler mod and 16" speedcut. I appreciate your insights. Now back to NateSaw's slightly buggered 201...

 

[David Young]

Our climber didn't seem to notice a difference anyway. I wonder... Can m-tronic compensate? Perhaps it's pulling it back hard enough to stall it. In the car world, late timing dips the idle. I still don't know enough about m-tronic capabilities. I'm learning they really do adapt more and more everytime you run them. The ported 661 kept it's original rings, as it's a newer, lower hour saw. Yet, it almost acts like a saw seating in... Keeps getting better.

This may be too deep in the weeds but....

advancing the ignition timing you are maximizing the power stroke depending on the propagation of the flame front. IF you go slightly too far on your ignition timing you can compensate by adjusting the Carb to a rich condition. The fuel rich mixture will slow the flame front and get you back in the ball park but is not truly optimized. when you go under load the tune will clear up but will not be as good as if you have the timing and mixture tuned right. you are just covering a mistake. I believe Mtronic can provide enough fuel to mask an over advanced situation.

 

[David Young]

There’s not tons of easy improvements on the new 201t. I learned from Randy that the biggest improvement is smoothing out the transfer uppers. That requires a right angle handpiece. But the muffler mod will help. I like to hog out the original outlet hole with a sphere burr instead of drilling a hole in the side (saves the already fragile plastics). I put a second hole on the far right side, under the deflector but that bypasses the screen so it’s not for everyone.
I like the speedcut for a 16” bar. 14” or smaller it’s not different enough to matter.

do you have pictures?
@Mastermind
@Ketchup

 

[Mastermind]

do you have pictures?
@Mastermind
@Ketchup

I do not.

 

[David Young]

I think you mean I donut

I donut as well.... Boston cream please

 

[Ketchup]

I like powdered cake donuts with coffee. I think there’s a few in the ported cylinder artwork thread. Somewhere between page 3 and 144.