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ms261c M-Tronic problem today

MontanaResident

MontanaResident

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I fired up the saw and cut up the last of some log pieces I had. Shut off the saw, and sought out the neighbor to see about dropping a winter damaged tree. We rigged it up to ensure it was going to drop in a spot where we could easily cut it into 16" pieces. Saw started up fine, seemed to bog a little, but ran enough to drop the tree. About 20 minutes later we had dragged the fallen into an open area and began work. Well not me.

The ms261 was bogging something terrible. It felt like the saw wasn't warmed up. Trying to let it idle so it would warm up, it kept dying. It had plenty of gas, but I topped it off anyways. Still no joy. I took the cover off, everything looked okay. Took the air filter off, still everything looked okay. Removed the winter/summer block, because it was easy to do, and I was looking for possibly a loose impulse line. Nope everything looked good.

Cover off, air filter off, w/s block out, and it started up and ran fine. I put the block back and it ran fine, air filter on and it ran fine, cover on and it ran fine. 10 hours later, I still have no idea why it was bogging and would not idle more then a few seconds. I did, just a few hours ago started it up and it ran fine. There was a small minuet hesitation during one rev, but otherwise ran perfectly.

I should have pulled the plug, but it was working again before I got to the plug.

I'm really scratching my head on this one. It is still a brand new saw. Maybe 1 1/2 tanks of gas. Has been absolutely perfect before today. Any ideas?
 
MontanaResident

MontanaResident

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Hello, anybody?

I guess I am going to chalk this up as teething issues with a new saw. As of now we have another more intense cutting session this coming weekend. Will see if the issue is a one off, or something more persistent.
 
Motherboard

Motherboard

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Hello, anybody?

I guess I am going to chalk this up as teething issues with a new saw. As of now we have another more intense cutting session this coming weekend. Will see if the issue is a one off, or something more persistent.
Hopefully it will keep on going, the Mtronic probably finding its legs, make sure to let them run for 30 seconds
before shutting them off, otherwise all they will remember is running at full throttle, this will cause it to flood
during the next start up.
 
MontanaResident

MontanaResident

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Hopefully it will keep on going, the Mtronic probably finding its legs, make sure to let them run for 30 seconds
before shutting them off, otherwise all they will remember is running at full throttle, this will cause it to flood
during the next start up.

Thanks. Something plausible to try. I did forget to mention there was a brief whiff of flooding just prior to the problem. But flooding is not an issue for me, but with the M-Tronic it might be something to be aware of.
 
EchoRomeoCharlie

EchoRomeoCharlie

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The only real problem I have with Mtronic stuff is
1. Winter gas in warm weather
2. Shutting it off quickly after WOT
3. Running it out of fuel at WOT

1 & 2 are simple fixes...don't run winter gas in warm weather and let the saw come down to idle for a bit before shutting it off.

3 you have to kind of pay attention...as soon as you hear the bobble from low fuel, take it out of the cut, let it cool down for a bit, then shut it off and refuel. Don't just let it sing till it shuts off in the cut, it will almost always flood itself upon attempting to start up next time.

Flooding is simple to fix, pull the spark plug, pull the engine over several times with the plug out, reinstall plug, and start the saw.
 
MontanaResident

MontanaResident

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The only real problem I have with Mtronic stuff is
1. Winter gas in warm weather
2. Shutting it off quickly after WOT
3. Running it out of fuel at WOT

1 & 2 are simple fixes...don't run winter gas in warm weather and let the saw come down to idle for a bit before shutting it off.

3 you have to kind of pay attention...as soon as you hear the bobble from low fuel, take it out of the cut, let it cool down for a bit, then shut it off and refuel. Don't just let it sing till it shuts off in the cut, it will almost always flood itself upon attempting to start up next time.

Flooding is simple to fix, pull the spark plug, pull the engine over several times with the plug out, reinstall plug, and start the saw.

I'm pretty sure I got it solved. The problem is, and hopefully fixed, is the user/me going from yesterday's carb to today's m-tronics. The carb choke position is now the choke + high idle on the M-Tronics. I was going from choke straight to run without hesitation. Wrong. Let it idle for 15+ seconds in the choke position, or till it is fully warmed up. Even new I was having some bogging (albeit minor) because I was going to run position to fast.

I started it up this morning, no problems. Then hopped on the Can-Am and scouted for some firewood. When I got back, started it using the new method and understanding, and cut a wafer off a tree stump. Saw worked perfectly.

I'm satisfied. It was me, and not the saw. No warrantee trip to the dealer.
 
BradSt

BradSt

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I have personally found that some Mtronic saws like to have a warm restart with the master control switch in the triangle "start" position. Then when the engine starts, I blip the throttle within a second or so. If it dies, let it run in "start" position a bit longer. Don't be afraid to use the start position with a warm engine. It isn't just a choke, like a traditional setup.

As for idling before shutting off...I find a few seconds is generally enough, unless you're coming out of several long cuts, and the engine is hot. Then I idle longer for a cool down...same thing I do with my traditional carb saws. I haven't experienced the need for extended idle periods. I think the key is to not shut it off at high RPM...which most wouldn't do anyway.

I have 3 Mtronic saws, and they have all performed flawlessly.

EDIT: Posted at the same time as the OP's reply
 
MontanaResident

MontanaResident

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I have personally found that some Mtronic saws like to have a warm restart with the master control switch in the triangle "start" position. Then when the engine starts, I blip the throttle within a second or so. If it dies, let it run in "start" position a bit longer. Don't be afraid to use the start position with a warm engine. It isn't just a choke, like a traditional setup.

As for idling before shutting off...I find a few seconds is generally enough, unless you're coming out of several long cuts, and the engine is hot. Then I idle longer for a cool down...same thing I do with my traditional carb saws. I haven't experienced the need for extended idle periods. I think the key is to not shut it off at high RPM...which most wouldn't do anyway.

I have 3 Mtronic saws, and they have all performed flawlessly.

EDIT: Posted at the same time as the OP's reply

I agree. It is a different methodology then the carb saws. I think I have it all understood. Thanks!
 
MontanaResident

MontanaResident

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18" diameter?

24+. I drove by it the day before, but didn't look at it closely. The day of the drop, immediately I thought, I should have brought the longer bar. Still it fell where I wanted it to.

I used the ms880. I have learned the 880 is not a firewood saw. Built to run long bars, primarily. After that to be used as a poor mans mill. My 461 could have brought the tree down faster, and without all the crazy extra weight of the BIG saw.
 
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