Stihl MS-441 C-M Dies After Idling

[MtnMike]

Need your expert opinions and experiences with the MS-441 CM and its idling behavior.

Here's my problem. After bringing down a few trees and doing a bit of limbing and bucking, I'll set my saw down and let it idle while I move a little debris out of my way...usually around 20-30 seconds. As soon as I grab it and pick it up off the ground she'll stumble and die every time. It starts right up again and runs fine, but if I set it down, and let it idle for 20-30 seconds, as soon as I grab it and pick it up...it dies again. This happens nearly every time I set the saw down.

I took it to one dealer who said they couldn't recreate the problem. I took it to another dealer who thought the "metering diaphragm was a little stiff." The Stihl head office in Denver gave the shop to go-ahead to replace the entire carb, which they did.

I got a chance to take out a medium-sized honey locust tree the other day, and sure enough, every time I set the saw down, idled it, and picked it up again, it died.

Seems to happen regardless of the saw temperature, but slightly more common when the saw is warmed up. And the saw has done this since it was new.

A fellow at the Stihl head office in Denver sent me the M-Tronic carb reset procedure and asked that I try it in the field to see if it made any difference. I performed the routine as described, and it made no difference at all. Still dies when you pick it up.

Here's a video of the behavior:

Conditions: ~35-degrees, elevation ~7800', TruFuel 50:1.

So, the questions:

1. M-Tronic owners: Have you seen your saw do this? Does your saw hold a nice sturdy idle all the time?
2. Anybody have any idea what's going on and how to fix it?

Intermountain Stihl in Denver has been really great to work with, and they said to send it down to them if it keeps exhibiting this behavior, which I plan to do in the next week or so, but in the meantime I thought I'd poll you guys and see what you thought.

Any insights are appreciated.

Thanks in advance.

 

[nmurph]

Well, it's dumping too much fuel into the carb...that's the duh part. Why??? I don't have a clue. I think this is the first problem I have seen with the M-tronic carbs. It sounds like the distro is being good about helping you out!!!!

 

[naturelover]

Pulling or pinching something when picking it up?

Maybe try flexing the handles a bit while on the ground? Wonder if you'd bring it off idle before picking it up?

Another thing that popped into my head was its overcompensating for an air leak?

(On phone and can't see video...)


Sent from my iPhone 5 using Tapatalk

 

[CR500]

did you re-calibrate the new carb?

 

[MtnMike]

Hey Guys,

Thanks for the quick replies. Some things to think about there: Air leak and/or fuel dump. I'll hang on to that for the next time I talk to the distributor. Who, indeed, has been really helpful so far.

I'll try "torquing" the chassis while it's on the ground and see what happens, but I really don't *think* it's a "mechanical" issue. At least not "mechanical" in the sense that I'm pinching a fuel line or shorting the spark plug.

I did re-calibrate the new carb. No change.

CR500: You have the same saw (except for the Snellerizing), I presume yours idled nice and steady before being Snellerized? That's what I'd like to get: Some feedback from other 441CM owners on their saw's idling behavior.

 

[Stihlman441]

Need your expert opinions and experiences with the MS-441 CM and its idling behavior.

Here's my problem. After bringing down a few trees and doing a bit of limbing and bucking, I'll set my saw down and let it idle while I move a little debris out of my way...usually around 20-30 seconds. As soon as I grab it and pick it up off the ground she'll stumble and die every time. It starts right up again and runs fine, but if I set it down, and let it idle for 20-30 seconds, as soon as I grab it and pick it up...it dies again. This happens nearly every time I set the saw down.

I took it to one dealer who said they couldn't recreate the problem. I took it to another dealer who thought the "metering diaphragm was a little stiff." The Stihl head office in Denver gave the shop to go-ahead to replace the entire carb, which they did.

I got a chance to take out a medium-sized honey locust tree the other day, and sure enough, every time I set the saw down, idled it, and picked it up again, it died.

Seems to happen regardless of the saw temperature, but slightly more common when the saw is warmed up. And the saw has done this since it was new.

A fellow at the Stihl head office in Denver sent me the M-Tronic carb reset procedure and asked that I try it in the field to see if it made any difference. I performed the routine as described, and it made no difference at all. Still dies when you pick it up.

Here's a video of the behavior:

Conditions: ~35-degrees, elevation ~7800', TruFuel 50:1.

So, the questions:

1. M-Tronic owners: Have you seen your saw do this? Does your saw hold a nice sturdy idle all the time?
2. Anybody have any idea what's going on and how to fix it?

Intermountain Stihl in Denver has been really great to work with, and they said to send it down to them if it keeps exhibiting this behavior, which I plan to do in the next week or so, but in the meantime I thought I'd poll you guys and see what you thought.

Any insights are appreciated.

Thanks in advance.

Yes i did have to same problem with one of mine,i sent it back to Brad Snelling and he fixed it,contact him.

 

[Andyshine77]

I believe Brad lowered the carb metering lever, seemed to work fine after that. Does the saw hesitate when it idles for 10 seconds or so?

 

[imagineero]

One of mine does the same, the other two are fine. There's a technique for dealing with it, but it's kinda tricky. First, walk towards the saw, but then, make out like you just noticed your shoe lace is undone. Be sure and do this within arms reach of the saw or you're wasting your time. Bend over and start fussing with your laces, then make a quick lunge for the saw and get on the throttle real fast before picking the saw up. You've got to be quick with it or the saw works out what's going on.

Shaun

 

[memory]

I have the 441RCM version, pretty much the same as yours but with the larger dawgs, HO oiler, stiffer springs and full wrap handle. Anyways, mine does not die when idling for a few seconds but it does come real close. I normally don't let mine idle that long but I will let it idle for a few seconds and I do notice a change in rpm's when I pick it up, it acts like it wants to die. I don't think it ever has. Even when carrying the saw while it is idling, when I bring it back up, there is a change. Now that you bring this issue up with yours, I will look into it more closely. I never really gave it much thought.

My saw is less than a year old.

 

[Swamp Yankee]

Not much help but,

My MS441C-M was purchased when they first came out guessing close to a couple years ago. No issues idling, accelerating, or cutting at rpm. It has been rock solid reliable as any saw I've ever owned. After watching your video however, at idle my saw does not sound at all like yours. Mine has a much smoother idle almost no change in pitch or speed, whether being held, sitting on the ground, or even laying on its side there is no difference. Yours seems to be adjusting frequently, or at least sounds that way to me. Completely different from mine.

It's good that Stihl wants to work with you to resolve the issue. I know from experience how frustrating it can be to have issues with a saw and have the dealer and manufacturer tell you to go away and pound sand.

Some info that may help the saw gurus diagnose the problem. How long ago did you buy the saw? Any idea how many hours are on it? Was this a problem from day one, or a more recent development?

Wish you the best, hope all is resolved to your satisfaction.

Take Care

 

[CR500]

I actually had my saw sent back to Brad for a pop-up piston and I believe that he did lower the metering lever just a fuzz. Before that though it would idle fine but lets say 10 mins of idling it would load up and be really rich until it cleared out.

 

[FLRA_Dave]

I got my MS441R C-M in October. It had died on me once while I was picking it up off the ground. I can usually count on it sounding like it wants to die when I pick out up off the ground when It is idling for more than a few seconds. Glad to hear that I wasn't the only one this happens to.

 

[AKDoug]

Mine never gets set down to idle that long. I'll have to play with it tomorrow.

 

[stihl for life]

have any of you guys changed your mix in gas? say u run 50-1 try mixing a tank at 40-1 or 32-1 and see if that runs any better or if u are running at say 32-1 try running 40-1 or 50-1.

 

[confused8122]

My 441 rcm was new last may. Has about 9-10 gallons of fuel through it. From day 1 it has had an odd stalling problem. It is not as frequent now as it was when new. Randomly at idle it stalls, sounds just like someone turned it off. Has happened while idling in my hand, but mostly when I set it down and turn my back for a moment or 2. It always starts back up on the first pull.

It happens just enough to piss me off, and make me worry that something isn't right, but not often enough for me to actually do something about it.

If any of this helps you, I don't know. But interested in what you find with your saw.

Nick

 

[KG441c]

Ive got a new 441c that when pinched or binds alil and you pull on handle it wants to accelerate just alil. Anyone experienced this?

 

[zogger]

My 441 rcm was new last may. Has about 9-10 gallons of fuel through it. From day 1 it has had an odd stalling problem. It is not as frequent now as it was when new. Randomly at idle it stalls, sounds just like someone turned it off. Has happened while idling in my hand, but mostly when I set it down and turn my back for a moment or 2. It always starts back up on the first pull.

It happens just enough to piss me off, and make me worry that something isn't right, but not often enough for me to actually do something about it.

If any of this helps you, I don't know. But interested in what you find with your saw.

Nick

You are still under warranty? Wouldn't hurt to tote it to the dealer. That's the second advantage with buying new gear, first is..its new, second is, free warranty work. You paid for that.

 

[blsnelling]

It can be a combination of the metering lever height and the little adjustable set screw that changes when the fresh air butterfly opens in respect to the other butterfly. If not set right, it will affect idle. I've had this problem with numerous 441CMs.

 

[MtnMike]

Hey guys,

Thanks for the information! Some pretty good stuff to think about...

Yes i did have to same problem with one of mine,i sent it back to Brad Snelling and he fixed it,contact him.

Stihlman441: You have a lot of M-Tronic in your shed. Was it just the one saw that exhibited a similar behavior to mine? Andre thinks Brad lowered the carb metering lever (see quote below)--is that what he did? (I'll see if he weighs in on this thread, otherwise I'll PM him...)

I believe Brad lowered the carb metering lever, seemed to work fine after that. Does the saw hesitate when it idles for 10 seconds or so?

Andre: I'll add this to my list of things to mention to the distro when I send my saw to him. This sounds like a pretty good lead, based on what I've learned in the last couple of hours since hearing the term "carb metering lever." In terms of how long the saw needs to idle before it hesitates/dies on retrieval, the shorter the idle interval, the less likely it is to die when I pick it up. I'll have to do a bit more testing, but I think ten seconds would probably cause the same behavior, probably, 60% of the time. If it idles for just a short period--such as the amount of time it takes to re-position yourself for a felling cut or the back cut--it'll keep running. Good question. I think the hesitation and dying is related to the length of the idle period.

One of mine does the same, the other two are fine. There's a technique for dealing with it, but it's kinda tricky. First, walk towards the saw, but then, make out like you just noticed your shoe lace is undone. Be sure and do this within arms reach of the saw or you're wasting your time. Bend over and start fussing with your laces, then make a quick lunge for the saw and get on the throttle real fast before picking the saw up. You've got to be quick with it or the saw works out what's going on.

Shaun: Haha! Try to fake out the saw...funny. I'll try that on my wife's cat sometime...not sure it'll work on my saw. You did mention something that caught my attention: One of your saws does this. What variety of saw do you have? Is it an M-Tronic?

I have the 441RCM version...Even when carrying the saw while it is idling, when I bring it back up, there is a change. Now that you bring this issue up with yours, I will look into it more closely. I never really gave it much thought.

Memory: We have the same saw, the R version. I'll be interested to hear your experience after you "look into it more closely." I'm curious if you find a consistent dying problem with your saw. Get the saw good and warm, then give it a 20-second idle. This will be another good data point along with Stihlman's, Shaun's and FLRA_Dave's saws. Thanks!

...at idle my saw does not sound at all like yours. Mine has a much smoother idle almost no change in pitch or speed, whether being held, sitting on the ground, or even laying on its side there is no difference. Yours seems to be adjusting frequently, or at least sounds that way to me. Completely different from mine. Some info that may help the saw gurus diagnose the problem. How long ago did you buy the saw? Any idea how many hours are on it? Was this a problem from day one, or a more recent development?

Swamp Yankee: Now that is interesting. I thought my saw idled kind of randomly too, but wasn't sure as this is my first M-Tronic saw. Thanks for that insight! As for your other questions: Saw is almost exactly six months old, it has about 16 hours on it, and it has done this since the day it was born. I thought this problem would go away after several hours and tank fillings, and maybe I'm just not there yet, but it hasn't and it's bugging me.

I got my MS441R C-M in October. It had died on me once while I was picking it up off the ground. I can usually count on it sounding like it wants to die when I pick out up off the ground when It is idling for more than a few seconds. Glad to hear that I wasn't the only one this happens to.

FLRA_Dave: Thanks for the feedback. While this may not be a universal defect, it sounds like it's not entirely uncommon behavior. I'll certainly post back here with the results of my quest to fix this in case your saw degenerates to the point of dying like mine.

Mine never gets set down to idle that long. I'll have to play with it tomorrow.

AKDoug: If you're out cutting anyway, I would be interested to hear what you find. See my response to Memory above..get yer saw warmed up, give it a solid 20s idle on the ground, then pick it up with a sturdy grip. Thanks!

have any of you guys changed your mix in gas? say u run 50-1 try mixing a tank at 40-1 or 32-1 and see if that runs any better or if u are running at say 32-1 try running 40-1 or 50-1.

Since having caught up with a lot of the discussion here on ArboristSite, I have decided to run 40:1 using Bel-Ray in my saw...and I can get 91-octane E0 fuel in town. So I'll mix up some of that and see what happens. I don't *think* it'll make a difference, but it's worth trying. Fuel can's getting low anyway...

So, long post. But some great discussion. Thanks guys! Keep it coming. I'll be sure to post back as I continue to work through this and when I find an ultimate resolution.

 

[MtnMike]

It can be a combination of the metering lever height and the little adjustable set screw that changes when the fresh air butterfly opens in respect to the other butterfly. If not set right, it will affect idle. I've had this problem with numerous 441CMs.

Great info--thanks Brad! This is just what I was hoping to hear, that someone knew of something substantive that might be improperly adjusted.

When you say these two items can affect the idle, what aspect of idling do you mean? Does it cause a low idle, a high idle, a "delicate" idle, an erratic idle ('cuz I have that too!)...or any/all of the above?

I'll give the warranty process a chance to work, but this saw's next stop might be your shop.

Thanks again!