Stihl MS 291 burnt out after 1 hr

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What's the black stuff between the outer casing and the brake band? It doesn't look like the entire brake band is all shined up like it would be if it was engaged. Maybe the black stuff built up and was pushing the band into the clutch. Explains the shiny spot on the clutch but not the band
 
Cool. All I'm saying is, I can put up with people telling me I bogged the saw in deep wood, or some other theory. But telling me I left the chain brake on is kind of ridiculous, or saying that it doesn't matter because the end result is the same, as Andyshine did. The reason does matter to me, because a chain brake mistake like that is unforgiveable IMO. did you watch Doug's video in the other thread? You'd have to be a complete moron to run a saw that hard with the brake on, even with it completely buried in a tree. It just goes against everything I was taught and it insults me for people to suspect that I did it.

Also, Doug just barely started the smoking after 7-10 seconds with the brake on. You'd have to run it for another 7-10 seconds to do what I did to the saw. Revving the engine while having the chain stationary for even 2-3 seconds would be a huge oversight in my book.

Bottom line is that I should have noticed the smoke well before I did. In that moment I erred. But the cause still matters to me.
 
Cool. All I'm saying is, I can put up with people telling me I bogged the saw in deep wood, or some other theory. But telling me I left the chain brake on is kind of ridiculous, or saying that it doesn't matter because the end result is the same, as Andyshine did. The reason does matter to me, because a chain brake mistake like that is unforgiveable IMO. did you watch Doug's video in the other thread? You'd have to be a complete moron to run a saw that hard with the brake on, even with it completely buried in a tree. It just goes against everything I was taught and it insults me for people to suspect that I did it.

Also, Doug just barely started the smoking after 7-10 seconds with the brake on. You'd have to run it for another 7-10 seconds to do what I did to the saw. Revving the engine while having the chain stationary for even 2-3 seconds would be a huge oversight in my book.

Bottom line is that I should have noticed the smoke well before I did. In that moment I erred. But the cause still matters to me.
So make a parts list.
 
Yah.... First in the list
Get an 036 or 360 lol
Much better saws
 
I'm thinking that you may need a lighter spring on the clutch assembly to keep the clutch engage in a lower RPM that would stop the clutch from making to much slip and heating up the clutch drum. My personal opinion I think the composite bodies are a bad design .nothing should be so easily melted next to a clutch assembly.

If the clutch engaged at a lower rpm the chain would be spinning at idle, and turning down the idle too far would stall the engine.

041 take it easy man, I'm not so bad once you get to know me.
 
Yah.... First in the list
Get an 036 or 360 lol
Much better saws
Or an 044 440 441 046 460 461 064 066 660 372xp 385xp 390xp 576.................. they're all better saws. But it doesn't fix his problem. Maybe stihl should just drop every model below a 362 and we'd never have to buy parts again. Smfh
 
True true ... U would have to lower the idle to a sweet spot but like I said why is this happening ? U can't just assume the chain brake is the colprat . I've had guys give me composite saws with there hands on there head telling me It just burned up with out any reason. I've bought housings on feebay to repair them but I was unsure why it happened. It worked great after I was done but would it do it again..... Who knows lolol
 
U know to drop the home owner smaller saw wouldn't be a bad idea
 
Some people don't even know what the chain brake is, or what it does. Every owners manual says set the chain brake when starting the saw, now add in the fact modern saw are set to high idle automatically when you engage the choke. When people start the saw, they have no idea that the high idle is normal or not. Some figure it out before it's too late, some don't.



 
Cool. All I'm saying is, I can put up with people telling me I bogged the saw in deep wood, or some other theory. But telling me I left the chain brake on is kind of ridiculous, or saying that it doesn't matter because the end result is the same, as Andyshine did. The reason does matter to me, because a chain brake mistake like that is unforgiveable IMO. did you watch Doug's video in the other thread? You'd have to be a complete moron to run a saw that hard with the brake on, even with it completely buried in a tree. It just goes against everything I was taught and it insults me for people to suspect that I did it.

Also, Doug just barely started the smoking after 7-10 seconds with the brake on. You'd have to run it for another 7-10 seconds to do what I did to the saw. Revving the engine while having the chain stationary for even 2-3 seconds would be a huge oversight in my book.

Bottom line is that I should have noticed the smoke well before I did. In that moment I erred. But the cause still matters to me.
What you did was press the brake handle a wot while cutting, that's all. Not fully engage the brake by locking it forward but merely apply some pressure on it while cutting and when saws operate at 8-10k rpm it don't take much to generate too much heat. You need to read this so you are contious of this and don't repeat the mistake. l consider myself experience with saws and l have done this while trying too cut stumps low to the ground, however without the results you got. I cannot believe after 19 pages nobody has considers this, its not that hard to work out what happened.
 
What you did was press the brake handle a wot while cutting, that's all. Not fully engage the brake by locking it forward but merely apply some pressure on it while cutting and when saws operate at 8-10k rpm it don't take much to generate too much heat. You need to read this so you are contious of this and don't repeat the mistake. l consider myself experience with saws and l have done this while trying too cut stumps low to the ground, however without the results you got. I cannot believe after 19 pages nobody has considers this, its not that hard to work out what happened.

Interesting idea but not viable. Go to your saw without running it and move the chain by hand and then apply some pressure to the chain brake. No resistance at all. It is like a mouse trap trigger. it is off or it is on. There is no in-between.
 
Interesting idea but not viable. Go to your saw without running it and move the chain by hand and then apply some pressure to the chain brake. No resistance at all. It is like a mouse trap trigger. it is off or it is on. There is no in-between.

Agreed. I thought this was possible until I did the same test today with a 271. It's definitely an on/off situation.
 
Both of my saws will make it obvious when I forget to turn off the chain brake...by not moving the chain. I even accidentally bumped the chain brake on when I was bucking and I knew immediately when the brake engaged.

Just sayin'.....

Yep, my sentiments exactly. Too bad Stihl didn't agree with me.
 
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