Talk to Stihl yet?
Stihl MS 291 burnt out after 1 hr
- Thread starter west041
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received this reply:
"Dealer sent me picture of your MS291. The bluing on the clutch, break band mark on the clutch drum. And melting of the housing around the clutch drum prove the saw was run with the chain break engaged. This will not be covered under warranty since it is not a manufacture defect. "
So according to Stihl, the only way to melt plastic is to run it with the chain brake on.
Maybe it was on and you did not know until it cooked?
old-cat
Fir Man
Some people just have NO sense of humor! My neighbor bought a brand new MS250 then put straight gas in it and the dealer only charged him for one hour labor. TOTAL!
Rockjock
Addicted to ArboristSite
My suggestion is make a list of what is needed to get the saw back up and running and post it. I have no doubt many here would be more than glad to contribute to your saw repair. Think of it as a peace offering from us to you!
No doubt he will get some used parts.
Chris-PA
Where the Wild Things Are
Certainly a good illustration of why a clutch should not be located in proximity to a material that can melt - or at least if it is it should be one that is not difficult or expensive to replace (like a clutch cover).
If a clutch is slipping over a period of time, for whatever reason, then some percentage of the mechanical energy of the engine is going into the clutch. Since that is a lot of energy and the clutch cannot dissipate it well, it gets damn hot fast.
If a clutch is slipping over a period of time, for whatever reason, then some percentage of the mechanical energy of the engine is going into the clutch. Since that is a lot of energy and the clutch cannot dissipate it well, it gets damn hot fast.
Rockjock
Addicted to ArboristSite
Agreed but who would think a brand new saw would have clutch slippage? I wonder if say at the dealers they took the saw, brand new in a box and fuelled it up and fired it up for a bit and it started to smoke just like the OP's did how would they explain it to stihl? I dunno and we prolly will never know what caused it.
Chris-PA
Where the Wild Things Are
Yeah, but it's a clutch on the output of an engine, and with a brake band on it too - it is impossible that the designers didn't understand the high likelihood of it getting very hot. No conscientious engineer should have signed off on that.
I have only had one saw in 40 years of treework do that, it was an 036 quick stop.
What I think... Just my opinion.
Clutch slipped for whatever reason, lead to heat which destroyed the clutch drum bearing. The clutch from wobbled which lead to poor contact between the clutch pads and the drum, which lead to more slippage and heat, drum wobbled enough to contact the brake band, generating more heat.
Clutch slipped for whatever reason, lead to heat which destroyed the clutch drum bearing. The clutch from wobbled which lead to poor contact between the clutch pads and the drum, which lead to more slippage and heat, drum wobbled enough to contact the brake band, generating more heat.
That would have to be tested.
I agree.
sunfish
Fish Head
Now that is some of the best advice written here!
Just got off the phone, Stihl says no go. He said that the grooving around the clutch drum was too obvious to be anything else. He said if there was clutch slippage then the bearing would have fallen apart and you would have seen a lot more damage before the plastic melted. I have to take him at his word there because he has seen far more of these situations than I have. As for how many burned out 291s he's seen, I didn't ask, but you have to start to wonder, as others have, about the engineering choice of putting plastic in such high heat areas. I guess people really like a lighter saw.
Anyway, worth a try, the suspense is over. Final diagnosis from Stihl - chain brake left on. Lesson learned, even if I don't see it that way. You really have to baby these plastic homeowner saws.
Anyway, worth a try, the suspense is over. Final diagnosis from Stihl - chain brake left on. Lesson learned, even if I don't see it that way. You really have to baby these plastic homeowner saws.
Rockjock
Addicted to ArboristSite
I own or have owned quite a few of these plastic saws, 017, 021,023,024,025 MS 250 even a MS 290 all have not been babied and all owe me nothing because of the work I have gotten out of them. To me this is a case of a bad one getting out. make a list of what you need to make it right and we can go from there.
jughead500
Sasquatch
If you don't get it fixed look into parting it out.may be a loss but im sure youll make enough to buy a good used saw.
sunfish
Fish Head
This type of construction actually makes a heavier & bulkier saw.
The blue clutch said it all, in your very first post. I also told you what was up in my very first post.
There is nothing wrong with this series of saws! They are in fact very durable, well made saws for what they are, and we don't need a thousand posts to discuss this fact.
Nevertheless it's been fun gentleman.
Nothing like someone just itching to say "i told you so". I'm glad everyone had fun. I'll draw my own conclusions about the saw, thank you.
