Brand new MS391 meltdown

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Still need to know what plastic melted around the clutch drum has to so with the saw starting.
Nothing to do with starting. Depending on how hot the clutch got, the clutch could be defective due to weak springs, the brake could be permanently fused in the on position, oiler might not work and crank seal might be shot but it will probably start unless the seal is really bad.
 
We sold $164,000 of Stihl in October. Any instructions we give are read the manual.
Running anything above low idle for two minutes with the brake on makes no sense under any circumstance.
The dealer making any carb adjustment on a new saw is non existent other than maybe idle mix. Will have nothing to do with high idle. The high speed adjustment even if there is one is maxed out.

Story is off.
 
Would using 40:1 canned gas cause a leaner low idle if the saw were factory tuned for 50:1? Causing clutch to to engage at low idle with brake engaged?

I have no experience using the wrong fuel mix for the carb tune (yet). My understanding is changing from 50:1 tune to 40:1 requires a richer mixture.
 
The saw is in the dealer’s hands so I can’t take pictures.
One time we needed air tools on a dock job with no electric power available. I went to Sears and bought the biggest gas engined compress they had. Brought it to the job site, pretty proud of myself, and started it up. I seemed to be rapping a bit. I shut it down and one of my employees asked if I had added oil. "Oil? Its brand new why should it be low on oil" We put in a quart and a half of oil and and it did start up and keep running, more quietly. Guess the little bit of oil from the factory saved it. Not all of us were born knowing how to do everything. Good luck on the Clutch repair.
 
Not all of us were born knowing how to do everything. Good luck on the Clutch repair.
Very good point.
My dad was 21 year military and never home.
He came home one day, told me to check oil in the 71 bronco " I was 13 " the oil looked low so added a quart.......to the transmission fluid 😳.
Mom drove us to school next day and lost transmission and dad called me a ******* when he found out where I added oil.
Life lessons.
 
I don't believe I'd ever post pictures of any self inflicted damage when that damage was caused by rank ignorance. In fact I would have never posted the comment in the first place. No Stihl dealer or any other dealer of any other brand, Husky, Echo or whatever would warrant self inflicted abuse that I know of but I'm sure all of them would be more than willing to sell the owner replacement parts and / or charge them the labor to repair it.

Common sense should tell any owner that if the saw is idling so high that the clutch is attempting to engage when at base idle that the base idle is too high and a simple idle screw adjustment is all that is required, but then there are a lot of people today that lack common sense.
Ya, We know you’re perfect.
The op was just looking for advice. This may be his first ever chainsaw.
 
I installed a new Stihl carburetor on my MS250 and it was idling fast enough on low idle for the chain to move pretty fast. If Stihl can sell a new carburetor adjusted fast, I suppose they could sell a new saw idling fast. When I bought a new saw recently, the dealer (Gallant & Son) fueled it and started it to make sure it was running correctly. I don't know if they adjusted the idle, but the chain does not move on low idle. I usually start the saw on the ground with the chain brake not engaged. This requires making sure that the chain is not in contact with anything.
 
I installed a new Stihl carburetor on my MS250 and it was idling fast enough on low idle for the chain to move pretty fast. If Stihl can sell a new carburetor adjusted fast, I suppose they could sell a new saw idling fast. When I bought a new saw recently, the dealer (Gallant & Son) fueled it and started it to make sure it was running correctly. I don't know if they adjusted the idle, but the chain does not move on low idle. I usually start the saw on the ground with the chain brake not engaged. This requires making sure that the chain is not in contact with anything.
Carbs are never sold with intention of them being adjusted just right for your saw, nominal factory setting and just a starting point so you can get the saw running and do a correct tune. On the other hand, I can't imagine a Stihl dealer handing a new saw to a customer without having started it and making sure it was running right.
 
Carbs are never sold with intention of them being adjusted just right for your saw, nominal factory setting and just a starting point so you can get the saw running and do a correct tune. On the other hand, I can't imagine a Stihl dealer handing a new saw to a customer without having started it and making sure it was running right.
Thing is, most new saws have no adjustment. They are adjusted when they come out of the factory at Va Beach or wherever. And, they are against the limiter.
So, I am not saying that a saw set at idle can not set and burn itself up.
But, I don't believe it for a minute.
 
I installed a new Stihl carburetor on my MS250 and it was idling fast enough on low idle for the chain to move pretty fast. If Stihl can sell a new carburetor adjusted fast, I suppose they could sell a new saw idling fast. When I bought a new saw recently, the dealer (Gallant & Son) fueled it and started it to make sure it was running correctly. I don't know if they adjusted the idle, but the chain does not move on low idle. I usually start the saw on the ground with the chain brake not engaged. This requires making sure that the chain is not in contact with anything.

Replacement carbs are not set to anything.
 
Carbs are never sold with intention of them being adjusted just right for your saw, nominal factory setting and just a starting point so you can get the saw running and do a correct tune. On the other hand, I can't imagine a Stihl dealer handing a new saw to a customer without having started it and making sure it was running right.
Not sure what state your in but I've never bought a new saw from a dealer and witnessed them starting any of them.
Reputable dealers of Stihl, Husqvarna and Echo.
Perhaps it's something the consumer needs to request. ?
 
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