Brand new MS391 meltdown

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The arrows are where the brake band connect . They are 💯 fine. The oil line coming from the oil tank is good as well . Looks worse than it is. The tention on the band keeps it right against the clutch drum . I can’t see how it could move much.
 
Looks quite good, the oil pickup/black rubber hose at bottom right in thee top pic looks like it has been heat damaged, should be replaced. The vert top brake band holding lug looks to be either missing or still under some of the melted plastic, only tell for certain when the brake band is installed and all linkage connected to the brake handle.
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It’s held in place with a screw at one end and attached to the brake mechanism at the other and neither of those areas was effected by by the melted plastic. The areas that the band might ride against are still there.

I bet it will be fine. What you can do to your own saw and what a dealer can do and stand behind with his reputation are different.
If I was the dealer I would have replaced the crankcase, if it was mine I would tried to do as good a job as you did.
 
I bet it will be fine. What you can do to your own saw and what a dealer can do and stand behind with his reputation are different.
If I was the dealer I would have replaced the crankcase, if it was mine I would tried to do as good a job as you did.
 
I have the new parts on order . I did not get the case at this time . The chain break strap fits in place very nice and firm after the case clean up with a drimel tool. Before and after cleaning the case. View attachment 1242343View attachment 1242344
You did a good job on cleaning it up but I’d suggest re-considering a new case. Note what Jerry said about hoses and brake band. Not to mention new seals. It’s a very simple process to rebuild one. Enjoy the process, you already have a good working one now and winter is a great time to tackle it.
 
Experience says you will most likely be fine. See a lot of these over the years. If you want perfect, get a case. If you want a saw that does what it needs to, you will be good.
All that said, be weary of erratic running after. It can be a bit rough on the seal and crank bearing on that side.
 
There are times when it is best NOT to do a job like this at a dealer. Once you work on it, you own it. Age and condition of saw are the main factors. And lately- sentimental value. (It has been in the family for years). You must tread very carefully in those situations.

As far as you fixing yourself, go for it. Yes much less cost without labor. As long as you are able.
 
There are times when it is best NOT to do a job like this at a dealer. Once you work on it, you own it. Age and condition of saw are the main factors. And lately- sentimental value. (It has been in the family for years). You must tread very carefully in those situations.

As far as you fixing yourself, go for it. Yes much less cost without labor. As long as you are able.
This was my very first chain saw and had 1 hour of run time on it. I’ve never worked on a chain saw before but worked on many different types of small and big engines in my life. My goal is to have a very good back up chainsaw
 
All put back together, oil pump adjusted. Zero binding on the Chain brake. Zero binding on the chain sprocket/clutch drum. Chain brake works perfect. Chain Oiler working great. Saw seems to be 💯 ready to go. 🙏🏻 I even sharpened my first chain and put it on this saw. Nice to have a back up/ Second saw on my trailer. The low Idle seems to be very high still. High Idle seems to be very high as well. I’m going to take it by the dealer to see what they think🤔 As this is my first chain saw not sure on what the idle should be like but comparing it to the second saw I purchased (same exact model) it idles much much faster.

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All put back
 
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