Stihl Ms 391

[Davidkaram]

Sounds like something is jamming in the squish band.

Use a screwdriver to pry out the plugs on the front of the muffler. Then unscrew the muffler with a T27 torx driver.

thank u I just did it and took it away and I was able to get a piece of metal from the cylinder, now i have to figure out how to take apart the cylinder and the carb from the rest of the saw,

 

[Davidkaram]

Any story of what was going on before this happened? Were you running it or is this something you acquired?
I would pull the clutch drum and clutch off of the other side to make sure nothing is jammed in the clutch/case.

thanks for ur reply actually i bought it, not working, not sure what happened to it, I removed the muffler and took a small piece of metal from it though its still stuck doesn't move much

 

[Davidkaram]

Well thank you all for help, I removed the cylinder apart and i was able to see that the piston had some parts shredded from it on the down side i will soon replace it and put it together just a quick question, I didn't see any base gasket for this MS 391 do u know if it needs one? and what good affordable type of gasket sealant you recommend using? any suggestions on where to buy good after market parts for it? thank you.

 

[Cope1024]

Go to the beg for manuals section and ask for the IPL and service manual for your saw.

 

[a. palmer jr.]

If it's anything like the 390 you will need some sealer for the engine, no gasket. I use Motoseal which can be bought at NAPA or O'Reillys.

 

[JonCraig]

Can you post pictures of the piston and cylinder?