Sold Sthil saw unknown model

[BeerRanger]

Hi guys, I just found this page while searching for details on the saws I'm tasked with maintaining at work. Right now I'm trying to match up our 7 Stihl chainsaws with the 6 owner's manuals I've found in the file cabinet.

Right now I'm trying to figure out the model number on one which is missing the model badge on the side. The parts code starts with 1140. The serial number is 289605691.

From what I've searched so far it seems to be a MS311 or MS391, however I only have manuals for the MS 290/ 310/ 390. We have 3 of those manuals for some reason, with 290 circled on 2 of them and 390 circled on the other one.

Thanks in advance for any help.

 

[cookies]

measure the cylinder bore width or try using the cast part number on the cylinder to reverse look up what it is used on