Last week I bought an ancient Stihl FS36 whipper-snipper to replace the bloody dead one. Four weeks after the cut my finger joint still hurts and won't straighten fully. The Stihl was in so-so shape, wouldn't start easily, but at $56...
So, me being me, the first thing (literally) that I did was take it apart. Completely, down to removing the piston ring from the piston.
What for? firstly cleaning, secondly figuring out whether and what parts might need replacing. The pics don't actually show the Grand Puzzle View (all the parts in one pile), because it took me so long to get the front cover off, which is required prior to disassembling the cylinder head further.
First you need to remove the clutch bell (one super-slim Torx driver which I don't have), and then the clutch needs to be screwed off the shaft. I chipped two of the cooling fins on the flywheel before learning the right way to block that shaft: stuff a rope into the cylinder until the piston safely rests against the rope. Even after that I had to fabricate me a Special Tool to apply the large amount of torque where it would do good.
The plastic parts and the (coked-up) exhaust I brushed heavily and soaked overnight, the other stuff swallowed loads of carby cleaner but in the end everything looked fairly clean and good for its age (which is 10+ years).
Of course, the million-dollar question remained: would it ever start again?
Actually, it did. Not on the first pull, hell no, but it works reasonably well
now, and allowed me to cut the cobbler's pegs and all the other weedy stuff
behind the house back down to reasonable amounts.