I have a Stihl 028 with an allegedly busted oil pump - for chain oil. I took it to an authorized dealer and they said it would be $150 or $200 to repair. Its not even worth $100, so I am inclined to either toss it, or repair it myself. I have never worked on a chainsaw before, but I am pretty mechanically inclined. Anyone have experience changing a pump? (I will of course check for clogs, etc, before I actually change the pump, but since an auth dealer at a reputable repair shop said its busted, I figure its likely). Also, any idea where I can get a replacement pump?