I own a Stihl MS 280 with very low hours. Was bought new. Still has original chain. While sawing some locust firewood the chain appeared dull. Found oiler not working. When I went to check the oiler I found a bolt had come loose somewhere in the case and had bounced around inside until it had destroyed the oiler assembly and had broken off several pieces of the case. Even with new oiler parts there is so much damage that it can't be repaired without modifying or replacing the case.