My dad gave me his barely used 009...fired up immediately after sitting at least 20 years. BUT the oiler is not working. It is the type that works off of pressure--not gear driven. I removed it, every hole is clear, ran vacuum through it and the plunger is moving freely.... can't figure out why it is not working. the local stihl mechanic was no help. Does anyone have any tips? One site someone mentioned something about the muffler as this "pump" just uses crankcase pressure to push oil. Any help would be appreciated!