Thought I'd post here since you guys know a thing or two about tuning engines.
Engine is a basic OS 40 FP running 10 x 6 prop. Today I literally couldn't get it to lean out and scream, it stayed slightly rich no matter what. I turned the needle valve in about a half turn more then it started to die which is when I knew I had gone too far. It simply never would develop that high end scream like it should. It blew a little smoke indicating a slightly rich mixture as well.
I will say I noticed a few air bubbles in the fuel line, maybe an air leak somewhere? I also am running some old gas, would that make it less likely to lean out?
Thank you!