Diablo - been there, done that. That's what I initially thought. The screen is clean every time I check it. I switched tanks, all lines, etc., same problem. Filtered clunk. Has me and others puzzled, but going back to Valvoline fixed it. Why, I don't know.

3-Point - Yeah, I should have talked to them long ago, but was a crummy flying day today and was sitting here thinking about it and decided to ask the RCUniverse to see if anybody else had run into this. It is no longer a problem as I won't use the oil again.

Thanks for the replies.

Hall