260Driver wrote:Arrrgghhh! Just out of annual, compressions on my IO-540 = 79, 76, 79, 77, 78, 78...not too shabby, right?

then I got the oil analysis back...showing a little more metal than the previous two (nothing showing in the filter, yet).

I'm thinking a borescope is in order...

Nothing in the filter is great. Change the oil and filter at 25 hours and see if that fixes it. If it keeps making metal at 25 hour change keep a close eye on the filter. Use a magnet to look for iron. A few flecks here and there are ok. If the magnet is covered with fuzz or small pieces it is coming from somewhere and you will need to pull 3 jugs off one side to get a good look inside. Next oil change pull the large screen from the oil pan and look for chunks, they never get to the filter.

Happy metal hunting

Clean bill of health following the borescope not a spot of rust and could even still see cross-hatching