Looks like I won't make it to TBO. I fly behind a 2000 O-540 B4B5. 970 TTSN The oil analysis said elevated levels metal. Just in the caution zone. If I change it at 25 hr. it is normal but has higher levels of metal than it had 200 hours ago.
I run Exxon Elite 20-50. Champion filter. Normal change both 25-35 hr. Once in awhile will go to 40-50hr. I fly most weeks. Once or twice a year it will sit 2-3 weeks.
I think the problem came from 2001 prop strike. Lycoming rebuilt. Sat till 2006 with 30 minutes on the engine.
Last change was 35 hours. I cut the filter and washed it out in solvent. I ran a magnet through the solvent and got a very small amount. Very fine like flower. Think of a pencil eraser cut into 6 pieces. The amount was equal to 1/6 maybe 1/4, not much.
Took the magnet to the local engine shop, a well respected business, never heard a bad word about them. The owner said the only metal that looks like my sample is cam VS lifter.
I am looking for your knowledge related to this issue.
How long before it really starts to get bad and I got to tear into it?
What should I do now?
Is it OK to keep running it and monitor it every 25 hr?
How much should a tear down inspect, replace cam and lifters for sure, cost?
Does the engine have to come out to do the cam?
While they are in there I was thinking rings, bearings and freshen up the heads?
Anything you want to add I will appreciate.