Well it finally happened...... After 1600 trouble-free hours with my O-320, a little rain has fallen. Made two great trips to Iowa last weekend and got home on Sunday and dropped the oil for the change. I made the mistake thinking on the way home how great she was running.......
I did my usual compression check and saw 77/80 on 2-3-4, but #1 was 60/80. Leak out the exhaust - grrrr (all 77/80 50 hrs ago). Talked to those more smarter than I (Professors Horton, Lane, Peterson, et al) and consensus was fly it a bit, test it again - that did not help - no joy. Exhaust leaks don't heal and need to be dealt with.
Made a "Mike Bullock Wonderbar Special" (TM) valve compressor(seriously, was that a great writeup he did or what!)
Then pulled the springs and keepers. Valve was silky smooth in the guide and seated well when pulled back, so that was good. Dan suggested spinning and banging the valve on the seat just in case there was a piece of junk on there, so we tried that and shot this video thru the top plug hole with my celly.
I think you can see the problem area if you look closely, but do offer up any observations of the valve sealing surface.
We did try a compression check after doing the "Spin and Bang" - same story 60/80 and exhaust hiss. Took me less than 30 min to get the baffling and other stuff out of the way to free up #1 Jug (it looks like the easiest of all to get free), then I had to go out of town for the weekend. Jug will come off tonight with the help of Alex P.
New jug looks to be $1000 or so. So New Cylinder, rebuilt cylinder, or fix the valve and seat........that is the question....please offer opinions, rationale and cost estimates.........
To answer the questions you are all dying to know....
- These are ECI Group B Cyls from 2005
- LOP other than takeoff, CHTS balanced and in the 325degF range
- 50+% Mogas, 92 no EtOH
- Rattle can Primer
- Dog hair in the cockpit
Thanks for commiserating................ Ha!