On Cylinders 1 and 2, the top 2 piston compression rings were extremely brittle, and cracked into pieces with light pressure. The smallest pieces of the rings were difficult to remove from the ring "trough" in the piston, but eventually they came out. they were stuck in the groove, had to be persuaded/picked out. there was no apparent damage to the piston, although they haven't been thoroughly cleaned and inspected. the oil rings were in relatively fine condition. The compression ring pieces had a cross section that looked more like a "T" than a rectangle. See the pic of the pieces on the magnet for detail.
IMG-8832.jpg
https://i.ibb.co/5RrWZZb/IMG-8833.jpg (piston ring pieces)
https://ibb.co/pJmRrWt (magnet pieces)
https://ibb.co/Dttfpvy (pistons 2 and 3 comparison)
comparison of the 2 and 3 pistons shows that combustion carbon had found it's way past both compression rings on piston 2, which likely confirms the suspicion that blow-by was responsible for the initial complaint of oil exiting through the breather.
head and cylinder are at the machine shop now, new springs and seals for the valves, and a hone for the cylinders.
re-assembly in a week or two.
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