DAR
Thank you for the reply, this latest batch of failures is usualy found when you cut open the filter and find small slices of the piston pin plug in the oil filter.
If you are smart you pull the cylinders off and find the plug that has the problem, it is the ridge that forms at the BDC point of the oil control ring that is the root cause of the problem.
I have now had this happen to three engines that have been under my maintenance control since overhaul, these engines have cylinders from three different manufacturers............. I am trying to find a common thread to the problems.