My engine had a rod bearing failure due to a crank oil passage plug falling out, not a catastrophic failure unless you consider my wallet. Very little material was found anywhere the bearing just beat around a bit. There were some bits of copper in the case when disassembled.
I am having the engine mounted and the fender mounted coolers cleaned but was wondering how I would flush the lines forward to the cooler in the fender. The PO installed these through the rockers and I did not want to pull the lines out. I used to do a lot of work with hydraulics and remembered that we used to blow foam plugs through lines prior to commissioning systems to clean out any asteroids that were left over from the construction. I went to a hydraulic shop and sure enough they had them in several sizes and gave me some. I used about 20 psi of air to blow them through several times and it worked very well. The oil that was collected from the end of the hose I am happy to say had no bits or pieces in it, I feel that I have addressed all the places that debris can be laying now.
W