It looks to me like the engine was getting some metal debris but the bearings were trying to do their job and were able to eat most of it.
I would use the pressure washer to blast away the initial grit in the engine with all of the oil plugs removed. I would then mount it on an engine
stand and use gun brushes to clean each oil passage and a stiff car wash bristle brush (not
metal) to clean the whole block and bores again.
I would then inspect the block for any wear at the tops of the bores, look for cracks everywhere
on the block, and blow dry and oil the metal surfaces. The bores may require a hone job. If
so you will have to clean the block again after the work.
Stay in touch on your work on the block with the
people on the board and we can walk you through the whole process. Tom V.
