Engine change problem. Water pump impeller chewed up....Where's the pieces?

[JFP in PA]

Actually, I'd go the other way around; your water pump may have came apart (on the track, if memory serves), and the bits blocked some of the water passages to your head and more importantly, the oil cooler area, and that is probably what started the fatal chain of events leading to your rod failure. Not that uncommon, this is why Jake is suggesting changing out the water pump every three years, even if it is working fine...........

Getting all the bits out is a major pain, probably will require total disassembly unless you are very lucky.

[Jake Raby]

If one of those pieces, as small as a pencil eraser gets in the right cylinder head capillary, you'll have a cracked head.

You must disassemble the entire cooling system and clean every part.. A flush won't cut it.

If it were mine I'd change the radiators and throw the old ones away.. Gotta take this seriously, if not you'll pay the price the hard way..