It was fun, good luck

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Rod bearings should be checked.


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I'd say you have a case of which came first, the chicken or the egg!!!
Your exhaust valves and respective seats were going bad first ...super heating the head, valves, valve seats, guides and or seals. Burning them up with +1500 degree exhaust gases.
Probably all of the above were damaged
Normally this is caused by normal wear and tear ...with very little maintenance in regards to checking and setting proper cam lobe clearances!
So my gut is telling me you shot yourself in the pocket book.

Well put.
Steve

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