Took the head off yesterday to have a Nose about.4 valves on the exhaust side have burnt and cracked, some of the valve guides have broken apart aswell! Anyone have any suggestions as to what might have caused this? Engine Has done 140,000 miles :/ what's the best option in the way of replacement valves??

 

Before having issues with combustion, did you have issues with overheating?

As for that kind of damage, I would invest in a new head. They don't really cost that much, since the engine (in itself) isn't really worth much.