Originally Posted by Thriftmaster_Phi
Any reason such a crack could not be Brazed?

Brass will not stand combustion chamber temperature. The crack is between the valve seats. It might be repairable by pinning or arc welding the crack with nickel welding rod but then both valve seats would have to be replaced. That's about a $200.00 fix or more, plus all the other machine work involved in rebuilding the head.
Jerry

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