Quote:



I realize the head has been warped, or head gasket blown, somehow, as there appears to be water in the oil.




If the head gasket is blown or the head is warped, that would explain both the overheating & the cooling system becoming pressurized beyond it's abilities to contain pressure.

I can't tell you if the 2,500 PSI water stream used to flush the engine tore through the head gasket, but I sure wouldn't rule that possibility out.