I got the new water pump installed. Drove to work and back with no evident leaks. I also replaced radiator and hoses. Original radiator will be overhauled and kept as a spare. The car had been down for a couple weeks and it was good to be back on the road.

The start-up procedure involved new coolant circulating and evacuating the usual air bubbles. For 20-25 seconds the temp gauge was in the hot zone as the thermostat was heating up and then opened. The engine was just idling with no load.

This got me to thinking: Could a head gasket or cylinder head be damaged by this momentary overheating? The gauge always spikes up after shut-down as the coolamt stops circulating. Would it take prolonged running under load to damage something?
I know that cracking, warpage, and gasket problems can occur with overheating, but has anyone ever overheated a B18/20 to the point of hurting something?

I know that cast iron heads are a lot tougher than aluminum. In the `60s we towed a travel trailer with a Chevy 283 CID. Many a time the "hot light" would come on going up a grade. Open up the heater {even in summer), make the grade and coasting down the other side the light would wink off. No gauge! Never discerned any damage. Is ignorance bliss? How tough are our beloved "bricks"?