Well, if it cools when revved at idle, it could indicate a waterpump problem as it needs the speed to circulate. But if it cools only when driving I'd guess the radiator itself. Dumb question: are you sure the hoses aren't connected backwards? It happens! Ken
Hoses are a-ok. Can ran fine for the 1st 800 miles after the rebuild. Mechanic suspects that crap worked up to radiator from around the cooling system, and that may be the problem. Gonna tear out the radiator, get it fixed, and see what is what.
One other thought...head gasket. I'll bet 10-1 it's the radiator itself but I do seem to remember someone once saying a blown head gasket can cause heat spikes. I bet you already know it's not because you've seen the coolant and there's no oil in it, but check if you haven't already. Ken
No oil in the coolant. So, head gasket is ok, too. Gonna yank out the radiator, get it cleaned, then see what happens. Can buy a better than original Ron Davis for about $900, or go original for about $1500. hmmm.......... looks like Ron Davis if I have to go that way.
Slow leak at the water pump, caused a bubble of massive proportion. When I bled the cooling system, I didn't have enough persistance. If I had bled it for 15 minutes, I might have started to see the problem. Mechanic is fixing the water pump now, car will be road worthy tomorrow!!! So, all's well that ends well.
