[jsgold]

I would ask is the car loosing coolant? What happens to the hoses when the car heats up? Do they swell badly? A plugged converter can cause overheating, yes. A blown head gasket can do some bad things as well. My dad's old 89 Olds had a cracked head and blown gasket, and it leaked coolant into oil (check for this too...) and built up terrible pressure in coolant system, as the leak blew pressure right into water jacket. I would suppose either of you could be right, but check for - oil in coolant, see if leaking coolant, any oil in coolant, swelled hoses, and, if possible maybe the best test would be to check compression in each cylinder, to see if a cylinder has very low pressure. Your guy might be right, but you never know. Normally there is some kind if leakage as far as fluids are concerned. But let's see what others think here as well.