Well here goes. I have a 1963 D19 gasser. I have removed the head, ground the valves and replaced the head gasket. I removed the radiator had it flushed and pressure tested. I have removed and inspected the water pump. The impeller spins with the pulley. I reinstalled with no leaks. I have replaced the radiator cap with proper 4psi replacement. I have replaced the thermostat with a 160F. I have replaced the temperature gauge and sender. There are no leaks in the cooling system.
The engine will run for several minutes then start to overheat, peg the temperature gauge to hot, and boil over. So I removed the thermostat and ran it without it. The engine ran fine for 30 mins without overheating but the temperature gauge never moved from the cold side. So I figured I had another bad thermostat and replaced it with a new 160F. Same story as before run for several mins, temp gauge peg to hot, and radiator boil over.
Any ideas on what could be wrong? I am running out of ideas.
The engine will run for several minutes then start to overheat, peg the temperature gauge to hot, and boil over. So I removed the thermostat and ran it without it. The engine ran fine for 30 mins without overheating but the temperature gauge never moved from the cold side. So I figured I had another bad thermostat and replaced it with a new 160F. Same story as before run for several mins, temp gauge peg to hot, and radiator boil over.
Any ideas on what could be wrong? I am running out of ideas.