Temperature gauge is high

[hemicharger69]

1963 Ford Thunderbird 132,000mi factory orig 390ci auto hardtop. No aftermarket mods.

Recently replaced steering pressure hoses (1) pump to steering box (2) steering box to wiper motor. No leaks.

While I was at it, I replaced the water pump. Replaced bottom radiator hose. No leaks.

Now the temperature gauge reads hot. Almost to the far right just below the end 1/8". It always read above center since I bought it last summer. Temp gauge stays hot even after engine is off for some time. When engine is stone cold, the temp gauge is far left. As engine warms up, the temp gauge goes to far right just shy 1/8" from maximum right.

I have bled the cooling system by running engine on parked uphill with heater/defrost on, overflow cap off. Adding coolant after stone cold and repeated process couple times.

New temp sensor replaced last summer. Checked tension of belts. Not too tight or loose. Alternator is new. Water pump is new. Steering pump spun freely when I replaced hoses. Could it be the thermostat? Why would it stop working after I replaced the water pump? It was fine before water pump replacement.

Is this electrical false reading. I'm afraid of frying the head gaskets. I will get an infrared temp measurement tool. Where do I take the temp reading?

 

[captrick]

Hi Hemicharger, it sounds very much like the thermostat, take it out and see if the temperature still goes to hot. You can take the thermostat out and put it a pot of water and put on a stove with a meat thermometer in it and see if it opens and at what temperature. If you still have a problem take the lead off of the sending unit and replace with a temporary jump to the plug on the firewall. The temp gauge measures the resistance in the sending unit and that tells you if it is running hot or cold. If the resistance in the wire is high it will give you a false reading also. Good Luck Rick

 

[captrick]

Hi Hemicharger, it sounds very much like the thermostat, take it out and see if the temperature still goes to hot. You can take the thermostat out and put it a pot of water and put on a stove with a meat thermometer in it and see if it opens and at what temperature. If you still have a problem take the lead off of the sending unit and replace with a temporary jump to the plug on the firewall. The temp gauge measures the resistance in the sending unit and that tells you if it is running hot or cold. If the resistance in the wire is high it will give you a false reading also. Good Luck Rick