This is an interesting question. I gotta believe that you will find many different temperatures at various places on the block and head depending on where (how far away) the water jacket is behind the surface you are checking. My first try would be to carefully remove the radiator cap and directly measure the water / antifreeze temperature. It should really be your thermostat that sets the temperature and it is the water temperature that the gauge is measuring.


1941 Chevy Master 3/4-Ton
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