Well, I wanted to complete this thread for closure. This has been a very long and very, very expensive journey. I have explained the overheating issue and all that has been done to multiple mechanics and to everyone who would listen. I have replaced, repaired and cleaned, virtually everything in the cooling system... except the temperature sending unit (which was brand new from the beginning).
To make a long story short, I stuck the unit into a pot of water and brought the pot to boiling. I used a candy and meat thermometer as controls. The sending unit was accurate up to 150 degrees, but at 160 it started to rise exponentially. At a water temperature of 180 degrees the gauge showed 215. At 190 degrees it was beyond 220.
Well, the moral of the story is to
always test aftermarket parts.
Dale
