I have a '92 f 150 that is driving me insane! Started out with a squaling water pump. and a cracked radiator..... No cooling trouble..... Renewed water pump, radiator, cap and thermostat. (Temp. sensor about 6 months old worked fine). After changes water gauge going higher than it ever did before. even got over to the "H" (red). blew bottom rad. hose. (renewed). Changed thermo. no help. removed thermo. engine stayed cool for about 3 weeks. This morning engine temp started getting much to high while driving to work. Top and bottom rad. hose tight and hot. Rad and cap cool to touch. What's going on. Please help.

 

Do you have anti-freeze in the over flow? If you remove the cap is your radiator still full? Many times after replacing parts that will cause coolant loss the system will need to run a while to get the air out of it. When you originally fill the radiator and over flow it will seem full, but with the air in the system it really isn't. Once the air bubbles out you need to add more coolant to keep the proper levels.