The saga continues. I pulled a heater hose to allow the system to burb. Didn't hear any air, but the coolant flowed at the hose when I removed it. This was with the radiator cap off. Now here is what happened next. I paid a little closer attention to what was going on this time. I watched the gauge. No coolant coming out the overflow. The upper tank stayed cold to the touch until the gauge hit about 180 - 200 degrees. When the thermostat opened, the upper hose was hot and the tank got hot, but as soon as the coolant hit the radiator through the upper hose, it went right out through the overflow. I don't know if this means the thermostat is defective and not opening early enough, if the thermostat is too high of a temp unit for the truck, if there is still air in the system or what. It wouldn't seem like the fan is the culprit, but I don't know much about cooling systems. The fan is putting out really good air, but it all seems backwards to me. The flat surface of the fan faces the radiator, but the way it is designed, it can't be turned the other way. Seems like all of the air flow would be going back toward the engine and not toward the radiator to cool it. Anyway, hopefully this additional information will shed some light on the fix for it. Thanks guys. Jim, I think you are right about the cap needing to be off to burp the system.
