1. When you do get the problem solved, come back here and tell us the solution. I have the same gripe - threads often die without a verification of the resolution.
2. Do you have any reason to suspect a bad head gasket? For instance, oil in the coolant, coolant in the oil, lots of white smoke in the exhaust?
3. Check the thermostat - drop it in a pot of boiling water. It should pop wide open almost instantly.
4. Hose off the antifreeze congealed on the radiator - it's blocking airflow and reducing cooling capacity. (Probably not enough to cause the symptoms by itself, unless the entire radiator is caked in it)
5. Check for cold spots on the hot radiator. If a cross tube gets blocked, a row will be cold, and the radiator will have lost a lot of its cooling capacity.
6. The fan clutch should have more resistance while it's hot and less while it's cold. The hotter it is, the less it should slip.
7. Check the blades on the water pump. If they've corroded away, you'll have less coolant flow, which will be especially noticed at low RPMs.
He that would make his own liberty secure, must guard even his enemy from oppression; for if he violates this duty, he establishes a precedent that will reach to himself. --Thomas Paine
We work together every damn day. --Jon Stewart
Any gas can be a knockout gas, when you wrap a steel cylinder around it and beat someone with it.
Low Output 4 Cylinder Jeep Club member #188