I would suggest that you test your radiator cap as it may not be operating properly.

Unfortunately you may have another problem and that is that you may have a cracked head or leaking head gasket. In this case the combustion gas in the cylinder is leaking into the water jacket and pressuring the cooling system up. This causes the coolant to be blown into the overflow tank. Because of the process that occurs, the coolant from the overflow tank is not pulled back into the radiator as the engine cools as it should be. The fact that your overflow tank is empty at times is another possible indicator of this. If you drive long enough, the combustion gas will eventually blow the overflow tank dry. You can get a tester to check for combustion gas in the radiator.

If this leak exists you won't often see any antifreeze in the combustion chamber as it is the cylinder compression that forces the gas into the cooling system by higher pressure. Generally there is not enough pressure in the cooling system to force coolant the other way.

I currently have this problem with my BII 2.9 V6 and I have been trying to deny it but I know I am going to have to overhaul the engine. I have the same problem with my 1991 Ranger 3.0 V6 as well but it has almost 400K miles on it. It blows the coolant out big time though.