So i've been having overheating issues so i replaced my thermostat and water pump. Now after filling the system up again it seems the coolant isn't moving through the system unless i rev it up (This problem existed even with the old water pump and thermostat). It will sit and over heat, the coolant in the radiator starts smoking and bubbles out of the radiator. Please help, lost on where to go with this.

 

If it is smoking and bubbles my guess may be you have a cracked head or bad gasket that is allowing the HOT exhaust gases in the coolant.