This Is A Bottle Of Radiator And Heater Core Flush & Lubricant. If You Are Replacing Your Coolant Or Antifreeze On Your Jeep We Highly Recommend Using This Johnsen's Brand Radiator Flush. Each Bottle Contains Safe Chemicals For Your Radiator & Heater Core That Not Only Help Remove Residue, Scale & Corrosion Deposits But Keep Your Water Pump .... - Yes, Radiator Flushing can unclog the heater core by removing the rust which passes through the heater core. Q: Can You Drive With A Clogged Heater Core? - Driving with a clogged heater core can lead to an increase in the temperature of the engine and damage engine components because it reduces coolant circulation.