How to Fill a Radiator With Coolant

The coolant for most radiators is a half and half mix of water and radiator fluid. Find out how many gallons the radiator takes to fill and then proceed with filling it with the fresh radiator fluid mix. On the top or the side of the radiator is a label that has all of the information as to what type of radiator fluid that particular radiator takes and how much. If the label is missing, check with the auto parts store for the information when you purchase the coolant.

Things You'll Need

  • Five gallon bucket
  • Radiator fluid
  • Water
  • Funnel
  • Place the five gallon bucket on a flat clean surface. Mix the radiator fluid and water together according to how many gallons the radiator holds. Make sure that you mix the fluid and water in a 50-50 ratio.

  • Remove the cap from the top of the radiator by twisting the cap and pulling it from the radiator. Insert the funnel into the radiator.

  • Pour the radiator fluid mixture into the radiator through the funnel slowly until the radiator is full. Replace the cap to the top of the radiator.