The need to drain the coolant from your Mazda’s radiator often comes about during a cooling system repair. A failed thermostat, heater core or ruptured radiator hose all require that you drain the coolant to some degree. Mazda recommends that you change the coolant after the first 60,000 miles on most all of their vehicles, except the models that use FL22 coolant. With a few common tools and a well-ventilated working area, you can drain the coolant yourself. You should expect to spend, from start to finish, 35 minutes performing the job.
Raise and safely support the hood of your Mazda. Remove the radiator cap and store it in a safe location to prevent it from dropping into the engine compartment. Peer down at the back of the radiator and locate its drain plug. The plug mounts on the right side, if you’re standing in front of the radiator. The drain plug also has a clear tube connected to it, which measures 3 to 4 inches in length.
Apply your vehicle's emergency brake and block both of the rear tires. Raise the vehicle 14 inches on the driver’s side, using a hydraulic jack. Set a jack stand beneath the frame rail for added support.
Slide under the vehicle at the corner of the bumper, on the driver’s side, so that you’re looking at the bottom of the radiator vertically. On the left corner of the radiator, you should see a small square access door. Pop the door open from the right side, using a flat-head screwdriver. Just beneath the door, you will see the radiator’s drain plug.
Reach up into the access door with a pair of pliers and turn the drain plug a quarter-turn counterclockwise--just enough to loosen it. Set your coolant drain pan beneath the access door, in line with the tube at the bottom of the drain plug. Turn the drain plug by hand, counterclockwise, until the coolant starts to steadily come out of the clear tube. The coolant should take 20 to 25 minutes to completely drain from the radiator.
Close the drain plug by turning it by hand, clockwise, until snug. Tighten the plug an extra quarter-turn clockwise with the pliers, then shut the access door. Remove the jack stand and lower your Mazda back down to the ground safely. Remove both wheel blocks from behind the back tires, then release the emergency brake.
