1999 Honda Civic Owner's Manual - Page 176

Cooling System Replacing Engine Coolant The cooling system should be completely drained and refilled with new coolant according to the time and distance recommendations in the maintenance schedule. Only use Genuine Honda Antifreeze/Coolant. Draining the coolant requires access to the underside of the car. Unless you have the tools and knowledge, you should have this maintenance done by a skilled mechanic. 1. Turn the ignition ON (II). Turn the temperature control dial to maximum heat. Turn off the ignition and remove the key. Open the hood. Make sure the engine and radiator are cool to the touch. 2. Remove the radiator cap. 3. Loosen the drain plug on the bottom of the radiator. The coolant will come out through the hole in the splash cover. (U.S.: Si model, Canada: SiR model) Remove the drain bolt and washer from the engine block. DRAIN PLUG CONTINUED Maintenance