Honda 1997 Civic Sedan Online Reference Owner's Manual page 133

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.
Maintenance
1. Slide the heater temperature
control lever to maximum heat.
Open the hood. Make sure the
engine and radiator are cool to the
touch.
2. Remove the radiator cap.
DRAIN PLUG
3. Loosen the drain plug on the
bottom of the radiator. The
coolant will come out through the
hole in the splash cover.