Large amounts of water is leaking from the evaporator drain hose located under the hood on the firewall. How do you repair this?
Heater core? on 1999 Ford Taurus
Large amounts of water -- like quarts or gallons? Is it coolant or water?
What I mean by lots of water is all the coolant will be gone out of the radiator and the engine and the engine will be running hot and then I fill it back up with water and it all leaks out again within one day.
OK. What makes you think it is an evaporator drain hose? I'm thinking you may have a heater hose leaking, perhaps one to the heater core. If this is the case, it's an easy fix - replace the hose. The evaporator does not have a drain hose, there is merely a drain hole underneath the vehicle at the bottom of the evaporator box.
Because that's what it says it is in the repair manual. There is a picture that shows it but it's not really a hose though. It has an opening that is under the hood on the firewall. It looks like just the evaporator drain.