Coolant Leak in Heater Box??

[mayoungblut]

I have a couple 1990 560SECs--one with 70K mile which is experiencing a coolant leak. The coolant is coming out of the drain tube located in the passenger side front wheel well. I ASSUME IT IS A DRAIN TUBE FOR THE HEATER (CORE) BOX. There is no other sign of coolant leaking anywhere on the car--engine bay hoses, firewall hoses/valves/fittings. The leak is occuring somewhere internally and escaping from the drain tube. Has the heater core failed? Hose or valve? Before I invest a day taking the car a part to get to the heater box, does anyone have any ideas what the problem might be????? Thanks

[Don350SDL]

Before I invest a day taking the car apart...
It might be more than a day if you've never done it before.
Most likely it is the heater core - you should be able to smell coolant coming from the heat vents (turn the heat to max). There's not much else in there, the hoses connect outside the box...
Before it all comes apart, with an hour's effort you can get a light & mirror up there (go from the passenger side) and maybe even get to see it.
Good luck, I do not envy you the job (but I do the cars!)

Don