I just bought a 1994 XJS Convertible. I am almost certain that my A/C evaporator drainage must be plugged. I have run the A/C and even on the hottest days there is no moisture leaking under the car and the front footwells and the floor mats are soaked. Is there an easy way to unplugged the drainage without removing the whole dash? Can I get to the drain line(s) from underneath the car and unplug them with fishing a line up or with water pressure? Got any drawings of what I'm dealing with? I don't want to pierce the evaporator, of course. I realized that would be an expensive mistake. Thanks for your help and advice.
Submitted by NE52-32043 on Mon, 08/09/2004 - 10:29
From underneath the car, you should see two rubber hoses coming down, one on either side of the transmission. It's pretty common for these to get plugged up (spiders love to nest in them). You can try snaking something up there, but be careful not to rip the hose. As an alternative, you can try blowing air up the hose. Again, be careful not to use too high a pressure so you don't blow a hole in the hose. I wouldn't use water pressure -- you don't want to spray water around inside the AC unit if you can avoid it.
The only other alternative is to try to get to it from inside the car. I'm not familiar with the later XJS's, but on my old '89, they came off the bottom, up under the dash, and you could access them from underneath if you pulled back the carpet, if I'm remembering correctly. It's been a long time.
Either way, expect a rush of water (and possibly other junk) once you've broken the clog.
Steve Weinstein, JTC-NJ
'70 XKE FHC