I talked with Jai (redwing) last night and she brought up an odd thing that happened in her 76 280. When she was going around a left hand sweeper turn at a bit more than cruising speed about a half cup of noticeably cold? (not tepid) water landed on top of her right foot. The odd thing is she thinks the water came from the right side, as in from behind the radio. She says the heater core has been removed to make room for the AC. She also says that she has a shut off valve plumbed into the heater hoses under the hood.  She states @siteunseen has a picture of her set up. The question is in two parts. First question is where is the source of the water. Second question is how does water end up coming from the right side while turning left. Centrifugal force should have moved any water to the right side of the car not to the left. 

was it raining? was the AC on?

 I'll find out and report back.

this is the car with the after market AC? its hot and humid this time of year in Georgia, I was thinking condensate somehow accumulating. Would account for it feeling cold. Maybe ask her if the AC is working and if it is, does she see a puddle of water under the car when stopped but AC on?

I had the same problem but it was related to rain, turned out to be a poorly sealing window gasket. The fix was to seal with some butyl (the gasket was fairly new, just did not seal well). The FSM calls for sealing as well, but there was no sealant used (I could not see any evidence of it).

Edited August 5, 20195 yr by Dave WM

 Jai says it wasn't raining and she rarely drives it in the rain. The AC was on at the time. I'll ask about the puddle.

Ya, sounds like A/C condensate...

she will have to get some one to look it over closely, could be hard to see, esp since aftermarket and can't help since I don't know the installation. BUT most likely a drain line has popped off the evap housing OR the drain tube is blocked (pinched). Best bet would be to take it to the guy that did the install, as he should know the drain details.

Discounting the idea its coolant since its not warm. could do a taste test if not sure.

Edited August 5, 20195 yr by Dave WM

 Jai says she's seen a puddle under the car in the past. I'll tell her about the drain line. That sounds like the source of the water. Thanks