Hi all,

I have a couple of questions regarding internal water leaks on my 1966 GT fastback.

First, I would like to mention that the interior of the car is fully removed, so this may be an issue of missing drain tubes, but then again maybe not. Anyways, I noticed water running from the bottom of the fresh air vents in the back seat. More specifically, the water was coming from metal tubes at the bottom front of the inside vent assembly. Should there be drain tubes connected to these. If so, where does the opposite end of the tube connect for drainage to the outside....I can't seem to find any on the rear quarter panel.


My second leak is more of a concern... possibly the dreaded cowl leak. Strange, though since I dropped a water can ( about 2-3 gallons) of liquid down the cowl on a level surface.....no leaks. However, same procedure on an inclined driveway resulted in drips coming from a circular plastic object (air vent) on the far left of the driver side.


Any suggestions??????

 

The air vent on the drivers side is connected to the cowl. If it leaked from the vent it doesn't mean the cowl is rusted through.
It could be that the drain holes are plugged up and the water overflowed into the vent.
You need to verify that water is coming out of the drivers side drain hole.
Since the interior is out I would pull the vent, and inspect the metal 'tube' that extends up into the cowl. Then pour some water in the cowl, or use a garden hose and see if the water is overflowing into the vent or leaking through the metal.
They sell plastic fixes for that problem.

 

You can see the rubber drain hose in this photo

http://midnightdsigns.com/Mustang/Wi...tery%20003.jpg

If the rust is not significant, you can wirebrush your cowl vents, coat with a rust encapsulator, and install the plastic top hats.

 

Thanks for the suggestions. What is the best way to remove the debris after wire brushing the cowl?

 

The rear vents have a catch channel under each vent that has a metal tube about 3/4" in diameter and about an inch long as a drain. A hose connects to this drain and travels down to the hole into the rocker panel. If you look under the rocker from the outside, you will see a small slit in the bottom of the rocker facing the rear. This is where that water should drain out of the car. Of course, it gets clogged with debrise and the rocker rots!

Unfortunately, it sounds like you have a cowl leak in the front.