I have a 1978 ranchero GT, it has a leak under the dash above the heater I can't seem to find out where it is coming from.

 

>I have a 1978 ranchero GT, it has a leak under the dash
>above the heater I can't seem to find out where it is coming
>from.

What kind of leak - vaccuum or coolant? When you say above the heater - do you mean above the controls, the vent, or the heater core?

 

It's leaks when it rains out it seem to be coming in through the freash air vent above the heater.

 

>It's leaks when it rains out it seem to be coming in through
>the freash air vent above the heater.

Well - I don't have an answer for you (but that never stops me from posting!). One can assume that the intended design prevents a leak - so something unintended has happened. I presume that something has either cracked or corroded. I would check the bottom seal of the windshield first - it may be leaking and then the leaked water is following the air vent. Next possibility is the air vent itself has a leak near the windshield. You might need to tear things apart a bit and use a hose to track this down. Please do post what you find...

 

[updated:LAST EDITED ON 17-Jul-02 AT 07:30 PM (EST)]>Well - I don't have an answer for you (but that never stops
>me from posting!).



same here! my 1st guess would be (as mentioned above) the windshield seal or where the "box" attaches to the firewall, since it does it when it rains. in either case it would be rainwater coming in.

2nd guess would be... condensation? maybe when it rains the humidity or whatever is such that condensation forms on the ducting to the A/C vents and then drips down.

unless... do you use the heater when it rains? a bad heater leak will always leak (pressure is the same, heater on or off), but there could be a slight one that only leaks when it has the flow through it. i had some kind of car that did that once, a long, long time ago...

 

Check the cavity just below the windshield that houses the wipers' arms that attach to the wiper motor, leaves and all kinds of crap lay in this cavity causing a rust-through problem. It's easy to check just pull off the plastic screens and with a wet/dry vac vacuum all the debris that resides in there. Hopefully you will find the source of your leak.

Todd
BB79RANCH

 

> Check the cavity just below the windshield that houses the
>wipers' arms that attach to the wiper motor, leaves and all
>kinds of crap lay in this cavity causing a rust-through
>problem. It's easy to check just pull off the plastic
>screens and with a wet/dry vac vacuum all the debris that
>resides in there. Hopefully you will find the source of your
>leak.
>
> Todd
> BB79RANCH

My Ranchero don't seem to have the plastic screen, it look like someone put some metal over the cavity, I tried to seal the metal, it slowed the leak down but it still leakes a bit when it rains hard. I try and see if I can get the metal off and see what under it. thanks for you help.

 

that's weird - i wonder if the guy sealed that off BECAUSE it was leaking somewhere in there?

i was under the impression that the air that blows out the heat, vent & A/C came from up inside there - anybody know?

 

thats where it comes from. probably going to find a baddly rusted seam in the firewall under there. roayle pain in the butt to fix too. gotta keep them cleaned out or park inside all the time. some one probably worked on it and left the screens off at one time, very bad idea.