HVAC: Need Moses to part Red Sea in my footwell

[SyHopeful]

Okay folks, I've recently wrapped up a nearly year-long repainting and body work project on my GN. Looks great, learned a lot, etc etc.

Problem is that now, when left outside in rain, my passenger front footwell floods like whoa. I'm talking standing water after maybe a day of good rain. Since the cabin air intake appears to be in the cowl on the passenger side, I think the months of dust and fine sanding residue might've clogged something up and causing this issue. Am I right? Is there a drain somewhere that is plugged up?

If so, how difficult is it to flush that sucker out?

 

[turbonut85]

There is a drain. It is a 2x3 inch rubber flapper on the bottom of the AC housing in the front. This is the best I can do to show you where it is.

 

[novaderrik]

the drain in question is buried behind the passenger side inner fender well- on my '84, you can barely see it from the top of the engine bay. i had the fender off my car this spring, so i took the oppertunity to poke a screwdriver in there and clean it out.. it had about 3" of dirt, leaves, dead bugs, and whatever other kinds of debris accumulated in there since late '83.
once i dug all the crap out of there and flushed it with the garden hose, i get no water under the dash no matter how much water i dump down there.

 

[Topjimmy]

As these guys said, check the drain first. Debris or a rotted rubber seal on the flapper door are fairly common.
The 2-piece heater box flange may be a suspect also.

Good Luck - Jimmy.

 

[challengermike]

Also you may want to wrap the computer with plastic untill you get it fixed.Mine shorted out because of water getting in.Then the car wouldnt run.

 

[novaderrik]

Also you may want to wrap the computer with plastic untill you get it fixed.Mine shorted out because of water getting in.Then the car wouldnt run.

on mine, the water actually corroded the pin in the ecm where the orange power wire plugs in to the point where the pin broke off- it would make contact and run fine, but die at random intervals. then it might start back up, or not start up at all. i noticed the missing pin in the ecm when i decided to check the connections.
i wasn't angry or anything- it gave me the perfect excuse to upgrade to an 87 ecm and turbotweak chip.
as i pointed out in my last post, i cleared the drain, and now no water gets in there at all.

 

[SyHopeful]

Thanks very much, guys! I'll poke around there and try to find it. Fortunately my GN has been in a garage most of the time and when its outside I had some microfiber towels i used to remove the standing water, so the ECM should be okay. I'll check just to be sure. Very very grateful.

 

[SyHopeful]

Also, is the drain flap accessible without removing the fender or inner fender?

 

[aminga]

Also, is the drain flap accessible without removing the fender or inner fender?

Just reach down under the heater box and feel for it.

 

[SyHopeful]

UPDATE!

The vent was not the source of the leak, its around the box itself at the firewall. However, we're having a hell of a time removing the heater box. We've pulled the entire front clip off and are now having trouble getting the dash off.

Anybody have a surefire way of getting the heater box out? Pics are a plus

I'm tired of people nagging me to bring the GN out!

 

[SyHopeful]

Whoops

 

[V8Assassin]

Make sure you have ALL the bolts out (they can hide pretty far down), there is nothing hanging from the interior and QUIT BEING SO GENTLE WITH IT!

 

[SyHopeful]

Make sure you have ALL the bolts out (they can hide pretty far down), there is nothing hanging from the interior and QUIT BEING SO GENTLE WITH IT!

Should I not worry about breaking things? 23 years of being in the PNW makes me nervous.

 

[V8Assassin]

Should I not worry about breaking things? 23 years of being in the PNW makes me nervous.

Are you planning on putting it back in?

 

[SyHopeful]

Are you planning on putting it back in?

yeah i'm kind of fond of it.

 

[mygn276]

Why are you taking it out? Its probably leaking around the top lid where i seals to the fire wall. Just remove the top and reseal.

 

[V8Assassin]

yeah i'm kind of fond of it.

Well that's a horse of a different color :biggrin:

 

[SyHopeful]

Well that's a horse of a different color :biggrin:

lol

Finally got that bitch out. Anybody know the part# for the gasket that seals the heater box to the firewall?