AC box leaking condensate, help... complex.

[euroZ06]

Hi all,

For the past two years i've been trying to fix my condensate issue. Quick back story: the heater/AC box looks fully restored (car was restored a few years ago, prior to me purchasing it). AC works, however, the condensate doesn't always drain out the tubes.

Sometimes, it does drain though, sometimes out of one tube, sometimes out of another (but when driving it always drains inside, not sure if it is draining outside). I've tried testing it today. Parked on almost even ground, from a cold start, i.e. there was no condensate in the tray when I started the experiment, after a few minutes it started pouring out of both tubes, more so on the passenger side. Then I parked it straight down on a steep downslope, and it was pouring out of both of them, however, the driver side was also pouring inside the car (more into the car, than through the tube). Then I parked it sideways, with the passenger side downslope, and it was pouring out of the drain tube no problem. Then I parked it with the driver's side downslope, and it was pouring out of both the driver's side drain and inside the car. Then I started driving straight and it was pouring inside the car from both the passenger side and from the drivers side.

I have blown condensed air through the holes, and poked with coat hanger, and it doesn't appear that anything is blocking them and has no effect.

I've looked under the dash, and it appears that the drain tubes are slightly bent upward   I'm not sure if its a natural bend, or was bent during the rebuild (it is so slight, that it is not readily apparent). I have a strong suspicion that because of this the condensate doesn't drain properly. Does this sound like a good theory? so maybe when the car is parked on a small slope, it drains out correctly, but because the tray and the drain tube is out of alignment, when the tray gets full, its easier for it to just spills out all over? or perhaps both drain tubes are bent upward a bit, with the drivers side being bent more so, so when the tray fills up, it will try to go out the passenger side, but on the drivers side its a 50/50? and when you are driving, the inertia pushes the condensate slightly backwards making it spill out?

So if it is a sound theory, I don't really see a good way to bend them back down, because there is not much space where the firewall holes are. The drain tubes sit towards the bottom of the firewall hole. Maybe when they were installing the box, that was the issue, that it was installing too low to fit the tubes into the firewall holes, so they just bent them up a bit?

Is it possible that the heater/ac box is sitting too low/sagging on the interior side (vs the firewall side)? is there a way to raise it up to get it level or higher (I can't tell if its level or not)?

Could it be that the tray inside the box is not sitting correctly? if I understand correctly, there are 4 bolts that hold the evaporator inside the box with the tray attached on the bottom. Could it be that some screws are not on correctly/broke/unscrewed? is there a way to fix that/check that?

A friend of mine suggested 2 options: 1. Drill a hole in the firewall below the stock hole, and try to bend the tubes down. 2. Put in small hoses inside the drain tubes, and bring them down below the drain tray (perhaps the gravity would overcome the bend?).

Any advice and your thoughts on this are appreciated.

p.s. I live in an apartment building, with large garage, and I am not allowed to do any work inside there (they are very strict). On top of that, I live in Miami, so its 90F everyday. I went to a shop, and to remove the box and fix whatever is wrong is $750, but they won't even touch it till November, cause they are busy.  So I'm looking for creative ideas, vs "take the box out."

[AKcharger]

 

Watching too

[gtx6970]

if it leaks inside the car there is a problem with the condensation tray below the evaporator inside the box.
In all honesty, the only right way to fix it is remove and dis-assemble the box

[AKcharger]

Can you get the box out without pulling the dash?

[jlatessa]

Pretty sure on most B bodies you can pull the box alone.

What year??
do you have a FSM? You'll need one for a lot of things on an older car.

Joe

[A383Wing]

I thought there was supposed to be a 90* hose on the drain tube inside the engine compartment so the radiator fan and car movement would not force air back into the heater box via that drain tube?

I have them on my AC cars

Bryan

[ODZKing]

  my 73 similar issue but only when it's extremely humid.

[euroZ06]

thank you for replies.

i have since placed a hose on the passenger side tube (only had one), and it doesn't change anything I just think that if the tube's opening is on the same level as the top of the tray, gravity takes effect and it just pours out of the tray, instead of the tube... i mean, the whole system looks brand new, and when the car is parked at certain angle, water does come out of both tubes.

how do I adjust the position of the whole system, to raise it up a bit? I feel like if i can raise it, then maybe i can bend the tube down a bit.

Would it be a bad idea to just drill a hole in the firewall, right below the current hole, and just bend the tube down? then maybe use a rubber plug?

Again, I was quoted 750 for the removal of the box, and i can't do it in my public garage.

[euroZ06]

Im going to post this in hte main AC thread, but I'll also ask here:

I see in the rebuild thread that the drain tubes are metal, but mine are copper. and I also see some rubber around the tubes, so does that mean I have two tubes (copper over metal)? Maybe the tubes are not connected well, so when it flows into the copper tube, it spills and just goes elsewhere....?

[ODZKing]

It is interesting that you mention about the tubes not being straight, mine seem tilted as well. And as yours are, I have the curved hoses on both of mine and didn't help.
Now having said all that my car sat very low and last fall just before winter I had the rear springs re-arched. The car now sits up in the back, however with all that is going on this summer I have not had an opportunity to even take the car out on a hot day. again it is only when it is extremely humid ... so I guess it will now have to wait until next summer to see. 

[gtx6970]

There are  foam seals inside the box where the tubes protrude thru, there is also foam seals to seal said tubes to the firewall where they pass thru

Said tubes are soldered to the tray under the evaporator core to prevent condensation leaks inside the car. If you have a leak inside the car , you have an issue inside the box

[euroZ06]

There are  foam seals inside the box where the tubes protrude thru, there is also foam seals to seal said tubes to the firewall where they pass thru

Said tubes are soldered to the tray under the evaporator core to prevent condensation leaks inside the car. If you have a leak inside the car , you have an issue inside the box

The condensate leaks out opposite of where the tubes are. If I'm on a slight decline (with nose pointing down), the condensate goes out the tubes as it should. i need to somehow raise the back of the assembly (part facing the interior of the car) up a bit. I can't figure out how to do it.