Not your average leak from the a/c drain

Towards the end of last summer I noticed water collecting under the floor mat on the passenger side of my Tacoma. Figuring it was a clogged a/c drain line, I disconnected the line from the evaporator housing under the dashboard and blew it out with some compressed air. I figured that would solve the problem and I didn't notice any more water collecting on the passenger floor for the rest of the fall/winter. Of course once you get into fall around here you don't use the a/c much until the end of the next spring.

To make a long story short, the water is back, and there appears to be a crack in the bottom of the a/c evaporator housing where the rubber hose connects to the housing. It doesn't appear to be the hose connection itself, but rather a crack where the nipple is formed into the plastic evaporator housing. I have to find my inspection mirror to confirm, but it seems like I may need to try and seal up the crack or ultimately replace the bottom of the housing because I don't think the drain nipple can be removed from the housing.

Has anyone ever encountered this situation? How hard would it be to replace the bottom of the plastic housing? Can I do it without removing the dashboard? I had to replace the heater core in my Rav4 years ago and that was a huge pain in the ass. I may try to fix it with some sealant or plastic weld but the leak is coming from a very hard to access area.

 

I would try to repair it with some JBWeld if you can get to it.

 

actually the best thing for this is Lexel,

since lexel can be applied to wet stuff it will still stick perfectly and seal that right up
and it won't harm the underlying plastic.

 

Remember, this is not pressurized, it's only a drain. So as 127.0.0.1 says, if you get the right product in the right place, it should be just fine.

 

Yeah that's what I was thinking about using because I already have a tube of Lexel from another project.

It's slightly pressurized because it's on the output side of the HVAC blower. If you detach the hose you can feel air blowing out of the housing along with the condensate.

 

Well after a few months of driving with minimal a/c use I finally found the time to try and fix the leak yesterday. I tried Lexel which I thought would work but it didn't stick to the plastic very well even though it was dry when I applied it. I thought about using another type of sealant made for plastic but the leak is in such a tight spot I knew I would make a huge mess trying to apply it and figured it would still leak. I had some plumber's putty on hand so I decided to shove a bunch of putty around the hose and the cracked area to see if that made a difference. Don't get me wrong, I know it wasn't the right thing to use but I was frustrated and just said "f*ck it".

I let it sit overnight so I haven't verified the solution yet. With my luck it's probably still going to leak, but if it slows the leak down a bit I can wait until next season when I might have the extra $1000 to tear the dashboard apart and get the damn thing fixed. If the plumber's putty doesn't work I may get some special putty that bonds to plastic because putty is much easier to apply to the area in question than liquid sealant.

 

Good luck and hope it works for you. I need help with one step prior to fixing the leak.

After a long road trip a few weeks ago through the heat and humidity we've all been having I noticed a small amount of liquid on the front of the passenger floor mat. Only about one ounce or so every two or three hours when I stopped for gas. Small amount but shouldn't be leaking at all.

I think I have the same problem as the OP but I can't access the drain tube inside the cabin. Seems that there's a bunch of stuff keeping me from accessing it under the glove box on my '15. I did take a shop vac to the drain tube in the engine compartment trying to free any blockage that way. But I'd still like to inspect where the hose attaches inside the cabin to make sure everything is in place there.

Any insight would be great!

 

Op, I realize it's in a tight spot, but since your having a hard time getting a sealant to stick, can you get something in there to rough up the surface a bit? Wrap some sandpaper on a stick or something? And since the Lexel didn't work, maybe try JB Weld Marine, it's for wet locations specifically. It's been holding up two years on my pool skimmer.

 

Maybe try some Fiberglass Resin, it would work if you can get a paint brush up in the area and some fiberglass cloth would be added reinforcement if you can access it.