royta

I decided that I was going to vacuum and shampoo the carpet in my truck today. I bought the truck used and I needed to get the previous owner's spilled drinks off the carpet. I pulled the seats, the shifter housing, and the plastic trim that surrounds the carpet. I then noticed that it was wet under the passenger seat of the carpet. I went ahead and pulled the carpet out so I could dry out the insulation. I also noticed the foam backed rubber behind the dash is wet on the underside right below the HVAC housing. I pulled the HVAC Blower Motor and propped up the foam backed rubber so the foam would dry out. I have determined the leak is coming from the outside of the vehicle. There is a drain in the HVAC Housing located under the A/C Evaporator that exits through the firewall. You can see the tube sticking out of the firewall right below the A/C Accumulator. I used a garden hose to spray water on the outside of the firewall where the tube sticks through and sure enough, water runs out under the foam backed rubber that is behind the dash. I am assuming there is some kind of spongy seal sandwiched between the HVAC Housing and the inside of the firewall.

I certainly don't want to remove the HVAC Housing in order to fix the leak. I am going to attempt to put silicone caulk around the drain tube on the outside of the firewall.

Has anybody else had a leak at that location? Any suggestions on what type of silicone caulk to use?

CarlJensen

Plenty of leaks there. The water feeds back from the drain through the firewall and onto floor. Seal with any good sealant and add a length of tubing to drain leading water down and away from the drain feed through. Mine just leads down and back to inside the frame rail , where I fastened it with a zip tie.

royta

Thanks for the idea of lengthening the tube with some hose.

NGAK12

Mine had the drain tube cloggged up. I put a coat hanger into the end from the engine bay and fished around carefully to remove old leaves & stuff that had it clogged. Lots of water came out. A few months later the heater control wouldn't work. Turns out there is an electrical controler that moves the flap in the box. The water had killed it. It was a Lucas brand part, made in China. Amazing it ever worked.

justme-

yeah- most common cause for the peeing on the carpet thing is a clogged drain outlet- wasps (like mud daubers), spiders, leaves... lots of things can build up and cause it to clog.