A/C leaking into cab

[5-O Cummins]

Seems like I got a few problems dropped on me all at once. This time I found that the A/C is leaking back into the cab. I noticed a wet brown colored spot next to the passenger seat and began to investigate. After looking, it seems that the vent tube(?) inside the engine bay is leaking back into the cab. I felt what seemed like a foam oring/seal around the tube in the engine bay and it was soaked. After I pulled the carpet up in the cab I could see that water was coming from the same area inside. Right now I soaked up as much as I could with towels and went and got some damp rid. I figured I would let it dry out for a few days and then try and silicone the tube in the engine bay and then throw some on the inside.I'm sure I'm not the first with this issue so maybe theres a different fix. I'm definitely not taking my whole dash apart though, as long as I dont have to.

[cummins2k]

When the ac system operates there will be some condensation on the evaporator that should exit a drain on the passenger side of the truck I believe. This drain is probably obstructed. Cleaning the drain and evaporator core area would be the best solution.If there is in your opinion excessive amounts of water then the core could be freezing up and later unthawing. This is usually caused by poor air flow across the evaporator or the system is low on refrigerant. However if you think the system still cools fine then the problem is almost certainly related to the drain. If you think the cooling should be better I would start with cleaning around the evaporator coil and making sure the drain is clear. Should you need to re-charge the system you can get the refrigerant at about any autoparts store even some department stores, just make sure you get a can with a gauge on it.However if the system is low chances are you have a small leak. In order to appropriately fix a leak the system should be reclaimed. Discharging R134A to the atmosphere is still considered illegal despite the fact it has less of an environmental impact as R12.

[5-O Cummins]

Nope the A/C is cold. Where the drain comes out onto the passenger side it seems to be draining fine. The issue I see is around that drain it feels almost like a foam o-ring and that is soaking up the water which is in turn slowing dripping into the cab. Maybe all that is fine and there is a restriction in the drain hose allowing it to drain back into the cab. How would I clear the drain tube out?

[MnTom]

All you probably need to do is get a shop vac and put it over the drain on the firewall. You can find it on the passenger side down near the bottom of the firewall. Put the hose over the drain and let the vac do its job to pull the gunk out of the drain.

[Mopar1973Man]

Wonderful idea...

[MarbleCrusher]

I agree with Mntom's idea, used a small shop vac on my old f-350 farm truck last summer and it fixed my clog!-Jordan-

[5-O Cummins]

Thanks, I'll try the shop vac idea. Hopefully it will clear any restrictions. The only other problem is getting the carpet to dry, it is soaked. I tried to soak up as much as I could with towels and now I got a fan setup in the cab with damp rid too.

:banghead:

--- Update to the previous post...

Just shop vac'd it and didnt see anything come out. Hopefully it may have loosened any restrictions though.

[John T]

After replacing my evaporator I had the same issue.I returned to the mechanic and he used a sealer around the drain tube. Been fine ever since.Carpet dried out fine... but Florida sun will do that.

[RJC2]

Water in the cab is hard to dry as the factory carpet has a rubber liner and it holds water under it, at least that is how my 2002 carpets are. A dehumidifier placed in the cab overnight would do alot to dry it out. I have done this many times after cleaning carpets and it really dries the thing out.It would be best to puff the carpet up as much as possible to allow the dry air to get under it.Damp rid is nothing more than calcium choride in a container with an area beneath it for the water to accumulate. It has very little capacity to dry in comparison to a dehumidifier.Also, if the water lays in there long enough it will start rusting out your floorboards and you will have a musty smell.