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Possible solutions for water leaks on passenger side


JTrigg

Member
Joined
Jan 5, 2020
Messages
49
Location
Texas
Specific to a 99 Wrangler Sport with AC, 4.0. But probably carryover to other years and models....

All the things I addressed to finally get it stopped, some likely not the problem, but all were potentially issues and I am sure there was a combo assault, as I got the leaking from one area to stop, but not until I addressed the last issue has it (so far) stopped altogether...

Items needed / used (other than tools): FlexSeal in the spray can, and any basic general purpose adhesive in a tube. The adhesive is used as a caulking material....

1. Add a hose to your AC drain vent, which is currently just a short stub poking out of firewall under on the passenger side. The theory was in some conditions rain, or surface water, could blow back up into it, or wind could push the condensate back in.

The following issues address the foam insulation material around these parts and areas, which on a 1999 jeep is worn, brittle, and flaking away....

2. Flex seal the entire area where the AC tubing enters the cab from the firewall. That is foam and has likely pulled away from the tubing.

3. The cabin air intake is located under the plate between windshield and hood. It is raised, so water normally won't enter it unless the area is full of leaves and debris (which it may be). However, 3 screws hold down the plastic housing, and there is a gap between it, and the "funnel" into the ventilation system. It is filled with the foam, most likely crumbling, so put the adhesive in, or otherwise caulk up the gap.

4. Remove the battery, and look under it to the fan motor housing. It sits in a little concave area with, again, some foam insulation around it. Flex seal the area.

If you look at my past postings, and probably elsewhere on this forum, you can find a step by step to removing the cover plate between hood and windshield....
 

Bas-NL

Member
Joined
Apr 27, 2020
Messages
91
Location
Veldhoven - Netherlands
a couple a months ago i did almost the same thing exept removing the cover plate . at mine tj the foam insulation was crumbling. i replaced it with flex seal.

maybe i will remove the cover plate(y). thanks for your writing.
 

isaac2098

TJ Enthusiast
Supporting Member
Joined
Dec 28, 2018
Messages
161
Location
Connecticut
I removed the cowl a few weeks ago after I woke up to some puddles on my passenger floor mat and found it to be pretty clean BUT the foam gasket around the air intake was a little damp.

I took that opportunity to removed the air intake which is just held in by 3 screws, let it dry off after I cleaned all the dirt and dust off of it, reinstalled with very good waterproof silicone sealant and haven't had any issues again. I'll have to check under the battery and the lines where the AC tubes come in. (y)
 

KingCarGuyZ

TJ Addict
Joined
Feb 26, 2020
Messages
1,150
Location
Dallas, TX
Well I cleaned the vent and re sealed the cabin air intake, see if that fixes the problem. I’ll probably also throw a hose on the A/C drain and look at the foam around it. Just have to wait for it to rain again down here.
Thanks for the thread, really useful.
 
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Jodh

TJ Enthusiast
Joined
Feb 18, 2019
Messages
145
Location
Dallas
When I had my 99 it leaked back into the passenger floorboard. Took it back to the dealer and they said nothing was wrong with it. Had a friend look at it and he immediately noticed the condensation drain was level coming out of the firewall. Went to the auto parts store bought a short 5/8 elbow and a hose clamp and never had a wet floorboard again. The 2000 or 01 have an elbow.
 

Lowcountryearl

TJ Enthusiast
Joined
Jul 20, 2020
Messages
100
Location
Charleston SC
Same here, very humid in the Carolina's, the foam around the AC drain was crumbling and the AC was pumping out a lot of water from the humidity. At highway speeds the water blew back down the short ac drain into the cab. Put the 90 degree elbow and an extension pipe, never had the issue again, never sealed the foam around the AC drain
 

Hickey129

Member
Supporting Member
Joined
Jul 13, 2020
Messages
33
Location
Tennessee
I used 3/4" pvc 90° elbow pipe fitting on the ac drain sealed it to the firewall with gasket maker ,all good ever since 👍
 

Moab

TJ Addict
Supporting Member
Joined
Dec 15, 2018
Messages
2,221
Location
El Segundo, California
I'm not gonna post the old "This thread is useless without pics." emoji (or whatever u call it). But pics would make this most even better.

Its an excellent post though. As Im chasing a similar leak.