I've been fighting leaks and wet carpets since I bought my rig years ago!
I've had the interior/carpets out a couple times. New sun roof gasket. Tried a number of things that never seemed to work. We had a lot of rain this summer, esp in July. This fall I had an inch of water standing on the floor when I removed the carpeting! Carpeting was so heavy I could hardly lift it. I had to soak it in soapy water to de-mold it! If finally decided to get REAL and get to the bottom of things, stop chipping around the edges. I'm going to do a whole write-up on this soon....but below are the issues I had and how I resolved the problems. Your rig might have some of these issues, or none at all.
Basically there were multiple things going on with my H3:
1) Cracked/leaking Roof Seam Sealer: The seam sealer along the edges of the roof (under the roof plastic) had cracked from age, being dry, etc. It's not uncommon if you read back old posts. There was an exposed small 'hole' on the driver's front...which water was for sure coming in. Also along the rear of the roof back by the rear door was also leaking a little it looks like. I re-seam-sealed those areas with some urethan caulk..(about the same color as my rig).
2) The drain tubes in mine have been dirty, but not lately. Even with the 'fingers' still in. Sometimes they would be dirty, sometimes not. But ultimately the tubes weren't where my leaks were. I *thought* they were ....but in my case the water was coming in other areas (keep reading). I know a lot of owners, that is a leak point. That's an easy fix.
3) Windshiled Pinch Weld Rust: Turns out there was rust on the windshield pinch weld (under the urethane adhesive), and doing a water test I could clearly see water dripping down inside the top of the pinch weld about in the center (then running across the headliner over to the edge and down onto the floor. I had the interor out and did a water test.
4) Loose windshield: In addition to the rust on the pinch weld, my tk's windshield was also LOOSE on the driver's side upper corner. I just happened to see the glass 'move' when I was trying to address the roof seam-sealing. The windshield shouldn't move at ALL!! Maybe off-roading loosened it up?? Or a piss-poor install job in the past??
Ultimately I pulled the windshield and sure enough there was significant rust under the urethane gasket material at a couple places, particularly in the center. How can that happen? When the windshield is removed, if the pinch weld area gets scratched up (by a remover's tools), rust can develop there ..esp in the rust belt areas.
I removed the urethane adhesive, masked off the vehicle and sandblasted the pinch weld area by the roof (pic below). Then treated the pinch weld area with some old-school Zinc Chromate primer (the REAL stuff that's been EPA'd out!). That's the stuff that doesn't let metal rust when ya put it on.
5) Roof Paint: The roof paint was always sucky (flaking clear, chips, dull), so I stripped the paint, fixed any chips around the sunroof gasket (another source of leaks), and repainted the roof. I wetsanded the entire roof with 320 grit (wet/dry) on a mud hog which cut the work down significantly ...then ran over it again with 400# (wet) on a DA. A coat of sealer and resprayed the roof base/clear ...as well as painted the sandblasted & primed windshield pinch weld area.
I installed a new windshield and currently I see no leaks, doing multiple water-test and high-pressure sprays.
6) Painted the plastics: The plastics along the windshield up across the top and the back looked terrible. Gray/white... Like a lot of hummer plastics ..from the sun. Today I repainted all those plastics, and the paint is curing right now as I type. They look like new!!! Eventually I'll repaint the rest of the plastics around the bumpers, mud flaps, etc. Probably not till next spring though.
7) CB Antenna Wire??? Next, I need to decide if I want to drill a hole in the roof for the CB antenna wire... or not. Getting a water-tight seal isn't my concern. Just, do I want to put the extra work into it? Now would be a great time since I've got the headliner dropped and interior pretty much out. My wife doesn't like how crappy the antenna wire looks running it along the outside rear door. So that's next on the list.
The point is...there's a lot of potential leak points on an older H3, not just the grommets. If it's been an ongoing issue, you might want to pull the interior, pull out the carpets and let them dry out (they'll never dry out on their own, till the floor rots out!!). Clean the grommets, drop the front of the headliner, and do a comprehensive water test. I wish I would have done that a few yrs ago. Obviously I've done a lot of work to it lately, but all of those things needed to be done anyway. The glass was ok, but not great. Roof paint sucked and the plastics looked terrible. Again, I'll do a more comprehensive write-up, but try looking things over carefully so you get it all the first time. If you're lucky, your issues is just the drains.
