Okay well I got the headliner out and I have discovered a broken drain tube on the driver side up front. That's what was causing my occasional drippage.

I will fix that for sure. I think I just might fix that and put her back together. I just tested the roof for leaks and could not discover one. I know that may sound dumb to not replace and reseal everything while I'm in there. But as they say if it ain't broke. I hardly ever used the sunroofs anyway out of fear of breaking them.

I would like to know however. If there some sort of coating I could put on the back side of the headliner to keep the cloth on the inside dry in case a leak does occur?

I mean hell maybe I line the backside up with cut up clear plastic bags to potentially keep the headliner dry.

 

There's a lot to be said for leaving well alone as you say, especially when you realise that the rive-nuts, in the finish trim, can corrode to the screws and you end up pulling them out and have to try and refit them in place.

As for the 'rubber' seals I got in the habit of annually removing them, cleaning them and the frame, then, making sure the channel and rubber were dry, refitting.

The last thing I would do would be to fix the seals in with sealant because there is always the chance that you will want to clean the seals and it's a lot easier if you can take it out than have to try and clean around it.

 

7

I redid mine in Black. I like it,....side benefit was I didn't have to try to match the beige interior trim

 

Unless You stick Your hand to the glass and feel water coming from the rubber seal, LEAVE IT ALONE. If You have water coming in, its more than likely coming from the outer seal on top of the cab. Note the outer seal in nothing but a thin layer of urethane.
1. Remove the Headliner.
2. Remove the Sunroof Motor (3 screws, and disconnect the wiring (connector).
3. Cut the tubes at the closest point to the drain port. Do not try to save the hose by pulling it off the nipple. You will crack the nipple & You'll have plenty of hose length and cutting a 1" won't make it too short. If it does, get a hose connector and some hose.
4. Remove the 14 star screws holding the sunroof pan in. The Sunroof Pan should come right down. The screws closest to the drain nipples could be rusted/seized and very tough to remove. I only had 1 give me a problem.
5. Push up on the sunroof, and at this point the whole module should be free, and You can remove the sunroof and have revealed the bead of goo has completely disintegrated.
5a. Pull the Sunroof out on a angle (because the Sunroof won't come out straight up due to the track), and move to towards the rear of the vehicle, this will give the tracks clearance and the entire sunroof module is out and in your hands.
6. clean the top of the roof, where the seal was, there won't be much there, I used a rag and isopropyl alcohol.
6a. Clean the mating surface on the sunroof module.
7. lay a bead of sealant on the sheet metal opening (all the way around) on the top of the vehicle. (Your choice as along as its waterproof). You don't need a lot, but I used a lot (because I wanted to ensure a water tight seal). Just means more cleanup.
8. Get some help, and have a person help You put the Sunroof Module back in the same way it came out, being careful not to smear your caulk bead.
9. Clean out the Sunroof Pan, inspect it for sealant degradation, and add some sealant at the joints for insurance.
10. Using the 14 screws, re-attach the sunroof drain pan.
11. Go back up top and clean away the sealant that squished out around the Sunroof.
12. Put the Motor back on & reconnect the wires.
13. Test the Sun-roof.


Note 1. Do This, and You likely will not need to worry about your water drains again, nor will water be dumping directly onto the motor causing it to corrode.
Note 2. When You have the Sunroof module out, You might have the urge to remove the track from the glass. DON'T Unless there is some apparent reason to do this. It will only add the complication of screwing with old fasteners and the fastener glass seals.

 

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Thank you for this great write-up and level of detail. I am currently at a stage where I have had water pooling on the sunroof pan and I feel (still have to inspect in more detail) if the tube on the right side (US vehicle) is clogged.
Since I do not EVER open the sunroofs, where is all this water coming in from??, every time it rains i get at least a couple of fluid oz of water to pool there. Isnt' the sunroof seals meant to create a good seal preventing ANY drop of outside water to come in? Should i replace the rubber seals? Any chance this water comes form the fact that the original sealant that sits between the ceiling of the Disco and the sunroof may be gone allowing this much water in?

Any guidance will be appreciated, since my headliner is out now I also realized that we may have a similar leak in the back sunroof as well!

 

There are two seals that seal the sunroof, one seals the the frame to the roof. The explanation above is how to replace that seal. The other is the glass to the frame. That seal frequently shrinks and comes loose from the frame. I have no confidence in the seals nor my ability to remember to close the sunroofs (I like to use them for ventilation) therefor I do not focus on making sure the seals are watertight but rather I have figured out how to make the pans watertight and drain properly so they do not leak in to the headliner. see my other post recently on this.