Thread: Leaky sunroof

Broken or blocked drains are the cause of nearly all sunroof "leaks". Be careful that any tape you apply doesn't damage your finish, because lots of them will.

Yeah, I'm a little worried about when it comes time to take the tape off

I've taken the roof rail cover things off and can see the drain hole and can get to it easily enough. Just need to work out how to attach the tube to the hole now.

Possible idea, and I don't have the parts for it on hand but, tap out the hole and get a threaded hose barb to insert from the underside

Originally Posted by BigWhiteDog

Yeah, I'm a little worried about when it comes time to take the tape off

Hair dryer, and/or diluted eucalyptus oil, will help. Don't use full strength oil, it can harm the clear coat. Citrus oil can work too, same warning. Hot air guns are too hot, so care would be needed. They don't use them for paint stripping for no reason..

Personally, I'd avoid tape if I could.

Definitely trying to avoid tape if I can. Just need to come up with some way to temporarily connect the drain tube to the sunroof tray.

I could drill out the hole and silicone a poly hose barb in, but also don't want to make a more permanent fix harder with the temporary one. I'm really struggling to come up with something, my brain is taking the day off today

Temporary fix done!

Drilled out the drain hole to 8mm and had some 8mm OD tubing that I pushed through and held in place with some butyl tape, hose clamped the drain tube to that as best I could. Poured a jug of water in the sunroof tray and it all ran out under the car

Permanent fix will be a 1/8" BSP to 12mm hose barb. Just need to drill out the drain hole and tap it, then, hopefully, happy days

These fail due to steel drain in aluminium body. Dissimilar metals aren’t a good idea. The drain in my previous L494 leaked after I sold it and too k out the e-diff ECU. I have read of them causing major damage when they have leaked. So check them if you have a L494 or FFRR with a sunroof.

Originally Posted by Geedublya

Dissimilar metals aren’t a good idea.

Why not? They last the length of the warranty.....

The whole sunroof drain tube is a poor solution to the problem. Even if everything is clear and clean, if more water enters the channel than can be drained out the tube it'll overflow into the car. There are multiple points of failure along the way: blocked tray openings, blocked tube, disconnected tube, blocked outlet, this corrosion problem.

It would be much better to have the channels extend all the way to the end of the car and empty out into the rear hatch area (outside the seal, obviously). Wouldn't be as modular I guess, but would never leak into the cabin