The first thing I had to do with my pre-loved RAV4 was fix the sunroof, which leaked. The first step was to undo someone’s previous attempt at fixing it. A previous owner, faced with water coming in, had decided the best approach was to pour silicone sealant over every inch of the sunroof area, caking the whole thing in place. This did not work! Water still came in.
This is pretty typical of what happens when you try to solve a problem without fully understanding it first. I did a stupid amount of reading of old forum posts and stuff and discovered something fascinating about the design of the sunroof on this RAV4 model. It’s not watertight. It’s actually designed to leak. I know, right?
Advanced Sunroof Design
It’s pretty clever. Instead of tight seals that’ll wear out, the inner roof contains channels that divert the water that comes in down through the frame and out of some holes underneath. Genius, but with a few common points of failure. First, if all the drain holes get blocked then the frame will fill with water. That’s easy to test though, once the sunroof is out and you can pour some water in.
If water comes out the bottom, that’s fine. It did, so at least I could relax a bit on that front. Another clue I had was that it didn’t always leak. Once I had the whole thing out, and I saw there was a big patch of rust on the frame where it did leak sometimes, I ran my finger around the drain channels and found a big old chunk of rust sitting in there. So – depending on which way around I parked the car on my driveway, one side would be higher than the other. If the side with the rust chunk was lower, that channel got more water and the blockage caused it to overflow and come into the car.
From this point, it was pretty easy work. Clean all the crap out of the gutters, sand back the rust spot to stop it getting worst, repaint and refit everything. there’s still a crack in the seal that caused this, but at least it doesn’t leak into the car right now and I can relax and deal with it properly later.
For Not-a-Car-Guy, I was pretty pleased with this first victory and moved on to bigger issues.