940: Moonroof Leaks ?

[thelostartof]

So right here my moon roof leak on my 1991 744. It might of leaked when I first swapped it in or within the first few years of being installed. Being that I do not have a headliner on this car (race car) it can be annoing having water dripping in your face as this is the drivers side.

Any common tips or tricks to get this to stop leaking? I just washed the car today after letting it sit all summer and sure enough my seat was wet and it was still dripping on the test drive.

[ZVOLV]

Sunroof leaks are commonly from clogged drains.

Open the roof, and pour a water bottle into the gutter and see if the water drains unevenly or rises to the rim quickly.

Use low air pressure and blow out the drains. Be careful, too much pressure and they can pop off somewhere difficult to access. You can carefully blow air into the drain holes and LISTEN to the airflow and compare it side to side. Sometimes you can HEAR a restricted drain this way.

[122power]

Have the same issue. Drains not clogged. Might be where the pan is put together? The seams? Im still tracking the leak down grrrrr.

[rearwheelpeel]

My 960 glass sun roof was leaking from the gasket that seals around the glass itself. I ran a bead of silicone or rtv (can’t remember) all around where the gasket meets the glass from the outside and tried my best to get the inside edges. It took some patience to make the silicone not look awful, but I have not had any leaks since and this was done a few years ago.

[VB242]

+1 on my '89 780, but I just smeared it on there. I was wondering if the stuff they use to repair stars on a windshield would seep in there and harden up and seal the glass.

[dalek]

I have seen replacement seals for the glass sunroof

[gsellstr]

I didn't have that on mine, but mine was leaking out the back of the track, into the headlinder. The seal around the glass failed, so water was following the glass to the frame where it attaches to the sliders, then into the track, out the back (no plug in the back of the track), then into the headliner.

I do remember on the V50 there was a similar issue to what you're seeing, where water could go around the front of the track, then out of the drain area, and into the pan where it wasn't sealed, causing a leak about where you're seeing. Best bet would be to check drains line Zach mentioned, then have someone slowly pour water into the pan while you watch to see where it's leaking from.