940 sunroof drains / seal

[vickyg]

Hi

I've seen comments that there are 4 sunroof drains, 2 front and 2 rear. I am only aware of the the 2 at the front, are there more? I cannot feel or see any others. I want to get a new seal which at £69 is quite a price. Are they a complete circle that you fit on or just a long strip? Mine has shrunk a fair bit (or broken) so there a gap where the ends meet. Parking downhill seems to help with leaks as the water is channeled into the front drains. Last week I got a good wash having been parked uphill, when I turned around it overflowed on my head. Yes very funny.

[Laird Scooby]

Originally Posted by vickyg

Hi

I've seen comments that there are 4 sunroof drains, 2 front and 2 rear. I am only aware of the the 2 at the front, are there more? I cannot feel or see any others. I want to get a new seal which at £69 is quite a price. Are they a complete circle that you fit on or just a long strip? Mine has shrunk a fair bit (or broken) so there a gap where the ends meet. Parking downhill seems to help with leaks as the water is channeled into the front drains. Last week I got a good wash having been parked uphill, when I turned around it overflowed on my head. Yes very funny.

There are indeed 2 rear drains, i can't remember off the top of my head what route they take but the first thing i would do is invest in some silicone grease. Open the sunroof on tilt and rub it in generously to the part of the sunroof seal you can see. Let it soak in for 20-30 minutes then gently wipe off the excess.
Now open the sunroof on slide and do the same to the front end of the seal that you can now see. Again, after rubbing in generously, wait 20-30 minutes and gently wipe off the excess. Repeat this weekly for 4 weeks then monthly for 3 months then again 6 months later and yearly after that.

The seal dries out and shrinks without this little service item done yearly and most people don't know about it or can't be bothered until something goes wrong like getting soaked.

After 3-4 weeks, see if you can push the seal together again, you'll have to start opposite the gap and push towards it going both ways at the same time if you get my meaning.

In the meantime, i'll try and locate the route the rear drains take, i thought i had a photo from when i changed the headliner (not a long job, about 10 minutes to get it out and another 10 to fit the new one) but sadly not. Bottom line is you need to find the exit of the drains (i think it's into the sills or wheelarches and then out of the drains in the sills or into the big wide world from the arches but not sure exactly - might even be in the cubby holes behind the rear arches, visible if you lift the lids on them. The exit of the drains is almost always where they get blocked, alternatively you can open the sunroof on slide and poke some thick strimmer line into the holes or if you have compressed air, shoot some of that down it.

[vickyg]

I should have explained I've already cleared the front drains and had several goes at refurbing the old seal with silicone spray, this was after a good clean with a toothbrush (kids thought I'd lost the plot) - I can't see that seal coming back together if I'm honest and it does sag a bit at the rear (oo-er)

The leak is now "different" including the "shower" I had last week - never had this before! I cannot see the rear drain holes at all let alone push anything down them. Used airline easily on the fronts and they flow freely.

The whole chassis of this car seems to hold a lot of water, noticeable after any heavy rain. I found a blocked bung on one side under the rear, in my enthusiasm I pulled it out whilst still under the car and got a mucky wash....

[PhilFin]

We also have had occasional 'inside cabin showers' ! Parking downhill is a must.

Think the 2 rear drains exit just behind the rear wheels. I've used plastic coated curtain wire in the past, but it's very difficult since the drain does a sharp bend downwards as you'd expect - behind the rear c post i believe. On a ramp, look for rubber hose outlet and try inserting a line upwards? Your idea of air hose sounds better.

Ultimately, a new seal sounds the best long term solution; i smear the rubber foam with vaseline ; if all else fails someone else i know silicone-sealed their sunroof.

...If you have other findings/tips i'd be interested.

[vickyg]

Originally Posted by PhilFin

We also have had occasional 'inside cabin showers' ! Parking downhill is a must.

Think the 2 rear drains exit just behind the rear wheels. I've used plastic coated curtain wire in the past, but it's very difficult since the drain does a sharp bend downwards as you'd expect - behind the rear c post i believe. On a ramp, look for rubber hose outlet and try inserting a line upwards? Your idea of air hose sounds better.

Ultimately, a new seal sounds the best long term solution; i smear the rubber foam with vaseline ; if all else fails someone else i know silicone-sealed their sunroof.

...If you have other findings/tips i'd be interested.

Oh crikey so the water runs all the way to the back, therefore I'll never see a 'hole' as with the front too. This explains a lot!

Not thad the best day car-wise. Couldn't clear these drains, couldn't get the blower resistor out (tool failure), heated seat switch refuses to come apart and annoyingly is hard soldered so can't just take it to the bench and apply a hammer....

[Laird Scooby]

Originally Posted by vickyg

I should have explained I've already cleared the front drains and had several goes at refurbing the old seal with silicone spray, this was after a good clean with a toothbrush (kids thought I'd lost the plot) - I can't see that seal coming back together if I'm honest and it does sag a bit at the rear (oo-er)

The leak is now "different" including the "shower" I had last week - never had this before! I cannot see the rear drain holes at all let alone push anything down them. Used airline easily on the fronts and they flow freely.

The whole chassis of this car seems to hold a lot of water, noticeable after any heavy rain. I found a blocked bung on one side under the rear, in my enthusiasm I pulled it out whilst still under the car and got a mucky wash....

Silicone spray will clean the seal and a toothbrush or nail brush and silicone spray is the best way to clean the seal.

However, to revitalise the seal, it needs silicone grease.

As for the heated seat switch, they do come apart easily enough.









Some pics i took when i replaced the wire ended bulb with a 3mm red LED and resistor - hopefully you can see how the switch is dismantled from there.

[vickyg]

Will tackle switch again tomorrow when in a better mood lol. Inspecting sunroof today I found this object loose in the channels. It has a part number so appears Volvo. Anyone know what it is / where it goes?

[Laird Scooby]

Originally Posted by vickyg

Will tackle switch again tomorrow when in a better mood lol. Inspecting sunroof today I found this object loose in the channels. It has a part number so appears Volvo. Anyone know what it is / where it goes?

Looks familiar but the part number doesn't come up in any of the usual searches so could be obsolete.

[bob12]

On a 745 the rear 2 drains for a metal sunroof run down the C pillar on either side and into the rear side wheel well where they drain outside behind the rear bumper. I can't think a 940 is any different but always happy to be shown to be wrong.

Bob

[vickyg]

Originally Posted by bob12

On a 745 the rear 2 drains for a metal sunroof run down the C pillar on either side and into the rear side wheel well where they drain outside behind the rear bumper. I can't think a 940 is any different but always happy to be shown to be wrong.

Bob

Thanks Bob!

So I'm probably looking for a hole underneath somewhere, that doesn't sound accessible from the top. Always going to be tricky to clear I suspect as even with air you'll just blow any muck back up to clog again. Good job our drive is reasonably steep....!