Has anyone figured out what the sticky stuff that clogs up the sunroof drains consists of ?

I got the driver's side reassembled and working again but I might pull it apart and add a splice (3/8" copper toilet supply line - it is all low pressure plumbing, right ? ) to take the tension out of the line.

One of the initial problems looks like the tubing down from the sunroof drain shrinks lengthwise and pulls out of the rubber firewall fitting.

On the passenger side the rubber gizmo is plugged up with some sticky junk. I can't blow through it but about 40 psi will get through it. But it does not remove it. I'd go after it with a solvent if I knew it wouldn't kill the rubber piece. Currently I'm marinating it in dish soap.

Anyone had luck clearing these ?

Thanks

Greg

I'm about to replace the drain tubes on my wife's V70 as they've blocked and flooded the passenger footwell twice. The first time with 3" of water which required pulling out the carpet and pad and using a shopvac to remove the water. The pad is about 4" thick so it stayed outside drying for a couple of weeks.

Every oil change I run thick string trimmer line down each drain and follow with a mixture of water and bleach until I see water draining below the car and the sunroof catch basin empty quickly.

The second time the drains blocked the tray overflowed into the headliner and down the inside of the windshield. I just got the leading edge of the headliner glued back in place. The foam backing had disintegrated from the water.

No sunroofs (or convertibles) ever again.

Erwin

I do not know about sunroof drains, but I had a lot of trouble with the trunk drain of the '90 744TI that we had, the drains clogged up all the time.

In the case of the 740 drain, the fitting that the hose fit into was too small, causing the hose to have a crimp in it.

After you get things cleared up, I have two suggestions.

First, on a regular basis, pour some water into each drain to see if it comes out the bottom.

Secondly, I took a piece of high temperature wire (the insulation was stiffer then regular wire) and cut it to the proper length, to use as a clearing tool for the hose..

I'll try that. I tried a section of string trimmer line but it was too soft to make the first bend.