You notice the water appears to be coming in at the top of the A pillar where the roof rubber should seal against it.... you look carefully and notice there's a gap between the two surfaces.
I've had the experience and the problem. My first attempt some years ago worked - well mostly. If it was a heavy downpour, the water got in eventually. I had used a cut out piece of an old inner tube and stuck it to the A pillar side of the rubber junction. It was a reasonable solution except the inner tube rubber is thin and hard.
My new Z3 project has the same gaps as described above. I considered going down the same road with inner tube rubber pieces.
I happened to stop off at a computer shop to collect some printer cartridges and whilst standing at the check-out, I noticed a stand with "mouse pads" hanging on it... da daaaa !! the perfect thickness, consistency and density. I bought one - black with some crap on the top side. A quick flick of my thumbnail and I lifted off the fancy picture and peeled it off.
Anyhow, dropped the top, marked out a "shim" for both left and right roof rubbers and contact glued them on. Shut the roof and took the hose to the roof.... Success. it created a watertight seal by allowing more compression where it needed to and sufficient spongy thickness where it was less compressed. Not only watertight, but doesn't allow any wind to push water into the cab... Bottom line, if you want to fit a "shim" between any two ends of any two rubber sections, the mouse pad rubber will compress and provide the seal you need.
Another cheap(ish) DIY solution to improve the quality of your driving experience...
, BMW Z1, BMW M3 CSL, Z4M Coupe
