w126 Sun Roof Being Pulled Open by Rocketbox - PeachParts Mercedes-Benz Forum

british_atlantic · #1 08-06-2020, 11:07 PM

I've got a bit of a strange question.

I bought my w126 a roof rack for an upcoming adventure and when testing have discovered an issue. In excess of 70mph the Rocketbox must create some pretty serious drafts as my sunroof starts to pull open. Not ideal. Normally I wouldn't be terribly concerned however I have had some experience with this and am not willing to repeat it. Pardon my digression, but I know what you're gonna say: "buy wind fairing, you idiot" HOWEVER I know this not to help. I was running a rack with fairing on my '97 x300 and at about 120mph the plastic bits in the sunroof gave out and it was stuck open. Naturally this was in winter, far from home (much swearing and coldness ensued).

I found this super nifty article about tape. For sure worth a quick read, I'll link it at the end of this. I'm thinking that since this setup is not permanent, taping around the sunroof seal might be my best bet. Just curious to see if anyone has any thoughts on this. No, I'm not crazy about putting any kind of tape on my paint but the alternatives are blowing out my sunroof sometime along my 5,600 mile journey and putting up with wind noise, or having a little residue that I have to clean off.

lmk what you all think, and here's the link to the tape article: https://mechanicalmalarkey.com/2018/06/14/what-does-tape-do-to-car-paint/

hercules · #2 08-07-2020, 07:27 PM

The sun-roof has a adjustable clutch for the cable,if too loose can allow sun -roof to slide
back under high speeds.

Diseasel300 · #3 08-08-2020, 03:31 PM

Considering that the highest posted speed limit in the US is 85mph, you might want to keep a closer eye on your speedo. Not sure where you're doing 120+, but that's a hell of a fine if you get nailed by a hi-po.

I used 1" wide electrical tape to temporarily seal the leaky sunroof on my black E34 wagon. The tape was on there for maybe 2 months and peeled off well enough. The residual glue came off with goo-gone. After the next wash/wax, you'd never have known it was there. No permanent damage to the paint that I could tell.

t walgamuth · #4 08-09-2020, 09:37 AM

Quote:

Originally Posted by Diseasel300

Considering that the highest posted speed limit in the US is 85mph, you might want to keep a closer eye on your speedo. Not sure where you're doing 120+, but that's a hell of a fine if you get nailed by a hi-po.

I used 1" wide electrical tape to temporarily seal the leaky sunroof on my black E34 wagon. The tape was on there for maybe 2 months and peeled off well enough. The residual glue came off with goo-gone. After the next wash/wax, you'd never have known it was there. No permanent damage to the paint that I could tell.

Yes.

british_atlantic · #5 09-16-2020, 03:16 PM

Not that this is a pressing thread by any means, however I have results to report.
Gaff tape does indeed seal the sunroof enough to prevent unwanted ingress of air pulling the sunroof open. The key is not to overlap.

(the rack hauled a bike, kayak, and a rocketbox from Ohio to Montana, down to Texas and back, one round of Gaff tape doing the trick for the whole trip. Photo in Yellowstone)