Windnoise and the Windscreen Seal
03-29-2015, 04:59 PM
#1
MBWorld Fanatic!
Thread Starter
Windnoise and the Windscreen Seal
I just did another little experiment.
I used to own an E38 BMW 750i, which was a lovely car, and a brilliant cruiser. It had proper double-glazed windows (like the W220 really ought to have) and was spookily quiet at speed. I used to keep worrying about funny noises that came and went unexpectedly, until I realised that I was only hearing the noise of other vehicles around me, as I cruised stealthily in and around them. This was only possible by attending to the windscreen sealing.
Like many cars, the 750 almost certainly had the windscreen replaced at some point in its life, and the replacement didn't fit quite as well as the factory original. My brother used to be a BMW production engineer, and he described the great lengths that car makers went to get windscreens to fit just right. My replacement didn't have a perfect fit around the windscreen seal, so I tried taping up the seals, and found that wind noise reduced considerably. Therefore I sealed the edge of the windscreenwith some sort of outdoor mastic, and the car was as quiet as a graveyard after that.
Now, my 158k mile S600 had a nasty whining sound that I fixed by replacing the ABC pulsation damper a couple of weeks ago. All the noises that were masked by the whining suspension are now audible, including some windnoise from the top of the windscreen.
So tonight I taped up the top seal of the windscreen with parcel tape no less, and went out for a fast two-way cruise. What used to be a mild but obtrusive amount of windnoise had probably halved, and instead of being localized to the top of the windscreen, all that was left was an innocuous whooshing sound coming from all over, like a jet plane. Given some dry weather and daylight, I'll seal up the edge of the windscreen and get a semi-permanent fix.
I thought this was really worthwhile, and other folks might find the same as well. I'll post some before and after pictures in a few days.
Nick
I used to own an E38 BMW 750i, which was a lovely car, and a brilliant cruiser. It had proper double-glazed windows (like the W220 really ought to have) and was spookily quiet at speed. I used to keep worrying about funny noises that came and went unexpectedly, until I realised that I was only hearing the noise of other vehicles around me, as I cruised stealthily in and around them. This was only possible by attending to the windscreen sealing.
Like many cars, the 750 almost certainly had the windscreen replaced at some point in its life, and the replacement didn't fit quite as well as the factory original. My brother used to be a BMW production engineer, and he described the great lengths that car makers went to get windscreens to fit just right. My replacement didn't have a perfect fit around the windscreen seal, so I tried taping up the seals, and found that wind noise reduced considerably. Therefore I sealed the edge of the windscreenwith some sort of outdoor mastic, and the car was as quiet as a graveyard after that.
Now, my 158k mile S600 had a nasty whining sound that I fixed by replacing the ABC pulsation damper a couple of weeks ago. All the noises that were masked by the whining suspension are now audible, including some windnoise from the top of the windscreen.
So tonight I taped up the top seal of the windscreen with parcel tape no less, and went out for a fast two-way cruise. What used to be a mild but obtrusive amount of windnoise had probably halved, and instead of being localized to the top of the windscreen, all that was left was an innocuous whooshing sound coming from all over, like a jet plane. Given some dry weather and daylight, I'll seal up the edge of the windscreen and get a semi-permanent fix.
I thought this was really worthwhile, and other folks might find the same as well. I'll post some before and after pictures in a few days.
Nick
