I have been on all the forums having bought a 2005 SL350 R230 with a hardtop rattle .Love the car to bits but the rattle just rear of the headrests drove me mad. Went on all the forums they all talk about this rattle [and there are lots of them even in the USA] and a silicon oil you can buy a 3m Silicon dry oil that you spread on the seals ..But I kept thinking this is a cracking / knocking noise not a rubber grind or rubber unsticking noise ..Its got to be an adjustment or something has worn , I noticed if I pushed down on the roof joint where it meets the rear side pillars it made a rubbing noise telling me that area must be loose and inside thats where the knocking or cracking noise came from . On looking at the pivot bolts I can see cork type washers as though someone else has had a go at it .. Well I kept thinking and when looking at the hinge linkage I could see two sets of bump stops one set on adjustable bolt like you would have under the bonnet to adjust the two front sides of the bonnet . So I marked an upright mark on the rubber bump-stop and with a 10 mm spanner undid the bolt and screwed it out two turns tightened up and then drove it round the block and I thought MMmmm seems a bit quieter but not sure . Got back up with the hardtop to a central position keeping the engine running and adjusted it out two more turns. Went for another drive round our bumpy side roads and guess what all cracking noises gone my smile went from ear to ear as I seen on these forums owners spending fortunes with dealers and not getting it sorted out.Some dealers dont even want to get involved if they have not done one before . So folks give this a try it may be all your problem is . As it was mine... hope Ive solved a lot of SL owners annoying hardtop rattle .Im going to try and put some pics on here with circles around the areas Im talking about .Where you see the red cross thats the one I adjusted .The other I did not touch as it did not look like it was adjustable so just try with the one that takes a spanner marked with a red cross ....All gratuities willingly accepted lol GOOD LUCK Terry

 

Awesome ... thanks for taking the time to share.

 

Thanks

 

good info

 

@Teridor
This is great information. I have lubricated all of my roof seals, but I still have a pop or cracking noise on bumps, etc. on the right hand side above the headrest as described.

When I inspected the adjustable rubber bump stop mentioned in Teridor's original post, I noticed that it had an indention on a portion of the rubber surface where it was making contact. I backed this bump stop out about two and half turns and the noise was almost completely gone except on bigger bumps. However, about 2 weeks later, the pop/crack noise has started to return (not as bad as before, but it is coming back).

I am thinking about adjusting it out another turn or two, but I'm wondering if the rubber is maybe just compressed or weakened over time? I was thinking about replacing the adjustable bump stops, assuming I can find the part number.

Has anyone replaced these, did they notice any noise improvement?

Lee
08 SL550

 

@Teridor
Update, my pop/crack noise has returned despite adjusting the one set of bump stops as described above in Teridor's original post (THANKS Teridor). However I figured out how to adjust the OTHER set of bump stops, and now I believe my roof noise is solved! It may be obvious to everyone but me on how to adjust the other bump stop, but I thought I would share anyway.

Here is what I did:
There are two pairs of bump stops (as described on Teridor's original post). One pair (left and right) is in the hinge and is only visible when the roof is half open and it is obviously adjustable (as described in the posts above).

The other pair (left and right) is visible inside the car with the roof closed, and appears to not be adjustable (or at least it appeared that way to me). You can see the one I am talking about from Teridor's last picture here (although roof is half opened in this picture):

With the roof closed and from inside the car, I took a piece of paper and tried to slide it between this bump stop and its resting point (like using a feeler gauge), and on one side (the side where the noise occurs) the paper easily slide between the bump stop and its resting point (obviously needs adjusting). Then I looked this part up on the EPC parts catalog, and it showed what appears to be an adjustable bump stop (item 140 in the image below, part number A 20 198 805 11) and a cylinder cover (item 150 in the image below, part number A 23 079 202 30):

So I opened my roof half way with the car running (do this at your own risk, the roof will only stay open for a couple of minutes, and will eventually close - you do not want to have your fingers in there when it starts to close!!!). I started pulling on the cylinder cover, and sure enough with some persuasion, the plastic "cover" slid over the rubber part of the bump stop, and then I could see the nut underneath. It was easier to take a very small screw driver and push this cover over the rubber part, rather than pulling on it. I did NOT completely remove the cover, I only slid it down far enough to get to the nut with a thin crescent wrench (spanner) against the headliner, and the rubber part was still sticking out of the cover (I really should have taken a picture). I loosened the nut, and backed the bump stop out about 3/4 of a turn, tightened the nut, and then closed the roof again, and did the paper test again.

This time, the paper would not go through, even when pushing up slightly on the roof. I opened the roof half way again (using caution), and the pushed the cover back down to where it was originally. Closed the roof, and went for a test drive and NO MORE NOISES!!!

If you are getting noises in your roof, and you don't believe it is the headliner, you might want to check these bump stops!

Hope this helps someone else!

Lee

 

Good work, Lee!

 

This is my first comment on the forum, but I saw this had to add something. I just went through this with my 2004 SL500 (R230). While replacing the rear struts I had to take out the trunk partition. With the roof half open to reach the fastener in the back I bumped the plastic cover that LEEJ was talking about. Mine had been rattling since I bought the car back in Dec of 2018. When I tried to straighten in out it fell off. The glue on the clips and attachment points had all become detached.
That's when I recognized the rattling was not from the roof mechanism but from the hard plastic cover banging against the roof structure. I took the plastic down clean it up re-applied the clips and fasteners but back in. No rattles since.

 

Great info.

 

This is an old thread. Just to clarify: both left and right bump stops originally are covered with a black plastic 'pipe' that easily comes off when you need to adjust the bump stops. They are totally equal.