I finally got the wavy headliner that’s caused by the front top cylinder leaking. But all of the videos I’ve seen show the leak at the front not on the side where the headliner is wavy. How or why does it happen there and not where the actual leak is occurring. I hope I’m explaining that right.

 

gravity form drip point down

 

The headliner is a plastic shell covered in vinyl (or Alcantara depending on options), so the hydraulic fluid doesn't soak though it. The sides of the headliner are the lowest points so the fluid pools in those areas and overflows from there on to those side weatherstrips. The side strips are replaceable separate from the headliner.


When you do the repair, be careful to cover as much of your interior as you can with plastic or old towels before you remove the headliner - there's probably still a fair amount of hydraulic fluid puddled in the headliner which will spill out when it is removed.

 

Thanks for the info. I was concerned the headliner itself would need to be replaced.

 

Nah, at worst you might have to have the headliner reupholstered. That's if the hydraulic fluid has wicked up underneath the headliner upholstery and caused it to come loose.

My car has the panoramic roof with Alcantara headliner, and the Alcantara had wicked up some fluid but it was still firmly stuck to the headliner plastic shell. A new headliner was about $3K as I recall. Tried various water-based cleaners (regular dish soap, Dawn PowerWash, Simple Green) and none did any good at all. So I crossed my fingers and soaked it down with brake cleaner, followed by rinsing with a garden hose/sprayer, repeated a few times, and it came out good as new.

 

Anyone know what the part number for it is? Or better yet, how to find these types of things on my own? For some items I can look at the back of the part for the number but this one is still attached to the car and at the dealer.

 

You can probably search on ebay for r230 headliner and see a part number in the listing. You can enter your specific year and model there for a "fits your car".

To help us help you put your year model USA version in your signature.

You can also google, copilot, etc. search the internet.

 

The part that's gone wavy in your picture is the right side roof/window seal, part # 230-790-06-98 (left side is 230-790-05-98).

As always, shop around online for the best price, it'll vary a lot even among MB dealers.

 

As far as looking up parts on your own, most MB dealer websites have an online parts catalog but it's a limited version so you may or may not find what you're looking for.

You can find pirated CD versions of Mercedes' Workshop Information System/Electronic Parts catalog (aka WIS & EPC) on eBay. WIS is the MB service manuals with step-by-step instructions for repairs.

If you're looking to do any serious DIY on this car, I'd suggest you get a full-blown Xentry system which has WIS/EPC with full diagnostic and programming capabilities. Got mine from BenzNinja, very happy with the system and his support.

 

I need to brush up on my WIS/EPC skills. I’ve got the kit from BenzNinja just suck at finding stuff. Thanks for the assist.

I looked at the price and it’s around 200 bucks. For that amount of money I’m going to try to repair it. Can’t really make it look any worse

 

I have that part and will attempt to replace it myself. Also have the new O ring for the cylinder which I plan to replace rather than whole cylinder. Not seeing any fluid on headliner, roof seal or windshield but the seal has definitely deformed as shown in your phopt

 

I also have wavy seals above the windows. I dropped the front of the headliner a while back and both the cylinder and the headliner were bone dry. I'm assuming the previous owner repaired a leak but left the wavy seals.
Thanks @brucewayne for the part numbers for the seals.

 

I haven’t seen any evidence of fluid on the windshield, headliner or door seal either. I have the new o ring but nobody wants to install it. They want to change the whole cylinder. May try it myself if I find a leak

 

The O-ring repair kits will work initially, but won't last nearly as long as the original seal. The original seal is a U shape which seals better as pressure is applied against it, but to replace it with the same type you have to remove/replace the shaft clevis which is not designed to be removed/replaced. The O-ring kits exist only because you can stretch an O-ring over the clevis without damage, where the U-seal will tear.

So if you want to repair the front cylinder and have it last as long as the original did, you can get a U-seal kit which has parts and instructions on how to remove and replace the clevis. This requires drilling/grinding to allow removal of the clevis, then using a collar with a set screw to re-secure the clevis after you install the new U-seal. Here's a U-Seal kit.

Or you can replace with a professionally rebuilt cylinder from Cabriolet Hydraulics or Top Hydraulics. I chose this because the pros replace all the seals in the cylinder, not just the rod seal. I used Cabriolet Hydraulics because they provide quick connectors for the hydraulic lines that allow you to remove/replace the cylinder without having to route the hydraulic lines all the way back to the pump.

The DIY kits, whether O-ring or U-seal, only replace the rod seal. Not the piston seal or the line seals. So you could run into the issue where the piston seal fails, allowing pressure to bleed past, and so the cylinder stops working correctly even though it doesn't leak any fluid. Or the line seals may eventually fail.

Here's a diagram of the cylinder showing all the seals.

Bottom line, a professionally rebuilt cylinder is not terribly expensive and IMO worth the cost. As I recall it was about $175 for mine, including the quick connectors and shipping both ways. That was a couple of years ago, so probably a bit higher now.