Convertible Top Issue

[95E320cab]

My convertible top isn't performing up to snuff:

The first function of the hydraulics is to raise the rear window. The second is to raise the rear decklid. Next, the rear window, as it normally performed, slowly lowers into the original down position, then the rest of the top recedes into the storage compartment and the rear decklid closes.

The misfunction is with the lowering of the rear window. Instead of slowly lowering into the original down position, it just abruptly falls into place. The job gets done, but it's not normal and is probably doing some damage.

I don't have a good understanding of the mechanics of the system. Can you tell me, where is the fault?

Thanks much to all. Dave

[mbdoc]

Since the system is hydraulic & has a pump & reservoir, checking the reservoir for correct level would be the first step. In the trunk on the drivers side.

[95E320cab]

Thank you. That's great. Is that around the vicinity of the power antenna assembly, behind the trunk lining?

[Kestas]

It's on the other, passenger side. It's under the hump between the fender and flat trunk floor.

[95E320cab]

Thanks Kestas. How's your car running? What's the current mileage? Your signature has indicated 70,000 for a long time. I'm up to about 110,000 mi.

[Kestas]

It's up to 73K now (I just changed my signature). It's my summer car. My total driving with all cars is 12K per year. The E320 is lucky to see more than one oil change per year. I just don't put a lot of miles on my cars.

I currently retired it from seasonal service and have two issues to deal with. On is a leaky hydraulic cylinder for the top. This cylinder is buried in the quarter panel, so the whole top will need to come out of the car for repair.

The other is an Air Mass Meter code, which isn't the fault of the AMM. I bought a replacement ECU for diagnostics. The car otherwise runs fine.

[95E320cab]

Ouch. Pulling the top sounds like a beast.

I pulled the trunk liner out of my car out lunch to expose the hydraulic reservoir. It looks like it is above the minimum mark but well below the maximum. I think I'll try siphoning and replacing the fluid, just to see if it helps. The path of least resistance (cost) first.

Thanks for the ideas, my friends.

[Kestas]

I wouldn't change out the fluid unless you think it's too dirty. The fluid is around $17 per litre, the last time I bought some. It's a special, high-quality hydraulic fluid. Considering the cost of bad seals, I wouldn't mess around with any substitute.

[95E320cab]

Kestas, thanks for the suggestion. I did change the fluid after all. The top seems to work better in all modes except for the one I was trying to repair .

I have noticed I can slow the rate of fall of the back panel of the roof by quickly activating and deactivating the switch during that mode. I don't know if any of the convertible/hydraulic "gurus" out there are clued by this observation, but it seems worth a shot. Thanks all.

[Kestas]

Working from memory, I wonder if you may have a non-problem, or at least something that's not too serious. I think mine falls also, but it doesn't slam into the boot decklid. Try pulling the header bow down just a bit before the back window falls. Your top frame may have some looseness in it and the attach points may have worked loose.

[dennis300sl]

I can rebuild your leaking hydraulic cylinders for $30 each + $10 total shipping. You can read the discussions of my work in the SL forum on this website and also on mercedesshop.com in the SL forum as well. I will warranty the seal I replace for 3 years.

Dennis Ficken
16285 S. Chester
Olathe, Ks 66062

(913) 390-0506

mercedescylinders@sbcglobal.net
mainshipmed@sbcglobal.net

[Kestas]

Dennis, thanks for availing yourself to this job. You're price is much cheaper than this one guy from Florida on eBay, that offers to refurbish cylinders for $90. Although the guy in Florida advertises using seals which are made of a better compound than original and I believe he polishes the bore. If I can dig up a link, I'll pass it on to you. He doesn't seem to be on eBay at the moment.

It'll be some time before I tackle this job. I have all winter to do it.

[dennis300sl]

I use a polyurethane seal and have the ability to polish the bore as well. In most cases, the bore shows very little wear if any. Usually the most wear is on the piston rod and I do polish that.

Dennis Ficken
16285 S. Chester
Olathe, Ks 66062

(913) 390-0506

mercedescylinders@sbcglobal.net
mainshipmed@sbcglobal.net

[95E320cab]

Dennis, do the symptoms I have described indicate a defective seal? Thanks, dave

[dennis300sl]

Are you losing fluid anywhere? Does the rear window section go up smoothly or is it jerky and slow?