warnerca

Ive had several components replaced on my vario roof hydraulic system and am thinking about just replacing everything with a kit from tophydrolics. looks like i can get everything for about $1500 which is about what im paying per part to be replaced by my mechanic i am/was using... Does anyone have any experience with these referb parts and recommend using them? thanks

chad500sl

I sent every cylinder to top hydraulics and got replacements for my car. I didn't update the pump, just all cylinders. Took some work, but the roof now works perfectly with no leaks. I had one minor issue with the roll bar cylinder when I got the replacement, which top hydraulics quickly fixed. Customer service was excellent and I'd highly recommend them.

latemodel21

I had tophydraulics rebuild my pump some years back. TOTAL PROS ! I would not hesitate to do business with them again.

As to whether or not it makes sense to replace everything at one time ... I suppose that has to do with how much that piece of mind (of knowing everything is good as new) is worth to you. If you have had more then a few actual failures in the vario roof system, then perhaps the rest of the hydraulic parts are on borrowed time. ...

MikeJ65

The one that causes the most problems and can do the most damage is the front latch and that would be the first one to proactively replace, especially if you have the fancy headliner. The trunk lift and frame latches are also fairly high failure rates and are easy to replace. Doing those four would be in the $500 range and take care of probably 75% of the common problems. The pump, main roof, and load assist cylinders are all pretty reliable.

Also, the majority of roof issues are not pump and cylinder related. You can have all new hydraulics and still have roof issues. I'm not saying not to do it, but I don't think that it is necessary or something that will greatly decrease roof problems.

That said, everything that I have heard about Top Hydraulics has been positive and I think that their prices are reasonable for the work required to rebuild cylinders that were not designed to be rebuilt.

warnerca

Thanks and can you expand on the majority of roof issues are not pump and cylinder related? I was told they were all replaced when i purchased the car a couple weeks ago and just assumed they were lying to me and that is what is causing my roof issues. What else should l look at?
thanks

latemodel21

Good point on the front latch (that is a part I should replace on my 2003, proactively)

I agree about the "the non-pump/cylinder related parts" being an issue as well. One that comes to mind is the https://www.mbdirectparts.com/oem-pa...ate-2307500111 . This kit includes 2 updated design parts (and the mounting screws) and is less than $50. If left in place, the original part(s) eventually fail when it is least convenient.

Cheers,
Chris

MikeJ65

Yes, two of the more common problems are the flap rack and pinion drives as Chris pointed out and PSE pump problems. The PSE only has one function related to the roof - reading the trunk divider switch, but if it goes bad and blows a fuse the trunk divider will show as open and the roof won't open.

You can also break off the alignment pin on the right leading edge of the roof which actuates the roof closed switch. It can stick in the switch giving you a roof closed signal when it is open, or it can fall off and you will not get a roof closed signal and the roof will not latch.

Another common problem is a malfunction with any window. The roof module asks the door modules to lower the front windows to the short stroke position and report back when they are in position. The RVC itself lowers the rear windows and checks positions. All four window positions must be verified for the roof to work. The trunk (tubular frame) open cylinder has a limit switch on a long plastic rod that is prone to failure.

CAN B communication is essential for roof operation. The RVC must communicate with the Lower Control Panel (roof switch), Upper Control Panel (roof closed switch), both door modules (window positions), PSE (trunk divider), Rear SAM (trunk lock) and it also gets a vehicle speed signal. I'm not sure where this comes from, but it probably originates from the wheel speed sensors read by the SBC on CAN C and gateways through the EIS. So, that would be around 9 modules that all need to be working and communicating for the roof to work.

There are another dozen or so prox switches that must all work, have good wiring to the RVC, and have good grounds. In addition, the roll bar must be functional or at least verified as down. There are a total of 7 electric motors that need to be working - the four window motors, PSE motor (at least not locked and blowing fuses), hydraulic pump motor, and the flaps motor.

What is your roof doing? Does it start to open, are you getting any messages on the dash?

warnerca

Wow, thanks, thats a lot of stuff. Mine will start to open, and the trunk gets a bout 4 inches up, then stops. And will not go back down. The mechanic im using says first replaced one the hydraulic cylinders, and now says roll bar cylinder is leaking and needs to be replaced. However, i did get confirmation that all seals were replaced before i purchased the car so im starting to think my mechanic doesnt know what hes doing or the other mechanic didnt do the work he said he did. Im taking it to the dealer this week and going to attempt to get the real story. thx

latemodel21

WOW ... great detailed list! It is often shocking how much there is to know about these cars.

Only thing that I can think to add (that is somewhat common failure item) is the gas strut for the tubular frame (buried in the rear trunk wall). When this starts to go, the trunk may move in a jerky fashion and can clunk when it reaches the fully open position during the top up/down process.

Cheers,
Chris

MikeJ65

warnerca,

The trunk just coming up slightly is often low fluid or another reason for lack of hydraulic pressure. It is possible that you had a leaking cylinder that need to be replaced and then a roll bar cylinder with an internal leak, but I get a bit worried when it starts sounding like someone is just throwing parts at it.

Frederick NL

“Im taking it to the dealer this week and going to attempt to get the real story. thx”

The dealer will strip you financially and they’ll probably refuse to give you guaranteed functionality. Get their quote, if you must, easen your heartbeat, then dive into the alternatives at hand.

warnerca

So, interesting twist on this. I called my local dealership and they actually told me to take it to a private shop that they use for odd roof issues like im describing here. Very cool that they actually did that. Would have been very easy to have me come in and overcharge me for what the private mechanic is going to hopefully fix. I did call him and made an appt and before i even started telling him what the issue was, he basically described it to me so im pretty he knows his stuff. Fingers crossed. Getting hopefully.

JamesMitchell

Great info in this thread, especially by MikeJ65. Thanks you for sharing this great info. This should be a sticky. Thanks again!

warnerca

Just to close the loop on my original post, I did find a competent mechanic and he fixed the roof issues for less than $1k. I got lucky because apparently these SL 'whisperers' are not easy to find. As i said in a previous post, this is who the Mercedes dealer told me to call.
So my lesson learned is since im not a mechanic, i probably should have sought out a competent one prior to buying the car. It would have saved me a ton of money and stress.

brucewane

Glad you got it sorted out. Since true SL experts are hard to find, could you post the contact information for the one that got you fixed up?

warnerca

Sure, but im in NC so probably a little far from you. Not sure why that doesnt show up in my profile. MB of High Point, 3368836979
He also gave me a run down on other things that would break and he said the ABC issues were overblown. Said it was usually just an 'actuator', not exactly sure thats the right word, but regardless he said its usually a couple hundered dollar fix. He also said the breaks are electronically controlled, and they can have have issues. Again, said it wasnt a ton of money to fix, just a nusense when it happens.

MikeJ65

He was probably talking about the ABC accumulators, which have a high failure rate and will cause brief red dash warnings when you hit a bump or dip. Most of the parts for ABC repairs are relatively cheap, but labor can get expensive on a couple of the hoses.

warnerca

Ah yes, sorry, it was accumulators. And that was basically how he discribed it, dash warning, rougher than usual ride.