Repairing Leaking Top Cylinders Inexpensively

[wayneg]

Originally Posted by Hogie

Hey Guys... my first post... this forum is fantastic, great work to all of you for sharing all your experiences.

Ive just had my left windshield cylinder go and plan on repairing both of them when I can, Im also very keen to see the photos of this repair as new cylinders are gonna cost me $240 AUD each!!!

thanks again guys...

Hi Hogie and welcome aboard.
To help yourself add your vehicle model and year to your details plus location. I take it you are in Oz.
Seehttp://www.benzworld.org/forums/r129...te-thread.html
for everything you need to know about getting the cylinders fixed. I think at the moment Dennis`s reseal is the sensible way to go. There are other options that have been discussed, Cycle pump seal has worked, Seal from headlamp wiper shaft was reported to work ( no follow up ). Power Steering leak stop fluid has worked. Until now no one has come up with a correct and available seal.

[MercNut]

I just had Dennis Ficken repair 4 hydraulic cylinders on the roof mechanism for my 500SL. I couldn't be happier....they work great and the repair cost was very small compared to buying whole new parts through a MB dealer. Make sure if you replace one leaking cylinder on one side of the car that you also replace the other at the same time ...as hydraulic pressures will soon find the weak spot once a new seal is implemented.

[fredej]

Hey there Hogie!
I too am new to this site, but I’ve put in a little time on my SL, and just last week I R&R’d the hydraulics on my soft top. I was going to repair them myself, but I could not find any seals like the ones that came out of the pump, so I abandoned the mission.

The hardest part was removing the Constant Pressure Ring holding the cylinder in. Anyhow I have dissected the top roof locking pump and have attached a picture to this post. Hope this helps you!

Also, I would be interested in obtaining the seals for these pumps, so if anyone has a good connection please let me know!

Good luck!

[RKH]

I've been checking on the other R230 Forum and they have not posted much about having Hydraulic problems. I wonder if those R230 are just too young to have leaky hydraulics or MB has finally solve the fluid/seal problem.

[Lee Wireless]

In my opinion, it's not worth repairing these yourself and believe me, I like repairing things. He has all the proper tools to tear-down the cylinders. Dennis gives a 3 year warranty, his turnaround time is super fast and the price is right.

[jkmarsh]

I had my replaced this morning at my Indy mechanic. Total cost was $450. $300 for 2 new cylinders and $150 for 2 hours labor. I watched him switch out the parts. I'm not mechanically inclined so DIY would have been a chore for me.

[morriswu]

Originally Posted by fredej

Also, I would be interested in obtaining the seals for these pumps, so if anyone has a good connection please let me know!

Hi fredej,
Below is the dimension list of the all seals of the cylinders, for your reference.
But it seems to be difficult to obtain them, since they are in special dimension, not regular ones.
good luck,

MorrisWu

Parts # Seal ID Seal OD Seal t O-ring ID O-ring OD
129 800
-2172 6 13 5 13 16
-2172 6 13 5 13 16
-2072 6 13 5 13 16
-1772 6 10 4 10 13
-1872 6 10 4 10 13
-0272 17 22 5 29 33
-1672 9 14 5 13 16

[Gwillie]

I read with great interest the search for answers to the seal issue.

Here is what I think:

1. the only seal that seems to cause the leak is called a u cup hydraulic shaft seal. It is made of polyurethane. There is a static o ring around the end cap but it usually checks ok.
2. Polyurethane is normally selected for strength and is acceptable for use with mineral oils including the ones using stop leak additives. Stop leak chemicals do not appear to affect (swell) polyurethane so I doubt if there is any value other than price for using the cheaper generic fluid.
3. The failure mode based on my inspection appears to be just plain thermal fatigue or aging depending upon your background. In other words these things are life limited and a ten year life is NOT an indication of poor design -just the limit of the best material available.
4. Seals can be custom made and avoid the machining that Dennis is doing which reduces the end cap wall thickness more than I would be comfortable with on my cylinders. (1mm on a 5mm wall-thats 20% removal) Remember these may be classics and need to function for many years.
5. The use of the recommended fluid may be more for the hydraulic pump as its seals are as yet a mystery to me. They may well be damaged by stop leak additives. I just haven't been into the pump yet but until I know for sure would recommend staying with the MB recommended fluid.
6. Somebody needs to do a teardown of a pump and identify the seal failure mode. I will suspect it is the shaft seal failing mechanically just as in the cylinders and an easy fix for a grateful owner.
7. Once the seal type and material is known the price of junkyard pumps will drop drastically just as we should be seeing for these high prices for new or used cylinders.

My relevant background is in aircraft maintenance engineering and NTSB accident investigation but I could be missing something. More facts anybody?

Best regards,

[marksmerc]

Originally Posted by ogn

Hi Guys,

I'm in the process of replacing the O-ring of five cylinders (mine and some other friends from Saudi),

The whole process will not take more than 15mins for each cylinder, I have discover a workshop in Dubai will make the O-rings in front of me, and will charge me almost nothing comparing to the job quality.
However I have rebuild my rear cylinders last year and it works perfect, plus the front one (month agoand for Ahmed Ali from Saudi) and it works as new.
So good-bye for replacing the cylinders or paying a fortune to repair it.

I will post the whole process step by step next week and will ask the workshop to make extra plastics ring for me for the future.

Regards, Omar

can i get the seals from you ?? cheers

[marksmerc]

can you supply the seals or do you have the sizes so i can get some ? thanks