I believe the leak is at a cylinder on the left side
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1999 Mercedes-Benz SL500 Question: my convertible top hydro system is leaking where can I obtain a repair manual
Answer #1Boca-Star Services and Repairs from Boca-Star Services & Repairs, Inc., April 28, 2013, 11:41Enthusiast
Have you ever replaced any of these cylinders? Typically they leak one after the other because the pressure keeps increasing in the system.
You have 2 cylinders on the left side of the trunk, one is the latch for the left rear of the top and the other is the ram for the fabric bow.
Its highly recommended by most experts to replace them all at the same time.
We just completed 2 W129s with the same issue, they typically have 11 or 12 cylinders.
You are welcome to drive by so we may take a closer look.
Thanks for posting