I'm the new owner of a 2005 SLK350 as of Fri 5/24/13.
Here's my situation. Please be gentle on me. I did use the search feature and came up empty on this.
I test drove the car and it drove perfect. Everything seemed to check out ok. I put the top down and up and it worked perfect. I bought the car and drove home with the top down. When I got home I put the top up and washed the car. Then I went and took a shower. I came out and was ready to take my new ride out. I drove down my street and when I made my first right turn oil poured all over the place from the front right of the top. So I went back home and did a search and found this site and found out it's my front hydraulic cylinder. So I pulled the headliner down and found the previous owner stuffed paper towels between the headliner and the roof. (JERK)
That being said. I searched all over for a DIY on a fix for this. They all seem pretty difficult. So here is my thought. Someone please tell me if this is possible.
Ok here is my idea. Is it possible to Bypass the front hydraulic piston ( The one that locks the latches) by removing the two hoses and capping the open ports on the pump. And then just manually locking and unlocking the latches? I searched everywhere and couldn't find any info on this.
If it's possible. Does anyone know what size bolt I would need to cap off the ports where the go into the pump?

 

I have a 170 and assuming there isn't a lot of difference in operation between the 170 and 171 tops, I think you may find it easier to fix than you think. a subscription to ALLDATA, which can come in handy down the road too, and send in the cylinder for a rebuild and all will be swell again. when everything is working that 350 is pretty nice. they are worth a few headaches.

 

Thank you Brookings. I have a rebuilt hydraulic piston on the way

 

All fixed. What a PITA getting to the pump. There were so many bolts just to get to the pump. I Think Mercedes put 100 bolts just to make people go to the dealer to fix things.