Top hydraulic cylinder information

The top hydraulic cylinder is leaking on my 99 cab. I have found a source to buy the seals to rebuild the cylinder. Anyone know what size the seal is?

There is or was a guy on youtube who used to refurb them. Can you post any pics of the seal(s)? Can you measure the cylinder? the car is all metric so it will either be to the nearest 1 or 0.5mm

I found a local source for the seals. I just need time for the project now. Im going to remove the cylinder and take it with me so Im sure Im getting the proper seals.

Did you finally rebuilt your Hydraulic Cylinder? What type of O ring did you use? Dimensions? I plan to repair mines. Thank you

I finally rebuilt today my top hydraulic cylinders (C2 1999) with O-rings following the Ebay vendor's very detailed IFU: https://www.ebay.com/itm/Hydraulic-Cylinder-Repair-Kit-w-Picks-99-12-Porsche-911-996-997-Convertible-Ram/273328486330?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 One cylinder was leaking (oil leak below the rear right wheel fender). The other one was working fine but it seemed logical to rebuild both at the same time as it doesn't add so much time and they are 19 year-old... It took me about 3 hours: 1 hour to depose the 2 Top Cylinders, half an hour to rebuild each cylinder and one hour to re-install them. They work fine with no leak after one day and many open and close. Compared to shipping the cylinders and having them rebuilt by someone else, it took only an additional hour but saved ~$400. I will post some pictures ASAP.

Attached PDF with pictures showing how to rebuild the top cylinder with O rings (2 Orings per cylinder: one on each side)

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Great information, did you measure the O-rings? If you could post the size there is a very good chance we could find a McMaster Part number equivalent.

[QUOTE=Chris(MA);15247589]Great information, did you measure the O-rings? If you could post the size there is a very good chance we could find a McMaster Part number equivalent.[/QUOTE The size is 18x4.5 n70

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Is there a trick to getting the snap ring off?

Removing the snap ring is a little tricky. I pushed a little bit the white ring (~1mm) in order having more room to remove the snap ring off with 2 tiny screw drivers. I used a small hammer to insert the flat screw driver tip between a snap ring end and and the cylinder. Be very careful to not scratch the piston as the steel is very tender.

Good evening everyone, I have a �06 911 4S Cabriolet and both of my hydraulic cylinders are leaking. I purchased this kit https://www.ebay.com/itm/Hydraulic-C...53.m1438.l2649 and the instructions that were included must not be for my specific car. I�m following with a detailed Porsche Service manual I downloaded and included instructions aren�t that close. Specifically all the wiring in the beginning, steps 9-16 to be exact. Not sure where to go now except the �stealership� which will be the absolute last resort. Any help would be greatly appreciated everyone. Thanks in advance!

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They are a couple good videos on Youtube showing how to remove the hydraulic top cylinders and then how to refill the oil reservoir of the pump.. I posted the pictures taken when I rebuilt my C2 996 1999 cylinders a couple months ago because I didn't find any DIY for this job. On a 5 to 10 difficulty range, I would say 5. It is a 2 to 3 hours job. Let me know if you have a precise question. I will do my best to assist you if I can.

I couldn�t find any videos on YouTube showing the removal for my specific car. Can you please advise where I can find some? I�m out of town currently ill submit all my questions when I return tomorrow thank you for offering your help

not a video, but may help... http://www.cabriolethydraulics.com/articles.php

Video :how to remove the Hydraulic cynlinders with a lot of "next steps" : You Tube How to add oil: You Tube

JB001 & Rolex11 thank you very much for yalls assistance. Few questions: - please tell me the importance of the potentiometer. I read somewhere I need to tape it back while cylinder is removed to keep the computer in sync with the position of the top -I�m thinking since my banjo bolts are located on the bottom of my pump, I�ll need to unbolt and turn over to gain access? -since my car is a newer model than what�s on the paper directions and the YouTube, will I really need to disconnect & remove rear deck actuator. - I can access and remove pump without moving it & black cone (which I can�t find)?? Again, thank you very much for your assistance I tried to upload a pic of my car�s setup. But I think it was unsuccessful...

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UPDATE: was able to remove passenger side cylinder. Got it to my bench. After MANY attempts finally got snap rings off and can not for the life of me get the white seal out of cylinder body. And was unlucky enough to slightly nic the actuator rod. (See attached pic) Yes I used an air compressor with no help at all. Looks like I may be shippong them off for rebuild... Havent removed driver side yet. Still waiting on details of potentiometer. Thanks again guys for any and all help with this job.

The compressor didn't work for me. Then I sucked some oil from a glass with the cylinder and then compressed the piston. The oil pushed out the white nylon ring. Al little messy but efficient Regarding the scratched actuator rod, you can polish it as I did... for the same reason with this kit: Amazon Amazon

Thanks JB001 for your response. I went ahead and shipped them to the guy with the YouTube video, Craig. Will leave a review when I receive them back and are installed. Have a great weekend!

I trust Craig will do a good job.

Just replaced the passenger side top hydraulic cylinder seals on my '06 997 C2S. Removing the cylinder from the car by combo of instructions from previous posts was pretty easy. Removing the retaining clips and seals/stops from the cylinder by above methods was beyond my skills and/or patience. Using JB001's Rebuild Cylinders Pics PDF as a guide, my tweaks were as follows: To ease removal of the retaining clips I drilled a small hole in the cylinder wall inline with the clip location. This allowed me to insert a pin, (nail set in my case) and press one end of the clip inward which made it easy to lift out with a small pick. Wrap the cylinder rod in tape to protect from damage, (I used Gaffers tape, no residue, thicker/stronger/more dense than duct or painters tape). Using a pick or similar, rotate the clip around in the groove so the gap is opposite the mounting rib, (this assuming you'll be holding the cylinder with a vise by the mounting rib during drilling). This prevents accidentally drilling into/through the clip. On the aluminum cylinder housing scribe a line .15" from the end, this will be the center line of the drill bit, (probably should center punch as well to prevent drill bit drift). Using a 7/64ths drill bit, preferably in a drill press, (I used a mill but with great care and having center punched your drill location a cordless hand drill with a drill stop could work) drill a hole ~.175" deep. Make sure not to drill into the cylinder rod, (duh). Rotate the clip around slightly past the newly drilled hole. Using an appropriately sized pin, (I used a nail set) press in on the clip while lifting up with a pick. Repeat for other end. Once the clips are removed check for and remove any metal bur(s) on the inner surface at the hole which could impede the removal of the white nylon(?) seal retaining ring. I used hydraulic pressure to remove the retaining rings and seals. To do this I submerged both hose ends in a small jar of hydraulic fluid and moved the rod back and forth in the housing to suck some fluid back into the cylinder Then, I clamped both ends in rubber padded clamps so that pressure created by cycling the rod would press on the seals. IMPORTANT! Once the hose ends are "sealed" do not move the rod in the cylinder housing before placing rags around the cylinder at the seals, (maybe lightly zip-tie in place) to catch the fluid which will be expelled. The pressure required to displace the seals is substantial and is very effective at atomizing said fluid and coating the entirety of one's surroundings in hydraulic fluid. You can probably guess how I know this... Once the new seals were inserted I found that half a wooden clothes pin worked well to re-seat the seal retaining rings in the cylinder housing.

How do you bleed air out of this closed loop system?

I have been going back and forth between shipping off my actuators for a rebuild or taking the DIY route. After speaking with one of the groups providing a rebuild service, as well as reading their online product info, the consistent message has been that these o-ring kits are garbage, they are destined to fail, and possibly fail spectacularly with a seized actuator from the o-ring slipping out which was not designed for this purpose. But is that true? Sure saves a ton of money and I have yet to read someone that says their own rebuild resulted in a seized actuator. At the same time, the pics from BCCarrera2 gave me pause - while extremely detailed and helpful, I could see plenty of opportunity to mess this up. Can anyone let us know how their fixed actuators have held up over time, and if they took the DIY route or sent them off? Thanks!

The DIY route is a pain in the butt. Send�em to the Craig guy in YouTube. Turnaround took less than a week and they�ve worked great since install. Wish I could sell ya the rest of Porsche hydraulic fluid I didn�t use. Didn�t take much for job. Hope that helped

I used Craig he repairs them properly.

Please allow me to explain my decision to rebuild my top hydraulic cylinders : My 996 is my daily drive for 8 years. I decided to rebuild the cylinders in order avoid having to rent a car for a week on top of the service and shipping cost. Also, I must admit that I enjoy fixing my car.. PS: The hydraulic cylinders that I rebuilt 2 years ago still work perfectly but they may fail spectacularly one day according to the vendor who do not want us to install the inexpensive O rings.

No need to bleed the system outside of sucking some oil in the cylinders before installing them.

It took a while but I am glad i found this thread. I was going to use top hydraulic but they are not doing refurbishments until the end of the year. I tri d a few other spots I found online and they are not either. I did see Craig from eBay, and I am glad I see some luck by others. 400 bucks and 1 week and it will be fixed.

For anybody else looking for options. Cabriolet hydraulics has a 996 kit they sell. I�m getting mine on Wed. The kit is around $450

I checked their site and it says no available. Are you shipping them the cylinders first?

I had to call them. They wanted me to ship my cylinders first, but I can't do that since it's my daily driver. They did a great job working with me and were able to scrounge up a couple to send me (those may have been the only ones they had). I paid a $500 refundable core charge and another $50 to expedite. I'm not sure what your time table is but I should have mine out next weekend (if all goes well). So CH should get mine back the following wed or so M

Thanks. I will call them and ask. It is not a daily driver, but I just wanted to get it all done at once.

I just did the exchange took 3hrs all told. I would have been done in 2ish but it was very hot and my helper bailed on me. I’ll post some pictures but you can save a ton of time and likely some flesh by removing the back seat side speaker. The front 13mm piston nut is right there. The "c clamp" goes on way easier if you jiggle the top a bit. also don’t leave your glasses on the top when you open it M

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I never felt the need to remove the speaker. What year is your car?

2000 C4. I didn't try the other way since when I removed the speaker the nut was right there. Took maybe 30 sec. It was also nice as I could shine a light from the bottom which made it easier to catch the potentiometer M

Here are a couple pics for those who are interested Speaker off. The piston is covered by a removable plastic piece The cover comes right out and you can see the piston shaft The nut is just off the speaker hole. 30 seconds with the wrench and your done Make sure you put the piston in the guide hole on the right and capture the potentiameter on the left. Hope this helps M

Thanks for posting those pictures.

My cores are all boxed up and will be sent back tomorrow. I’ll let you know how the refund goes M

Thanks.it was too hot in Texas over the weekend for me to try. I may give it a go this weekend. Keep us posted.

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Been about a year since my earlier post up in this thread asking for thoughts on this. I ended up sending off my actuators to Craig, per fitman's recommendation. Got it done in June of last year, and they've worked like new since. Not an easy choice - I've gotten more cheap over the years, so I wasn't excited about throwing $400 toward something I might be able to do myself. But there's enough reports of pain in the rebuild (and my suspicion that Craig would still do a much better job than I could ever do on my first go-round), that I decided to put in someone else's hands. Glad I did! Good luck to everyone else with whatever route they choose, and much thanks to all the helpful posts on this thread with tips on how to get those things out (that removing the speaker bit would have been helpful for me - that bolt is tough to get to). s

Sent mine to Craig also.He actually removes the. ‘Eye” off of the shaft and replaces the seal with a better version.There are a lot of hack fixes out there be careful.

A couple of weeks ago I barely got my top up before a deluge rained down from the sky. I just sent mine to Craig today. Will report back.

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Craig rebuilt my cylinders and got them back to me very quickly. It would have been less than a week if it wasn’t for a screw up by the USPS. I highly recommend his service. I started to try to rebuild them myself but I quickly realized it was a bit out of my comfort zone and just decided to let someone do it who has done it a ton of times. He gave me a couple of tips that helped me out quite a bit. There is a sensor arm on the driver’s side. The plastic wrapped peg that slides in the guide channel goes through this arm as well. It tells the computer what position the top is in. When I was removing my cylinders, I didn’t see the arm nor was I aware of it. It seems like it’s made of plastic and if you kinda wrestle the cylinder out you could break it I would think. Luckily mine was intact. The other tip he gave was just stick the hose ends of each cylinder down in a container of fluid and slide them back and forth a few times. You will hear all kinds of tricks about how to prime the system, but this simple method worked fine for me. I’ll share a tip about something I ran into. When you are reassembling everything, if you bolt the hose ends to the hydraulic pump before attaching the top control arms don’t fully tighten the bolts until you get the arms and clips back on. The position of the peg on the cylinder has to be just right to slide the arms back over both pegs, and leaving those bolts just a bit loose makes it much easier to move and wiggle things around. I found out the hard way. Hope this helps.

Sorry to revive an old thread but can the top be shut with the rams off? Want to send mine out to Craig but no garage to store it in in the meantime. Thanks!