Bob M

Yesterday I noticed fluid leaking from the right A pillar, which I assume is coming from the front lock cylinder or an associated hydraulic line.
Does any one have a link or diagram or has anyone had this happen to them.
Once I top up the reservoir do I need to bleed the system. I caught the leak early so I didn't lose much fluid.
Any tips would be appreciated.
Thanks

Top Hydraulics

Bob M,

you have a leak from one or both of your front top lock cylinders 1298001672. The hydraulic lines going to the cylinders and to the distributor 1298000022 are made of steel. If the front lock cylinders A129 800 16 72 are still original in your car, then they have hung in there much longer than the average. Every hydraulic cylinder in every modern convertible will eventually fail, unless the car gets wrecked prematurely. They can be rebuilt and upgraded by Top Hydraulics, which makes them better than new, on account of the much better seal material used.

Your profile doesn't currently show where you are located. If you are in a hot climate, like TX or FL, then I would bet that your front lock cylinders have been replaced with new OEM cylinders once already. If you are in a cooler climate and the car is a garage queen, then this could be the first failure.

Here are step-by-step removal instructions for the cylinders: http://www.tophydraulicsinc.com/R129...%20Removal.pdf (these are high resolution; may take a while to download). Attached below is a location diagram for all twelve cylinders in your roadster top hydraulic system.

There are four types of seals in your cylinders, all of which decay with time, and at different speeds:

1) Rod seals. Those are the cup-shaped seals that seal the cylinder shaft from the housing, and they are typically the first ones to fail.
2) Piston seals. Failing piston seals cause internal leaks and lots of other problems. Especially in early model years, it is essential to get the piston seals replaced and upgraded.
3) Cap seals aka gland seals. Just a static seal between the top cap and the cylinder housing. No big deal.
4) Port seals. They seal the hydraulic line fitting to the cylinder. This is a big deal. Port seals do fail with time, and their replacement involves a lot of know-how and precision tools. These are not o-rings. They seal on the edge. The brass bushings that hold them in place are made to 1/100 millimeter tolerance. Our replacement port seals are made of Viton, molded to an extremely tight tolerance.





Please remove your two front lock cylinders and send them in for rebuild & upgrade, or use Top Hydraulics' optional core exchange service. With the tonneau cover open, you can examine the ten cylinders in the rear for leak. If they are accumulating any oil on top, where the chromed shaft is coming out of the cylinder housing, then they are ready to fail. If ANY of your ten rear cylinders are leaking, then you will find them ALL leaking in short order. You will save yourself a lot of trouble, frustration, and money by dealing with all of them at the same time.

The system is self bleeding.

Klaus

www.tophydraulicsinc.com

Bob M

Yes you are correct. I had a leak in both front lock cylinders. I removed the old ones and ordered rebuilds from Top Hydraulics.
Fast delivery, great help with the R+R process.
Old ones will be returned ASAP, these guys are in my favorite list.
Thanks for your help

Somalia757

Not trying to thread jack but I also have a SL500 im working on now that has this issue.
I filled the fluid to level and cannot get the Driver side lock to engage.
My question is can I get the locks to activate one more time or do the locks just need to be replaced because they are done?
I am in Virginia BTW

Top Hydraulics

Somalia757,

it sounds like this is not your own car? What model year is it?
You are saying that the car you are working on "has this issue". Does that mean there is a heavy leak from one or both top lock cylinders A129 800 16 72? If so, then that would explain why one of them isn't locking all the way. The leak is so massive that the cylinder cannot build up enough pressure to move the driver side latch A129 800 07 74 all the way.

You can manually lock the top in the front, following the procedure in your owner's manual. It only takes a 6-mm Allen wrench stuck through the hole in front of the visor. The front lock cylinders get pressurized throughout most of the soft top cycle, so you will continue to have massive leaks and pressure drops while trying to move the rest of the top. If you are working on a model year '95+, then you will need some special instructions for manually locking the rear.

Unless someone has mechanically abused the front locks A1298000774 and A1298000874, they should be just fine. All you need is getting the cylinders 1298001672 rebuilt, which are mounted to the locks. Send them to Top Hydraulics with or without the locks attached, or get replacements shipped from Top Hydraulics right away in core exchange.

Here are the step-by-step removal instructions for the top latches and cylinders: http://www.tophydraulicsinc.com/R129...%20Removal.pdf

If you or your customer are trying to just sell the car with the roof inoperable, consider having all cylinders rebuilt instead and adding a lot of value to the car via a working soft top.

Klaus

www.tophydraulicsinc.com

Somalia757

You are absolutely correct, its a customer car. 1990 SL500 I did fill the unit to the max fill level, and the drivers side is leaking only and I got that side to lock this AM but now the passenger side wont lock in front or the rear. Basically the4 customer justs wants the top to lock securely so he can drive the car during the fall and wants to worry about rebuilding the locks later.

I'm covering the desk while my boss and the service writer are at lunch then I'll bring it back in and follow your directions to lock it.

Top Hydraulics

Are you saying that the front lock on the passenger side is not locking now? Have you tried to lock it manually, and have you noticed that the driver and passenger side locks turn in opposite directions?

Most model year 95s do not have the easily accessible rear locks, but some early '95's still have them. Check in the trunk, forward carpeted panel, next to the trunk hinges. If your rear locks are easily accessible, then there will be an access hole for them next to the trunk lid hinges. In that case, you can lock the rear locks by pushing down the levers with an open, thin 10-mm wrench. Otherwise, you will have to follow the instructions on page 2 of http://www.tophydraulicsinc.com/maunuallockhardtop.pdf

Klaus

www.tophydraulicsinc.com

Somalia757

Its actually a 1990 I made a mistake my car is a 95 lol
I did get the front to lock down and located the latch in the rear but can' t get it to lock pusing down on top and using the top wrench to lock it manually. So I am stuck there, is this a different procedure for a 1990?
I would take a picture but my phone got left at home.

Top Hydraulics

Somalia757,

you are a professional, making money on this job. You need to be careful not to damage your customer's car.

I was referring to an open, thin 10-mm wrench to be used on the levers of the rear locks. The levers get pushed down to lock the rear bow of the soft top or hard top. The locking procedure is also described in the car's owner's manual. You can download a manual here: http://bayhas.com/r129manu/1990%20R1...ers-manual.pdf

I would like to clarify to other readers why you have been having a hard time latching the front and the rear: the piston seals on the front lock cylinders and the rear lock cylinders of your customer's 1990 SL are likely very swollen, making it very difficult to move the locks manually. Some of these cylinders with seized piston seals can take over 100 pounds of upward force on the piston shaft to make them move. This is easy for a functioning hydraulic system, but difficult to do by hand. You may easily end up bending the levers on the rear locks when trying to lock the soft top down manually, thus damaging the expensive latches.

If you find the levers starting to bend while you are pushing them down, then abort the mission and let the customer know that he needs to at least have the front latch cylinders p/n 1298001672 rebuilt in order to get some pressure into the system. That way, there will hopefully be enough pressure left for the system to latch the rear once. I understand that your customer wants to only lock the top so that he can drive the car in fall without spending more money, but this would be utterly foolish if he ends up damaging the expensive latches. We have all cylinders in stock for core exchange, ready to ship.

One more piece of advice: DO NOT slam down the tonneau cover (storage compartment cover) manually, or the seized pistons will make the cylinder shafts bend and get damaged.

Summary: A stitch in time saves nine. Have the hydraulic cylinders rebuilt before they cause trouble.

Klaus

www.tophydraulicsinc.com
http://www.tophydraulicsinc.com/en/18-r129-sl-90-96
http://www.tophydraulicsinc.com/en/19-r129-sl-97-02
http://www.tophydraulicsinc.com/content/7-instructions

Somalia757

@TopHyrdraulics
I ended up figuring it out after my last post. I saw the top wrench in the truck and put 2+2 together.
I did have to release the drivers side rear lock, to pull the top up enough to get the stopper from pushing down on the lock. It was pretty simple from there.
What happened with that side was the stopper was not up enough for me to fully unlock that side to press the top in and lock it down.
It wouldn't lock because of the top pressing down, if that makes sense.

I did recommend the replacement of the front and rear locks to prevent future issues.
I appreciate all your helpful information and your time.
I will contact you if the customer decides to go that route.

After working on this car makes me want to buy a SL roadster maybe a 600, with paperwork that the locks have been replaced or rebuilt.