Floobydust

The top on my 2000 has been getting slower to open/close and the other day the rear latches wouldn't close until I blipped the throttle so that the alternator could raise the supply voltage slightly. While there are currenly no external leaks I can see, it seemed like cylinder re-builds and/or other hydraulic component work could be coming, so I did some rooting around on the net and found that others have tired Lucas Lucas Hydraulic Oil Booster & Stop Leak. This is normally sold for truck and construction equipment hydraulics, but a hydraulic system is a hydraulic system even on the Benz.

So I added some at 10% (I removed 120 cc of OEM fluid and added 120 cc of the Lucas fluid in two 60 cc boluses). After it's been in there a week and been cycled through the system several times, to my surprise, the top speed improved significantly and the rear latches now latch with authority. Not bad for $9.95 plus shipping.

I just though I'd let people know.

- FD

MB-Dude

While your experience seems at this early stage to be successful, I would recommend extreme caution in adding anything foreign to the hydraulic oil system (soft top or ADS). The hydraulic fluid used by MB in the circuit is *not* the same type of fluid used in heavy machinery; one of the traditional marketing arenas for Lucas products.

Additives that are compatible for heavy machinery hydraulic fluid, may not be compatible with the mineral oil-based fluid used in the R129. There was a thread about MB hydraulic fluid awhile back… https://mbworld.org/forums/mercedes-tech-talk/116905-egad-mb-hydraulic-fluid.html

Purely coincidently, this morning I wrote about my experiences in soft top maintenance… http://www.mercedesshop.com/shopforu...d.php?t=195459

I suspect your sluggish soft top operation may be more pivot point friction and fluid quality. However, time will tell if the additive you’ve used works long-term. I would like to know how it performs. Good luck!

bobterry99

I wouldn't hesitate to try this in a convertible top system, and I'm getting some myself. The first link I looked at from a Yahoo search is this at $7.61/quart: http://www.gimmelucas.com/osc/eshop/.../products_id/9.

Floobydust

MB-Dude -

Thanks for your concern and I agree there are risks with any additive. The two things to really worry about are chemical compatibility with the OEM hydraulic fluid and chemical compatibility with the seals and tubing in the system.

To minimize these I checked for miscibility with the Lucas fluid and the OEM fluid and they are indeed soluble in each other. Second, the Lucas fluid states that it is compatible with all "oil based" systems and since the MB system is mineral oil based (albeit high class mineral oil), this makes it highly likely the seals are likewise compatible.

Most of these "extenders" increase the viscosity of the hydraulic fluid to make it harder for the fluid to squeeze past worns seals. They also usually contain additional lubricating ingredients to allow the seals to slide past pitted bores and pistons easier. Sometimes they also contain small amounts of solvents that make the seals swell slightly and therefore seal off external leaks.

Only time will tell, but it does seem to be working well now.

- FD

MB-Dude

Floobydust - Looks like you have done some preliminary investigation. Too often we humans leap before we investigate. My concern is based solely on the MB Hydraulic Fluid, itself. Perhaps my logic is flawed, but can't find a suitable alternative source for this fluid. Therefore, it must be 'special' somehow. If it was just mineral oil, it would be available virtually everywhere. But for some reason, reasonable alternatives have not been brought forward. It is quite possible that the Lucas Hydraulic Oil Booster will do all that it claims. I hope it does! Thus, I plan on keeping an open mind and watching the results. Hey, that's what these forums are for - sharing different opinions and viewpoints. Thanks for sharing.

iamsuperchris

Ok, my car has a ton of miles on it, and the roof is probably gonna start getting slow. I'd like to know that I have a good possible alternative to repairing it if it does. Its been a month - Is the Lucas fluid still working great?

lynns

At $6.00 Gold Eagle - No Leak we have discussed this topic as well.

iamsuperchris

Ya, I actually bought a whole bottle of this at Pep Boys. I filled up the reservior with it to the MAX line, and it seems to me doing more damage than repair.

At first the leak was strictly above the passenger seat by the sunvisor hinge. I just put a towl down and didn't mind that much until I get it repaired.

After putting NO LEAK in, I have hydraulic fluid coming from both sunvisor hinges (it drips on me when I drive now... yuck), and even the two little lights above the shifter console are drenched and dripping all over my shifter.

Its too bad I couldn't have had a Positive experience like most people have... Now I have to get the cylinders rebuilt AND clean out the whole windshield assembly.

MB-Dude

Don't be too negative just yet. I've never used an additive in my hydraulic system, but when my cylinders went, they REALLY flooded the upper section above the windshield - dripping oil and all. And it seemed worse with the top down - steady drip-drip-drip.

Once you have an elastic seal start to go, there's not a whole lot that will stop an ever-growing leak. Could be pure coincidence.

For what it's worth, I have been reading up and studying about additives and I'm ready to try them myself during my next hydraulic fluid change - I was the one advising caution but believe they are OK to use. Just my 2-cents.

Cheers,
Jeff

lynns

The only person that I know that had success mentioned that after adding the NO LEAK it took about a week for it to work. So you may want to give it some time. Remember this is not the end all answer. You will need to replace the seals at some point. Not only that but remember once you replace two cylinders worth of seals that will probably improve the pressure in the system and quite possibly cause other cylinders to leak. I have heard this on several occassions. If you were to take you car to a dealership they would probably suggest that you replace all of your cylinders to the tune of about $3500.00 just for parts. I have no idea what the total price with labor would be. Approx. $10K??

cmculli

Right after I purchased my 1998 SL500, I discovered the left top latch dripping hydraulic oil (strange that it wasn't dripping when it was inspected prior to purchase). I flushed the top hydraulic system and replaced the fluid along with about 10 oz. of NO LEAK. After about a week, the dripping stopped. I know I'll probably have to send the cylinders in to Dennis for repair eventually but they have been fine for the last 5 or 6 weeks.

agentMurdoc

there is an empty space where the pump is so the fluid collects in there and will thus continue to drip. If it continues to flood your interior when opening or closing, it's not working. If it doesn't flood anymore and just drips from time to time, it's probably working and the gap just has some fluid.

You could put the top down and remove the cover piece and either soak up the fluid or just replace the pumps all together.

Floobydust

Well, it's been three years since I did the hydraulic PM with the Lucas additive. The top still goes up/down fast and smooth as silk. Absolutely no leaks from the cylinders, etc. Gotta wonder about Lucas and electrics, but Lucas seems to do hydraulics pretty well.

- FD