I have an 05 R230 SL500 and a newbie to this forum. The left front was dropping after one night of use. I bought valve block rebuild kit and made matters worse. After rebuilding the front valve block and installing a new front accumulator, I went about installing the hoses, plugs and refilling the Pentosin reservoir. Well, I screwed up and switched two hoses that go to the metal block above the front valve block and exploded the car killer line. Cut the line and had a hydraulic shop rebuild the line. Installed everything again and now the car is operates very weird. Sometimes one side goes up. Sometimes everything goes up but it does is more slowly that before I started this process. The passenger side seems to be the most troublesome and it is both front and back that never seems right. Every now and then the car seems about level and I tried putting the car in reverse and the passenger side falls within the first foot of going in reverse. So… I need some advice as to what to replace or what to do next. Take out the front valve block and rebuild? Replace accumulators? Replace pressure relief valves? Light the car on fire and never touch another ABC system? I thought the vario roof and roll bar hydraulic lifts rebuilds/replacements/routing was difficult but this system in kicking my butt. Thanks in advance for your advice.

 

Remove and replace with coilovers. One of the many downfalls in this system seems to be fluid temperatures, and the lack of a cooling system for this loop. Burned fluid seems to be a big part of the failures.

Regardless of why it fails, it is a consistent maintenance item that fails without too much warning and leaves the car stranded and will probably cause damage to the car when it is loaded and unloaded from the rollback.

Unfortunately to diagnose and repair, you need the xentry Mercedes tool. Between diagnosing valve blocks and high pressure pump and valve, you are going blind without it. Realistically if you own one of these cars you are throwing darts at problems without this xentry tool.

I bought a 2003 with 107,000 and the previous owner had replaced the pump at 62,000 miles. The fluid was black and the car was on the ground. I flushed with 4 gallons of new, but the car would never settle to the right level, it was doing a constant rodeo when moving. The pump pressure low but acceptable but the pump was on its way out. With the cost of accumulators, pump, valve block rebuilds, and the lines that could go bad at any time, for me it was simplifying the complex silliness.

At 107,000 miles with average or so condition, these cars aren’t going to be worth anything anytime soon. With the complexity of repair, and nighttime electrical problems, parts are going to be hard to find and very expensive. That’s my take on Mercedes ABC systems from the beginning.

 

It was mentioned to me that the solenoid wires could be crossed as well. Maybe you put them on incorrectly?The only way to find out is to get a bi directional tool that is able to lift and lower a corner at a time. By that point the xentry tool should be purchased.

I don’t have one, but certainly need it for these cars

 

When the car is stationary, ABC is in a kind of standby mode so it isn't actively controlling to the set level (unless it gets way out of the proper position). In this standby mode, the blocking valves are closed and the control valves cycle through their range of travel. If the blocking valves are not working properly, the car will rise up when stationary and then drop back down to the set position once the care moves (and ABC goes into active control). The O-rings supplied with rebuild kits are to seal the valves in the block, but the valves themselves also need to be working. Are you sure that the springs were properly installed?

There are ways to test the function of the blocking valves with DAS, but generally speaking, if the car rises when running and stationary and sags when parked for a day or two, you have blocking valve issues. You can measure each corner when you shut the car off and then check the next morning to see how much it settled. This will give you a good idea of which blocking valve(s) are leaking.

 

Where does one obtain this xentry tool and what's the cost?

 

I would contact benzninja on here he will point you in the right direction.

 

I did that, thanks.

 

You are correct. I crossed the wires. All good now. Thanks for saving my sanity.

 

You can thank mike for that one, he suggested it for me. Glad it worked.

 

Just wanted to drop a line and say good job for sticking with it... instead of going the coil over route and destroying the integrity of the car!
Good job!!!!!

 

Yes thank God you did not destroy the integrity of the car like all the other destroyed SL350s which came with coil overs.

 

Yes who would ever drive with plebeian coil springs, heathens.

 

Yeah, I saw where some fools at some hack shop did coilovers on an R230. Totally ruined the integrity of the car. A travesty, I tell you.

I think the shop was called "AMG" or something, and they called their abomination the "SL65 Black Series". Probably "black" because they were so ashamed of their utter failure.

Hideous, isn't it?

 

And totally ruined like the sl350. I wonder how anyone could drive these abominations? That one there looks like it could veer off the road at any second.

 

WOW!!! These guys with "coils" are touchy.
I love the coils in my SLK350, SLK230 Kompresssor
Love the Air Suspension in my GL 320 CDI
Heck..... I even love the coils in my two 1st generation Camaro's
Even love the suspension in the Rolls Royce!
Not trying to offend anyone! Just love the fact that people take the time, effort and money to keep the car as it was originally engineered.
Please accept my apology.

 

If it was engineered better, I would still have the ABC on the car I put coilovers on. The car was dealer serviced it’s whole life and at 107,000 miles it was on its third pump second set of accumulators and needed both valve blocks rebuilt. Doesn’t sound like good engineering to me.

The tally for these suspension repairs was just shy of $10,000 and it needed more parts to get it right.

Changing the fluid every 4 to 5 thousand miles may be the way to save these, but I have little interest in maintaining something like that when there are other much more reliable options. It also gives me more time to fix every other thing that breaks on these cars without warning. One less thing to leave the car stranded on the side of the road.

Which brings up a great point about Mercedes engineering and the fact of the car dropping down so low you can’t even drive it off the road without possibly damaging the front fenders. That’s terrible engineering and dangerous as well as unnecessary.

 

Guys, I purchased this SL-500 2004 because the previous owner was in the dilemma of spending money in the ABC or sell it at a discounted price. So, I did buy it, then subscribed to the forum and learned all about the pitfalls of the system and several tricks of the trade. Well, I took the shortcut and cheap route for the conversion and it will end costing me around $200. I actually purchased the Bilstein struts and a set of new springs, totaling around $850. Then I purchased the top mounts, bumpers and booths for around $150. Afterwards I sold my old cores for $800. Next, I will do the by-pass to the pump and will remove all the ABC junk which will cost near zero. Afterwards I plan to install a front sway bar that I found in the junkyard for $30. I will let you know guys how all this evolves. One thing in my favor, I have a metal working work shop and can fabricate/modify parts on demand. The bar I found is a 1" diameter and used to belong to a Ford Town Car. That baby will keep the front wheels as parallel to the road as possible! The geometry is pretty much usable. I have owned BMWs, Alpha Romeo's, Mercedes, and never have visited the dealers shop! Just get the repair manual and hands on the job!

 

Good looking rig, Bruce!

 

Yes as was stated to me, ABC and or convertible top issues pretty much total the car.

 

That is not my car - I'm poor, couldn't swing $300K+, so I'm having to make do with an SL600

 

That could just as easily make you poor. 😄

 

Eh, I think top issues can be addressed within reasonable $$ if you're an advanced DIYer and you invest a few hundred $$ to obtain a Xentry system. There's a couple of different shops out there that specialize in convertible top hydraulics that can provide rebuilt cylinders for a reasonable price. And the thing is, -any- convertible with a power/hydraulic top can have the same problems, so if you want a convertible, this is not a reason to dismiss the R230.

ABC, in my opinion, is a different story.... the fact is, every single part of the ABC system, from the hydraulic lines to the pump, is a maintenance item that will fail in time. And if you wait until something fails, it can be a huge problem - a failed pump with send metal bits throughout the system, causing problems in the valves and struts. A failed accumulator/pulsation damper can send rubber bits throughout the system, causing all kinds of problems with clogs/restrictions at valve blocks, etc. A failed hose can cause the suspension to collapse to the point that not only is the car undrivable, you can't even get the car on tow truck without damaging a bumper and/or the undercarriage. To me, this is why ABC is an engineering failure - it's unforgivable to build a system in a vehicle that can fail so catastrophically. You do that kind of stuff in a race car, not a retail consumer vehicle. So anyway, if you want to keep ABC, the thing to do is replace everything before it fails, basically treat the entire system like a timing belt and replace it at set mileage. From what I've seen, for ABC I'd say 70K miles. So then, the cost of parts..... aftermarket pump ~$350, all accumulators/pulsation dampers ~$750, rebuilt struts $2000, hoses $1600 OEM/ $500 rebuilt at local hydraulic shop, valve block rebuild parts are less than $100...... plus probably $200-$300 worth of Pentosin......so on the low end you're looking at $4K in parts. And easily 3-6 weekends of labor.

Some may say "but you can just replace these things as they fail and spend a little at a time so it doesn't quite hurt so much"........ look up Legit Street Cars on YouTube. Dude has a CL65 that blew an accumulator and sent rubber bits throughout the system. He's replaced or rebuilt most of the system, picked rubber bits out of valve blocks, hoses, has disassembled nearly the entire system looking for clogs from rubber bits....... and it's still not fixed. In his last video on this car, the back end is still collapsed and wont raise. He first did a bunch of engine work (ported heads, bigger turbos) then got into the ABC issues, was posting a new video on this car every two weeks for quite some time. Now it's been three weeks since his last video.... I think the dude's about ready to set fire to it

So basically, an earlier SL500 with 70-100K miles is going to be worth $14-18K and is likely in immediate need of $4K in DIY maintenance if you want to keep ABC, much more at a good indy shop. Dealership? LOL. Or you can dispense with ABC and go to coilovers, selling your old ABC struts to one of the rebuilders for $800 to offset the cost of the coilovers. A top-of-the-line kit with swaybars from VVK or RMT will cost $3-4K, cheaper coilover-only kits will cost $1200. So you can have an SL with a 100% reliable, good quality suspension for $400-$3200, depending on your choice of kit/equipment.

For me and my car, I've decided to go with coilovers and sway bars from VVK. Why not stick with ABC? My system looked good, nice clear fluid when I bought the car and no issues with ABC. Then about 5 months ago, the car spewed a couple of quarts of fluid out of the reservoir on shutdown, nearly stranding me miles from home. Got it home and had to let it sit until recently due to no available DIY time. Finally got back into it, did some research, seems this problem is usually caused by a failed accumulator. Checked accumulators and they're good. Refilled the reservoir and took the car out, suspension lifted fine, car drove fine. And when I shut it down, it puked a few quarts out of the reservoir again. Took a good look at the situation - a few ABC hoses starting to "sweat", the car has 72K miles, and a current major ABC problem. Too late for preventive maintenance, facing a possible ABC rabbit hole of parts, labor, and frustration. And I've got an ongoing house renovation that 1)needs my attention and 2)makes it really inconvenient to have an immovable car in my garage, since I kinda need to be able to use my table saw and various other things out there. Going to coilovers lets me get the car back on the road in a weekend - I'll install the sway bars later, after the house is done in a few months. And I'll have the confidence to drive the car across the country without worry. Sure, there's all the other things that could cause a roadside breakdown, just like any other car; not a huge worry, I've got roadside assistance with my insurance. What was a huge worry was having an ABC failure out in the middle of nowhere which left the car practically un-towable.

So bottom line - In my opinion, the R230 is a beautiful car with a serious flaw that can be fixed pretty cheaply. If you want a sporty convertible that is 1000% more stylish than the Corvettes/Camaros/Mustangs that you see -everywhere-, you can buy a a top condition SL500 and then spend a little extra to make it as reliable as any other convertible. And if you go a little further and go for a V12TT car......... pure magnificence. I still literally laugh out loud nearly every time I get my car out for a drive. Sunny day, gorgeous car, top down, 510 horsepower, 620 lb/ft torque...... just f@#!ng glorious.

 

Spot on, although I would guess that most people wouldn’t be able to do these repairs on their own. Juts starting the diagnosis will take $800 out of your pocket for expense. Good idea, but poorly engineered. There’s a reason that older Mercedes have poor resale values and wait till the electrical gremlins hit, that’s another level of nonsense in its own

 

And this is why I read these forums. Thanks to all that contributed to this thread and forum.

 

Thank you sir