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Discussion Starter #1
Why do these ABC cars have an excessive amount of rubber hydralic hoses engineered into them? There should only be one flexible high pressure hose between pump and the car the rest of the system could be all hardline, there isn't enough flex in these cars to warrant so many rubber sections. It like an engineered in weak point. I own two s55's and although I haven't had any hose failures yet I know they're coming and I am considering fabricating hardline replacements for the rubber sections or possibly the whole line. Not too difficult we did race cars entirely with hard line. Look at any heavy equipment or industrial hydralic systems there are only rubber hose between flexible sections of equipment you hardly see any hardline failures. Something else that bugs me is Mercedes has a sensor for every damn part of these cars except a ABC fluid level sensor. How hard would it be to incorporate a oil lever sensor like what is in oil pan so action could be taken in event of fluid loss so pump doesn't die. I'm working on that idea also I'll let you know how that works out. What are your thoughts?
 

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Hose failures aren’t that common to warrant the expense of hardline fabrication , as most people don’t have easy /cheap access to hardline fab like you do .

As soon as a hose bursts or fluid gets low you will start getting abc warning messages . The warning comes From the drop in pressure not from a level sensor
 

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There are about 25 flexible ABC hoses, and yes, they're all weak points. The tragedy is that they're not serviceable, like flexible brake hoses.

Part of the reason is to take stress out of the lines, and part of the reason is for noise and vibration reduction. ABC would be noisier without them. That's hydraulics for you.

I agree about the reservoir level sensor, considering how much more important that is than say, the washer fluid level.

Nick
 

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In every other application of hydraulics, hoses are designed to be replaced as a matter of routine. It's only MB that doesn't get that. Compression joints have been used in hydraulics for a long time, but I don't think anyone else had used them on ABC to replace non-serviceable hoses before.

I won't take credit for anyone else's work, so if someone else beat me to it, then great, but I searched & found nothing, and it is an original idea.
I THINK I'm also the first person to use an engine radiator as a charge cooler heat exchanger (though I wasn't the first to have that idea).
I believe I'm also the first person to use an electric engine cooling pump for charge cooling.
The first to use a customised programmable thermostatic pump controller.
Oh, and a swirl pot on the V12TT engine.
And 390mm front brakes on an S600.
And a fix to the strut top bush problem that actually works.
And the first to use rear wheels at the front - now that's something that EVERYONE should do.

That will be the last time I big myself up. It doesn't come naturally, and I'm going to sell my Mercedes and buy an Audi now.

Nick
 

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Nick,

Chill, I was only joking with you, I do hope you realise that, there was absolutely no offence intended :wink

You'll regret having an Audi over a Merc LOL, all the VAG stuff these days is just a ticking time bomb :eek

Cheers,
 

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Yeah, but Mercedes rust!

People write about terrible experiences they have with ALL cars, and if you believed it all you'd never buy anything but a Toyota.

I was about to say that's not me, but I do actually own a Toyota, just not a very typical Toyota. It did have a ticking time bomb that went off.

Anyhow, I've owned 25 cars, and they all have things wrong with them. Recently though, I got a 2011 Passatt TDI for commuting, and it's been quite a revelation. It feels like it's been really well engineered, developed and built. I'm impressed and have a lot of confidence in it, and on the basis of that experience, I've decided to get an Audi for my weekend car. I'm going to miss what ABC can do though. The Audi has DRC, and it's just not real McCoy, regardless of what the marketing says.

Nick
 

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Discussion Starter #10
yea you will get a error message after the pressure drops then your brain has to react and by then your tandem abc pump is toast so a level sensor in the reservoir would give you a few extra seconds to act in event of rapid fluid loss like when hose blows traveling at highway speeds. so if there are 10 hose assemblies on abc cars that have potential to rupture with age, they all pretty much see the same pressure and age at same rate and wipe out pump every time so if you plan on keeping these abc cars maintained and working as they were designed as i plan too, then upgraded hoses (not just replaced) would be worth researching the possibilities and adding a sensor to the reservoir would be fairly easy at least for a die hard mercedes owner like myself. did i mention i love my s55's
 

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Discussion Starter #11
one more thing, these cars as well engineered as they are they are not perfect and mercedes as well as all manufactures of cars have to balance cost and quality of every component and warranty. look at aircraft hydraulic systems, they are reliable for a reason, so people don't fall out of the sky. the abc system could be modified/made to be just as reliable. well i cant do anything about leaking struts but then again neither can arnott.
 

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yea you will get a error message after the pressure drops then your brain has to react and by then your tandem abc pump is toast so a level sensor in the reservoir would give you a few extra seconds to act in event of rapid fluid loss like when hose blows traveling at highway speeds. so if there are 10 hose assemblies on abc cars that have potential to rupture with age, they all pretty much see the same pressure and age at same rate and wipe out pump every time
That’s simply not correct. The system cannot dump all its fluid instantly it takes several Minutes. I have five cl500/cl600s and a s600. On one cl500 my abc hose burst and I was 15 miles from home . I went to auto parts store about a mile away and bought 4 liters of pentosin. Filled it up with 2 liters and started driving home . Halfway home I filled it up again . Was still dripping as I got home . so it never ran empty . Pump was still fine and hose was replaced .

The pump does not die instantly at the first red abc warning . Even with a massive leak you have a few minutes and if you keep some spare bottles of fluid in the trunk you can almost always make it home or to a nearby mechanic
 

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Discussion Starter #13
That's good to know, I haven't had one rupture yet , well I did blow the high pressure power steering line backing into my driveway and it almost emptied its reservoir in the 5 seconds it took me to shut it off. I know it's a smaller reservoir but had it blown driving down the highway I probably would of lost entire car due to fire. It blew and covered catalytic converter with pentosin and did catch fire , it was small and since I was home and reacted quickly it didn't do any additional damage. Most fires start small and get bigger quickly if not quenched. I was real lucky. I'm just brainstorming on this ABC system, most people on here see it as a problem on these cars cause they're too cheap to maintain these fine automobiles, it's one of the things I like most about this car next to 500 hp. The ride is amazing, it's my daily driver. Actually it's my only car except my other s55 that wife drives.I see it every day at work ,nobody will fix anything on there cars anymore, they just run them into the ground and throw it away and mommy and daddy will buy them a new one. I would like to upgrade the few weaknesses this car has before the time comes. Fabricating new lines with military spec hose would not be any more expensive than OEM replacement ones especially for a diy'er
 

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That's good to know, I haven't had one rupture yet , well I did blow the high pressure power steering line backing into my driveway and it almost emptied its reservoir in the 5 seconds it took me to shut it off. I know it's a smaller reservoir but had it blown driving down the highway I probably would of lost entire car due to fire. It blew and covered catalytic converter with pentosin and did catch fire , it was small and since I was home and reacted quickly it didn't do any additional damage. Most fires start small and get bigger quickly if not quenched. I was real lucky. I'm just brainstorming on this ABC system, most people on here see it as a problem on these cars cause they're too cheap to maintain these fine automobiles, it's one of the things I like most about this car next to 500 hp. The ride is amazing, it's my daily driver. Actually it's my only car except my other s55 that wife drives.I see it every day at work ,nobody will fix anything on there cars anymore, they just run them into the ground and throw it away and mommy and daddy will buy them a new one. I would like to upgrade the few weaknesses this car has before the time comes. Fabricating new lines with military spec hose would not be any more expensive than OEM replacement ones especially for a diy'er
Hi,

I'm glad you said it and not me :big laugh:

I completely agree with you :wink

There are a few of us enthusiasts here who actually do realise the importance of not cheaping out on these wonderful masterpieces, some of which are up there in the Super Car bracket and available to us for a fraction of their original cost.

With correct workmanship and decent quality parts they will be going strong for many many years to come.

Cheers
 

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Discussion Starter #15
It seems to me that for the system to give you a warning message it has to drop to a low pressure which means it has already ran out of fluid in the reservoir and is sucking air and has run dry. How is that not bad for the pump? Everything I've read says that to not let pump run dry ever, period. So I guess it's more important to have a sensor in your washer fluid tank, we can't be running out of that juice can we.
 

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It seems to me that for the system to give you a warning message it has to drop to a low pressure which means it has already ran out of fluid in the reservoir and is sucking air and has run dry. How is that not bad for the pump? Everything I've read says that to not let pump run dry ever, period. So I guess it's more important to have a sensor in your washer fluid tank, we can't be running out of that juice can we.
No , the warning comes on at the very first loss of pressure , even a full system will warn during temporary losses of pressure (like when going over a bump with bad accumulators ) so you get immediate warning

That also means as soon as a leak /rupture forms that doesn’t allow the system to retain pressure the warning will pop up . It doesn’t only come on after it’s empty and dry- it comes on at the very first moment pressure is not held .

Again I’ve experienced this first hand . Plus I filled my car with an active leak to the top in order to drive home , and the red warning was on when it was full of fluid (but unable to retain pressure due to the burst hose )
 

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Discussion Starter #17
That's reassuring but I still think it would be a good idea to incorporate some kind of fluid level sensor into the ABC reservoir, the oil pan has one as well as a dipstick. Peace of mind at the least.
 

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That’s simply not correct. The system cannot dump all its fluid instantly it takes several Minutes. I have five cl500/cl600s and a s600. On one cl500 my abc hose burst and I was 15 miles from home . I went to auto parts store about a mile away and bought 4 liters of pentosin. Filled it up with 2 liters and started driving home . Halfway home I filled it up again . Was still dripping as I got home . so it never ran empty . Pump was still fine and hose was replaced .

The pump does not die instantly at the first red abc warning . Even with a massive leak you have a few minutes and if you keep some spare bottles of fluid in the trunk you can almost always make it home or to a nearby mechanic
Had it been merely a hose that started leaking on me, I might well have kept ABC and just redone all the hoses. But that's not what blew on my car. On mine, it was the rear accumulator, and it went suddenly. Got stranded then and there. Put fluid in the ABC reservoir, it flowed right back out the broken accumulator just as fast. I'd had enough.

I wish they'd had an AIRmatic version of the S600 TT....
 

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Discussion Starter #19
So what happened? The accumulator itself ruptured? Like grenades? Is that a common occurrence or were you the lucky one. Was it OEM or aftermarket. I'm getting ready to replace mine ,they are currently good but I want to catch them before they fail. The corteco brand from fcp euro are my solution. I wonder what's causing these hose failures, both my 55's have all original hoses one has 130k and other is 170k miles.
 

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An exploding accumulator is very rare . Most fail internally with the rubber air diaphragm failing inside the steel sphere and just fill up with fluid.

The air filled rubber diaphragm in the accumulators are what absorb the pressure shock in the system , so if yours are bad then the “hose rubber “ becomes the next flexible part to absorb system shock -and hoses start failing more frequently .

At this age of the cars it is imperative to replace all 4 spheres as part of maintenance . And yes there are four air cells in the suspension system , the ones known as "accumulators" are the ones which can cause a bouncy ride

the one called a pulsation damper doesn't affect the ride , it's to reduce vibration and noise

the front and rear accumulators (You need two) is: A220-327-01-15

Be advised there are two other nitrogen spheres in the system as well. One is mounted to the pressure relief valve (Part #A220-327-02-15) which is found in the front right side of the vehicle.

The other is a small nitrogen chamber (Called an Air Cell) that sits near the fuel pump in the driver side mid/center of the vehicle, (Part #A220-320-04-15).
 
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