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Discussion Starter #1
As title says, I replaced the rear accumulators and now have a steering gear message. The system in the reservoir is not empty, has a little bit but not enough to hit the dipstick. where is the sensor? at the bottom of the reservoir?

The steering gear does infact feel like it is low on fluid. it growls when turning. did I send an air embolism to the power steering rack? Would purging air via release valve help in this instance? or should I focus on the adjustment arm that I flip to "Fill" a few times? Have not done any of this, just replace the accumulators.
 

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Discussion Starter #3
found this

There is a power steering whine in the MB system once some air has been trapped inside the system.. the amount of air determines the level on the whine, which is air continues to leak into the system can lead to "graoning" with that large of amount of air then in the system rack failure becomes a possibility.

The MB system uses a reservoir, and in that reservoir is a small nylon screen to prevent "cavitation" - or noise from the returning fluid.

When a small amouint of air gets into the system, that nylon screen blows out - and once blown out, all things being brought back up right, will still cause a small whine.

The end run fix is to replace the reservoir and the reservoir o-ring, then bleed the system properly (engine off/nenver on, front end up, lock-to-lock about 30 times) to clear any air - then if you have done this right, and the air gone, then when the engine runs you should not hear any whine. In the bleeding procedure, then engine goes on even for a second, the air will blow out that reservoir screen again and all bets are off.

Although ML's are more prone to reservoir o-ring leakage, I have seen it happen on a few W210's (and a LOT of W140's) - all the same cure.


It can get to you, it really can, but it is possible to go back to noiseless/no-whine, but takes very patient methodical effort.
 

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2002 E55 AMG Sedan
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Did you fill it with the correct amount of fluid? How much was lost and how much did you put back in? And what did you do to bleed the air that entered when you replaced the accumulators?
 

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Discussion Starter #6
I had alot of fluid come out of the accumulators, at least a liter total (where were torn). The lines did not really give off much fluid.

I am thinking perhaps the system is just very low. When I peak into the reservoir, I can see where the sensor is and it is not covered in oil. I will fill her up and see how things feel after some bleeding .

waiting on fluid to come in mail (my system calls for febi power steering fluid not hydraulic oil per se)
 

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88 560SL - 01 C240 - 02 W210 4matic Wagon - W212 4matic wagon
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The system as far as I know should bleed itself. Mine always has. The PS and the rear suspension for the wagon share a common pump and tank. Match the fluid purchased to the number on the tank lid -- this is important. When mine was new to me about 10 years ago it was still under CPO and the dealer used the incorrect fluid when they replaced the rear struts. Ended up being a real pain ... for them. MB has so many different fluids and they call them PS in one spot and hydraulic in another There is also a small filter inside the tank ... When I did my accumulators a few years later we did not have to add much ... as the fluid could be reused. A few months ago I had a line go and the whole system leaked out .. Think it took 5 L's . Anyway .. use the correct fluid .. think I got it from Autohauz. itls especially important in a cold climate
 

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88 560SL - 01 C240 - 02 W210 4matic Wagon - W212 4matic wagon
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mr has correct .... although

Autohauz sells it for $13.64 part 001989200312 -- The filter is about $11. Get a few other items to hit free shipping. They are a great place for filters and bulbs -- they also sell the OE inserts for the wipers that you can't get in the USA though the dealers.

You don't want the 343 specification
 

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Discussion Starter #10
thank you all for tips and you are all correct.

I replaced the little filter in the reservoir, uses interesting little hook that clips to the hose.
the fluid it ended up being febi, no problems but it was about 22 dollars on ebay.
the system did "bleed" itself once the reservoir is full of fluid. it fits quite a bit extra in the reservoir
for safe measure, using MB directions for the hydraulic system, I bleed via drain valve, very easy.

I also undid the linkage on the self leveling valave , threw the lever into Fill position, was easy but who knows if it was necessary. Hardest part was undoing the linkage, had to use sockets instead of box wrenches.

http://www.w124-zone.com/downloads/M...is/32-0630.pdf
factory procedure.

 

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Discussion Starter #11
I forgot to mention, on the e320 wagon, the accumulators were so easy to do, assess was easy, pleasant if that is possible. I was concerned that it being a midwest car, that the lines would give me a hassle. did not even have to use line wrenches. the lines themselves do not bleed off too much fluid when open.
 
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