VVF

Just a thought - don't forget you have a 12 year old car. Maybe the pump was weak from the age already.

BTW, while we are on the topic of fluids: what would happen to the engine if someone poured mineral oil in there instead of say Mobil1 0w40?
My friend succumbed to that as part of "diagnosis" by a questionable mechanic lol Told him to flush it out of there asap...

Moviela

I don't agree that the 12 year old pump may be "weak." As long as the correct fluid is used and the system is hospital clean inside, the only wear to the pump should be bearing surfaces and seals. Holding the wheel in lock for extended periods will damage the pump, but not make it weak. It is a pretty powerful pump, some 110 BAR. A good shop can measure the pump pressure on the car and point the direction to restore the man's steering.

Mineral oil, like Marvel Mystery Oil, is usually a mixture of chlorinated solvents and pale mineral oil. They are really not suitable for use in a Benz. The mineral oil is OK for removing lead oxide, but who uses leaded gas anymore? If you have a piston aircraft, it is useful in those engines because aviation still uses low lead avgas. The mineral oil mixtures also form HCL which lowers the TBN of the oil, thus not indicated for Benz engines or any car that has an extended drain interval.

I don't think he has spoiled his engine with temporary use, but if one had used Mobil 1 0W-40 all along, he would likely have none of the maladies' suffered with conventional lubrication.

I would suggest using Liqui Moly Engine Flush (about $10 in USA) to remove it as soon as he can. The Engine flush is added to a fully warmed engine, then allowed to run at idle (only) for 10 minutes. Then evacuate the oil following the normal oil change process. I have used it on Porsche engines that I tore down. They were cleaner than other products I tried that were mostly kerosene. The "Baby-Batter" that forms on the valve train was mostly gone.

VVF

I meant "weak" more like "in a pre-failing condition" We don't know the history of car's maintenance anyway...

Thanks for the useful info re: the oil and liqui moly flush

Steff95

Okay thanks guys. I'll see if I can get my hand on some of that oil. How much oil do I need/how much oil goes into the pump/steering rack?

Btw, who's the manufactor for mercedes PS pumps?

Found a cheap new ZF pump here: http://www.ebay.com/itm/POWER-STEERING-PUMP-MERCEDES-BENZ-C-CLASS-W203-S203-CL203-C-180-C-200-/370892899663?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item565af0854f&vxp=mtr
Don't know if it's a fake/bad copy though.. Guess it's an aftermarket one. It was very cheap compared to the prices here in Norway atleast. But maybe it's not smart to put it on my car..

turbonos7

I can't pronounce it but it is ZF...lol

Steff95

Alright, I'm a bit unsure about the quality of this product though. What do you guys think? Guess I'll get an original benz pump if not, just to be sure.

turbonos7

Update? Did you flush that bad stuff outta there yet????

Steff95

It's not that easy to find this oil here in Norway, but I figured out who has it now, and I might get it today. I am also changing the ps pump, because I'm not risking driving with the old one. If it's bad, it might send metal particles down to my steering rack, and I don't want that.. Can't do anything yet because I don't have torx pipes for that stupid reverse torx screws, and still waiting for the oil. But I think I'll might get my hands on both today.

Just hoping my rack isn't damaged already.

turbonos7

Hope so too... Good luck! And the "reverse" torx bits are E-whatever the size (I think E for European?) did you end up getting that eBay ps pump?

Moviela

Torx is an American invention designed for automated assembly to minimize cam out of conventional drivers. The sizes of the drivers are designed for maximum efficiency for the size of the thread. They are not even dimensions like hex headed fasteners, so integer numbers were assigned. The original range were called T for "Torx." When external head fasteners were developed, the head sizes were called E for external.

Steff95

That's right, I got the tools from a workshop, it was marked E **. Now I only need the oil.. Waiting for it to arrive.

It seems like the pump from eBay is exactly the same as I got from a firm selling mb parts.. And I paid a bit more than from ebay, hehe.. But at least I received it fast, and now I know it's a "safe" pump

Steff95

I'm just not quite sure on how to flush the system correctly. It seems there are many ways of doing this? Either start and stop the car a couple of times, or do the manual lock to lock with the car completely off. To flush, do I have to fill up the reservoir full, then drain all of it, and then refill again? Or can I just fill a little bit each time?

I know how to bleed the system though, manual to manual lock with car turned completely off, but what's the easiest way of flushing, and how much fluid do I have to fill each time before draining again? Is it necessary to fill up the reservoir full each time? Will I damage the pump if not?

VVF

There's a DIY: https://mbworld.org/forums/c-class-w...flush-diy.html
Or
How about this method:

Steff95

Alright, I removed the old pump now and drained it for oil... I can clearly see a lot of small metal parts in the oil... Wups.... Will I still have to just do the regular flush procedure, or is there anything extra I can do to try get most of the metal parts out? Do you think there's still any chance the rack would survive this?


I'll just have to try flush it and cross my fingers.. Is there really anything else I can do, or should I just try? Maybe the damage is done already, I guess I don't have anything to lose..

Can anyone explain to me what these small metal parts do to the rack? I mean, does really even the smallest metal part kill the rack? How? I know it would wear/tear the rack more of course, but is there anything like gaskets that gets worn out before anything else? Or is the whole rack garbage after something like that?

And what's the return and out line on the pump? Is the steel pipe the out line, and return coming from the cooling system?

VVF

https://mbworld.org/forums/c-class-w...ng-donuts.html

Steff95

Oh, look at that. Thanks!


I recieved one litre of oil a few days ago, and did a flush... I spent around 0.7L to flush away most of the metal particles.. I actually ordered 2 litres, but they were out of stock... So I think I'm getting the 2nd one tomorrow....

My problem though, is that I only flushed the steering rack, not the cooling system/return line. So I wondered if it's possible to use another kind of oil (that doesn't have the 345.0 approval) for flushing away all the bad metal particles ONLY in the cooling system, and then use like 0.2-0.3L 345.0 approved oil to flush away the "bad/wrong" oil? I will disconnect this from the steering rack and PS pump of course. Because these parts should already be clean/empty for metal particles.

(There is already around 0.3L new 345.0 oil in my steering pump/rack system, so I have some spare for flushing when I recieve the other can of oil... But I don't think I have enough to flush away all the metal particles from the cooling system, that's why I wondered if I could use another kind of oil to remove these particles from the cooling system/return line, and then flush the bad oil away after?


I hope you guys understand what I mean, and it wasn't quite as easy as I would think to find this oil... I didn't get the pentosin chf 11s, but a similar one (febi 21647 I believe). It has the mb 345.0 approval, and it has the correct colour (green/"amber green).

VVF

Try to find an inline PS filter, and have it installed when you do the "pressure flush" like in the video.
I believe it should be able to capture the majority of the particles...

Depending on how you flushed it, you may have "automagically" flushed the return line.
Basically the operation is like this: pressurized fluid from the pump enters the left/right portion of the rack, depending on how you turn the wheel. Conversely, the un-pressurized fluid from the opposite portion of the rack is forced out via the return line back into the reservoir.

See this picture. I think the cooling line is a part of the return line, but it doesn't really matter.

Steff95

Oh, okay.

What I did, was that I unplugged the steering rack hose from the cooling system under the car. Under the front bumper passenger side. From what I understand, there goes a hose/pipe down to the steering rack, followed by a hose from the steering rack over to the cooling system where the oil is being cooled down, and reused.(?).

So what I did, was to disconnect this hose, and turn the steering wheel lock to lock a lot of times, until I saw new oil coming out, and trying to remove most of the metal particles.

That's how I did it, so I guess there's still some metal particles in the cooling system part. Please let me know if you didn't understand.

VVF

I think if you make sure that you are able to disconnect the "cooling system" (I believe it's just a ribbed pipe in front of the radiator) from both ends, then you can even use compressed air to flush it.

Another thing is you flushed the system without pressure, so there could be metal particles still left in the rack. I would install an inline filter and turn the wheels many times lock-to-lock with the engine running and PS full. Then replace/discard the filter and all should be fine.

Steff95

Yea, that's the cooling system I'm talking about.

Okay, I could try that. Just hope I can find a good filter somewhere then...

Steff95

Wouldn't a filter damage the pump btw? If the oil flows too slow through the filter, the pump will overheat..

I was thinking of placing it right before the PS pump on the return hose.(After the cooling system/pipes in front by the radiator), so the metal particles won't get into the new ps pump... But I guess it's not good if the oil flows too slow through the filter, and the pump runs with less oil when having full wheel lock.(?)


Is there any difference between the filters, or can I just use a regular petrol/fuel filter for example? As long as it stops the small metal particles..?

VVF

I don't think it's that restrictive.
There are filters for PS systems, and other cars are using them.
You will only have it there for a small amount of time, to get the last bits of crap from the fluid. You could also try a magnet, but I'm not sure if the shavings are magnetic or not...

Moviela

Once the rack is flushed and clean, there is no need for an inline filter. If one was needed Benz would have installed it.

Do not fear the hose clamp on the return hose. It is a CLIC or CLIC R type. It has an advantage over the "aircraft" screw clamps. The OEM clamp is easy to remove and replace with an under $20 tool.

These clamps are better because they have a little give in them and will not cut into the hose or break the nipple from vibration.

I don't think running the pump helps flush the fluid. Gravity and turning steering wheel from lock to lock will move the fresh green stuff through the rack without any strain on the pump. Disconnect the return hose at the pump and blow compressed air through the hose. The use of solvents in the hoses, pump, or rack might damage the components, and won't really remove any more of the spent fluid than new fluid.

You can buy the CLIC tool on Ebay.

VVF

Hmm, I would think he took care of that clamp since he flushed the rack already lol

Steff95

Yeah, the only reason why I would install the filter is to remove the last bits of metal particles, then remove the filter after. So you mean it's not necessary? Is it enough to just blow compressed air through the cooling/return part, and it's good? (since I already "flushed" the rack? I don't believe it's 100% clean though, but it's a lot better than how it was).

And the clamp on my car was a normal screw clamp which I untightened with a screwdriver.

What do you mean by using solvents? Never heard that word before.