Suspected very noisy power steering pump

[MikeEC]

Hi everyone.

I got a 2005 C 200 1.8k two weeks ago and there is a whine that changes pitch with the revs that I suspect is coming from the power steering pump.

I thought I would try new fluid before replacing the whole pump and got recommended fluid that is green. The old fluid is yellow so now I am not sure I got the right stuff.
I would be grateful if someone could confirm I have the right stuff.

 

[Trickythemerc]

You probably need a new pump, the fluid will be CHF when new it will be green but goes yellow with age/use. Just changed mine, it needs about 1 litre plus to do a change with a bit of a flush.

 

[Benzowner]

Power steering pumps usually make a noise on full lock, if you are getting a noise related to engine revs, I would more than suspect a bearing rather than the steering pump

 

[MikeEC]

It's coming from the side the power steering pump and alternator are so hopefully I am right about it being the pump. The alternator looks like a pain to get at. I've just had another look and the fluid is overfilled as well. If it's still noisy after a fluid flush I will have the belt off and spin things until I find the noise.

The car had a new timing chain a few years ago.
What kind of noise does the supercharger compressor make when it's knackered?

 

[colinallcars]

It's coming from the side the power steering pump and alternator are so hopefully I am right about it being the pump. The alternator looks like a pain to get at. I've just had another look and the fluid is overfilled as well. If it's still noisy after a fluid flush I will have the belt off and spin things until I find the noise.

The car had a new timing chain a few years ago.
What kind of noise does the supercharger compressor make when it's knackered?

It makes a kind of whining noise even when it’s not knackered. Maybe there’s nothing wrong?

 

[Stratman]

My first thought was an alternator bearing...

 

[Gazwould]

As post #2 .

 

[MikeEC]

It's coming from the side the power steering pump and alternator are so hopefully I am right about it being the pump. The alternator looks like a pain to get at. I've just had another look and the fluid is overfilled as well. If it's still noisy after a fluid flush I will have the belt off and spin things until I find the noise.

It makes a kind of whining noise even when it’s not knackered. Maybe there’s nothing wrong?

Sadly the noise it makes sometimes turns heads.

The car runs well so hopefully I'll get lucky.

I'm glad it's got the right fluid in. I won't have to waste a load of fluid flushing it 100%

 

[MikeEC]

My first thought was an alternator bearing...

Is it a pig of a job to remove the alternator if it is?

 

[Tonygw]

you can easily check what's making the noise with an automotive stethoscope or if you don't have one, a long screw driver works. With the engine running put the screw driver tip onto a none moving part of the component you want to check, say the power steering pump, and your ear to the handle end of the screw driver, if you hear the noise but its very loud you have found the issue, check also all the belt pulleys etc. Noise travels in the engine bay and can send you looking in the wrong direction if your not careful. let us know how it goes.

Of course, be careful as there are a lot of moving parts you dont want to touch when checking this!

 

[MikeEC]

With fresh fluid in the steering us lighter and a noise has gone. I say a noise because there is still a racket coming out the engine, like one instrument in the orchestra has stopped playing.


I've noticed the engine oil is closer to minimum on the dipstick than I thought. (driveway slopes), do these cars dislike not being full of oil?

 

[grober]

IF you have an overun pulley on the alternator they often go noisy.

 

[MikeEC]

IF you have an overun pulley on the alternator they often go noisy.

Hi grober,. How do I tell if I have one?

I will top the engine oil up tomorrow and if that doesn't help I will have to get the serpentine belt off and spin things one at a time. I got a stephascope but I'm not sure that I am using it right. The power steering pump sounds better though.

 

[grober]

Hi grober,. How do I tell if I have one?

I will top the engine oil up tomorrow and if that doesn't help I will have to get the serpentine belt off and spin things one at a time. I got a stephascope but I'm not sure that I am using it right. The power steering pump sounds better though.

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[MikeEC]

This is not going to have a happy ending.

I've exhausted what I could do to identify the issue and the noise was noticeably worse last night when I moved the car on the drive. I took it to a German car specialist who were good enough to have a listen. The noise drew three mechanics out and they all agreed it was most likely to be the head of the engine close to catastrophic failure.

I'm taking it back to the dealership I bought it from tomorrow as they have told me they will honour the short warranty they give on all cars. I hadn't thought of this option until the German specialist garage suggested it.

I'm a bit gutted. The car is in great condition apart from the impending catastrophic engine failure.

 

[grober]

If its an M271 engine then its likely the timing gear-if you do a search on this engine on the forum you will get more info

 

[optimusprime]

Could be one of a number of things . Slack belt , bad pulley beariings , stering pump ...Take it in and get someone thats competent to lok at it ASAP if the steering packs up you will be in c--p street ... Or if you can do it,, replace the fluid, and fit a new filter re fill and bleed the system of air.Do this by turning left to right ..dont hold the wheels on full lock . I find a gravel patch on the road park on it and then i turn the wheels left to right as per manual .

 

[colinallcars]

Could be one of a number of things . Slack belt , bad pulley beariings , stering pump ...Take it in and get someone thats competent to lok at it ASAP if the steering packs up you will be in c--p street ... Or if you can do it,, replace the fluid, and fit a new filter re fill and bleed the system of air.Do this by turning left to right ..dont hold the wheels on full lock . I find a gravel patch on the road park on it and then i turn the wheels left to right as per manual .

I wouldn’t do any of that if it’s under warranty, anything you do could invalidate it.

 

[grober]

The Complete M271 Engine thread. ( Revised and Updated ) | Engine

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