ML 270CDI intermittent whine

[fastboysparky]

If i accelerate hard whilst turning when my ml is not up to temperature i get a whining noise which then stays until engine is thoroughly warm. If driven slow from cold there is no problem. Any ideas please.

 

[blassberg]

is it definitely an engine noise or could it be from the drive train?

 

[QUOMAN]

stick a long extension on the pump ,then get someone to rev the engine. merc,like bmw use luk pumps and to put it mildly.....their crap!!

 

[tom7035]

There may be some connection here with the power steering pump, you may have air in the system.
I would try bleeding the power steering system. Jack up the front of the car and with engine off, fill the reservoir to about a half-inch from the top. turn the steering full lock to lock several times, topping up if necessary. Then have someone else start the engine while you keep an eye on the reservoir and be ready to further top up as the level may drop quickly. Finally, with the engine idling, turn the steering about a quarter turn in each direction several times. Switch off, allow to cool again and do a final top up to the max mark. This procedure should clear any air from the system.
No-cost and worth a try I think.

 

[davess]

If i accelerate hard whilst turning when my ml is not up to temperature i get a whining noise which then stays until engine is thoroughly warm. If driven slow from cold there is no problem. Any ideas please.


Wife's not in the car with you saying ur going too fast m8, that could be the reason for the whining, try taking the car out without the wife!

:razz:

Had this problem & it turned out to be gearbox problems, so hope this isn't the case for you!

 

[QUOMAN]

There may be some connection here with the power steering pump, you may have air in the system.
I would try bleeding the power steering system. Jack up the front of the car and with engine off, fill the reservoir to about a half-inch from the top. turn the steering full lock to lock several times, topping up if necessary. Then have someone else start the engine while you keep an eye on the reservoir and be ready to further top up as the level may drop quickly. Finally, with the engine idling, turn the steering about a quarter turn in each direction several times. Switch off, allow to cool again and do a final top up to the max mark. This procedure should clear any air from the system.
No-cost and worth a try I think.

*****FROM POWER STEERING SERVICES*******

jacking up the car takes the weight off the vehicle so the valve in the box wont operate correctly. as its a whine not a grumble with,i assume no loss in fluid this is un necessary to bleed the system KEEP THE WHEELS ON THE ROAD then turn lock to lock. why may the level drop quickley? a blown high pressure hose would make this happen, but the hose is ok.
sorry ,but this is NOT the way to bleed ANY car

 

[tom7035]

*****FROM POWER STEERING SERVICES*******

jacking up the car takes the weight off the vehicle so the valve in the box wont operate correctly. as its a whine not a grumble with,i assume no loss in fluid this is un necessary to bleed the system KEEP THE WHEELS ON THE ROAD then turn lock to lock. why may the level drop quickley? a blown high pressure hose would make this happen, but the hose is ok.
sorry ,but this is NOT the way to bleed ANY car

Sorry, I disagree.

 

[tom7035]

merc,like bmw use luk pumps and to put it mildly.....their crap!!

mmm..... how have Mercedes and BMW managed to survive ...........

 

[QUOMAN]

beats me tom,btw you dissagree with the way we "bleed" a self bleeding system, please tell us your viewsas, when the wheels are lifted from the ground the valve all but ceases to function

 

[Silver Arrow]

Are you certain that the drive belts are correctly tensioned?
These can cause whines when starting from cold as the load on the altenator is initally high, then drops off which reduces the tendancy to slip at higher speeds.

 

[tom7035]

beats me tom,btw you dissagree with the way we "bleed" a self bleeding system, please tell us your viewsas, when the wheels are lifted from the ground the valve all but ceases to function

My view is that the valve does not totally cease to function with the wheels off the ground. OK, supposed to self-bleed but mine was full of air when I got it 18 months ago so so much for that assumption, and I successfully carried out this procedure as I'd done on other marques for many years. It may well be it is better to do it with wheels on the ground, but have you tried turning a W124 steering lock to lock on the ground, with the engine off? (as it has to be initially). Not everyone has steering discs readily available at their back door to place under the wheels. As far as 'why should the level drop' is concerned I would have thought it obvious that when any air is expunged, the moment the engine is started to continue the process, fluid replaces the air! This DOES happen quickly therefore the reservoir level suddenly drops!
Members of the forum ask for advice and the best advice that can be given is that gleaned from one's own experiences of resolving a particular problem. It is not the place to enter into any argument.
Whine or groan, I stand by my advice to try as I suggested, It would cost nothing, take little time, would do no harm, and MAY help!

 

[QUOMAN]

how much air did you have in there !!!!! it mustve been sucking like a vacuum cleaner!! btw we dont have discs either......we have ****** big arms!! .i m not here to enter into argument, but in the 20 years i have worked ,and now manage power steering services this has never been done with the wheels off the ground, but if it worked for you then hey!
i think you may also know,from experience that that much air would create a "groaning" noise and not a whine i stand by my opinion that it is a bearing noise probably from the pump
"Members of the forum ask for advice and the best advice that can be given is that gleaned from one's own experiences of resolving a particular problem. "20 years ought to be enough!!

 

[tom7035]

i stand by my opinion that it is a bearing noise probably from the pump

Yes you may well be correct re. the pump. It's the 'accelerating while turning' which led me to think of a steering issue somewhere, or a fluid level surge. It's a bit vague and it's never easy to diagnose 'from a distance'.
Glad we haven't fallen out over the 'bleeding' issue.
I think we should let some others come in here with suggestions.
(P.S. Only 20 years? You're not even half-way yet!)

 

[fastboysparky]

Are you certain that the drive belts are correctly tensioned?
These can cause whines when starting from cold as the load on the altenator is initally high, then drops off which reduces the tendancy to slip at higher speeds.

it's not the drive belts, the noise only starts if you accelerate hard whilst cornering.

 

[fastboysparky]

is it definitely an engine noise or could it be from the drive train?

it is definately not an engine noise.

 

[fastboysparky]

Yes you may well be correct re. the pump. It's the 'accelerating while turning' which led me to think of a steering issue somewhere, or a fluid level surge. It's a bit vague and it's never easy to diagnose 'from a distance'.
Glad we haven't fallen out over the 'bleeding' issue.
I think we should let some others come in here with suggestions.
(P.S. Only 20 years? You're not even half-way yet!)

ok guys. Now you have finished. Can you translate it into laymans terms. I am only a mere sparky. I don,t even know where to check the power steering fluid. Perhaps someone could tell me where to find this first. Thanks.

 

[QUOMAN]

try calling me i`l guide you through it 020 8853 3343 ask for alan

 

[tom7035]

Don't forget to post results for the benefit of other members who may experience a similar problem.

 

[panason1c]

If i accelerate hard whilst turning when my ml is not up to temperature i get a whining noise which then stays until engine is thoroughly warm. If driven slow from cold there is no problem. Any ideas please.

Another theory.....

The auto gearbox (i assume it is an auto?) will emit a low level whine if it is starved of fluid for reasons such as a low oil level or a partially blocked filter .........A whining noise whilst accelerating hard and turning may possibly be the symptom of either of these factors.

It might be worth initally checking the gearbox atf level.

 

[QUOMAN]

we both will.......if he rings me!! cheers for a good hearted debate tom.....do it again soon?!