whistle sound from the auxiliary belt area

[1998K]

I hear a sort of whistle coming from the engine ausiliary belt on my W203 C270cdi. Mainly as soon started the car, dealer said should be some bearing or the free wheel of the alternator (they said that sometimes it happen), but due to the fact that the whistle is no loud they can't be more precise, so I should no worry .
Do you have any personal experience or suggestion? My car have only 30000km, it's a '03 car.

Thanks so much

Marco

 

[iamamanc]

my alternator was whistling. Checked the output and it was a lot lower than it should be changed the alternator. No more whistling
I would get the alternator output checked
Cheers
Adrian

 

[Dieselman]

It could be the drive pulley for the alternator. try unslipping the belt to see if it goes away just to eliminate anything else.
The pulley is available as a part.

 

[1998K]

my alternator was whistling. Checked the output and it was a lot lower than it should be changed the alternator. No more whistling
I would get the alternator output checked
Cheers
Adrian

thanks a lot, please what do you intend as "checked the output", do you mean the voltage if it's correct?

 

[1998K]

It could be the drive pulley for the alternator. try unslipping the belt to see if it goes away just to eliminate anything else.
The pulley is available as a part.

Thanks I'll try as soon I'll find out how to remove the belt, do you know if it's similar procedure as per the W202 auxiliary belt removal? (I've done it, and I remember I only need to operate with a spanner the tensioner pulley).

but but, removing the belt all the auxiliary are stopped so may be the noise may be produced from another pulley (water pump, AC compressor,...), don't it?

thanks again

PS: could you confirm that after this test I don't need to reset any ECU/dashboard allarm passing to the dealership?

 

[Ted]

If it's definitely a whistle, I'd go with what iamamanc said. Alternators can whistle a bit, but this can get louder if the alternator goes faulty. What happens when you turn a ll the electrics (main beam, hrw etc) if it gets a lot louder this points towards the alternator.
If it's a screech, it could just be a loose/worn drive belt. These are most likely to screech just after startup, as there is more alternator load putting charge back into the battery from the starter drain.

 

[1998K]

thanks Ted.

I'll check what happens turning all the electrics!

 

[iamamanc]

thanks a lot, please what do you intend as "checked the output", do you mean the voltage if it's correct?

Yes, most garages will have a voltage meter to check that there is enough output

 

[1998K]

Yes, most garages will have a voltage meter to check that there is enough output

since I've a multimiter do you know exactly which value shoul I read, or I can utilize the hidden menù for the voltage, isn'it?

If I well remember I read normally 14.5 14.9 during running, is it correct?

 

[television]

since I've a multimiter do you know exactly which value shoul I read, or I can utilize the hidden menù for the voltage, isn'it?

If I well remember I read normally 14.5 14.9 during running, is it correct?

13.8 is a more normal running voltage, just over 14 is ok

 

[1998K]

dear All thanks for your help.

Just to update you, I've sprayed (with the help of a long plastic pipe) a small amount of WD40, into the alternator shaft, I mean between the pulley and the alternator case.

Now the whistle sound seems it's gone:bannana: , hoping this help

So it seems that the problem is the alternator bearing

 

[panason1c]

So it seems that the problem is the alternator bearing

Or the alternator one-way pulley

 

[television]

Or the alternator one-way pulley

On a 203 270CDI I dont think so


(Good job that I have a nice disposition)

 

[panason1c]

On a 203 270CDI I dont think so


(Good job that I have a nice disposition)

I think you're wrong!.........If you re-read 1998K's post again you will see that his MB dealer said that it could be the alternator free-wheel ............."dealer said should be some bearing or the free wheel of the alternator"...........

http://forums.mercedesclub.org.uk/showthread.php?t=23702&page=5


(Mine is of a similar disposition

 

[television]

I think you're wrong!.........If you re-read 1998K's post again you will see that his MB dealer said that it could be the alternator free-wheel ............."dealer said should be some bearing or the free wheel of the alternator"...........

Funny you had only heard of the device 2 days ago, big snag for you is that the free wheel pulley and the non free wheel pulley and held on the same way and even look the same, many people and engineers fit the fixed one.

Yes while your car does have one it was only fitted to the following.

engine 613 in the 220, 628 in the 220.
628 in the 463
628 in the 163
646 in the 211
646 in the 463
647 in the 463
648 in the 211

So please take when posting these things , thank you

 

[panason1c]

Funny you had only heard of the device 2 days ago

Even funnier is that, until recently, you'd also never heard of a clutch on a free-wheel pulley!!.......Also, in the same post, (see link below) you made a ridiculous statement that ..."noise on the front end is always the idler"......Total rubbish!.........what about water pump bearings or timing chain rattle, etc, etc..........To state that front end noise is ALWAYS the idler is plain dumb!

Post #5 in the link below. ..... ..........

http://forums.mercedesclub.org.uk/showthread.php?t=23702


Television...post #5.......
....Sorry but I will stick my neck out and say no such thing as a clutch on an alternator.

The delivery rate is controlled by the regulator that recieves its info from the exciter wire.

The alternator is only ever replaced when the bearings or coils fail, and that is hardly ever and very rare. the £20 reg pack is all that is required should the charge rate stop.

Noise on the froint end of the engine is always the idler.

Malcolm
__________________
Malcolm

SL500 with everything and very nice valve caps

 

[MBManInKen]

Is it really necessary to dig up old stuff from another forum? People try to be helpful, they will make mistakes sometimes. That's life. Can't that be dealt with in a more constructive way?

 

[television]

Is it really necessary to dig up old stuff from another forum? People try to be helpful, they will make mistakes sometimes. That's life. Can't that be dealt with in a more constructive way?

Thank you very much for this post, Yes, Panosonic has joined threads with the only purpose to discredit me, and added no useful content to the post.

My answer in post 15 is correct to the best of my knowledge and the 203's have a normal pulley.

If I am wrong then I always say sorry.

 

[panason1c]

Panosonic has joined threads with the only purpose to discredit me, and added no useful content to the post

You really are a sad, old and obviously lonely man if that is what you think!.........get rid of your computer and get a life!

 

[bolide]

Does anyone know how to contact the moderators on this forum?