Alternator or poly belt noise - Benzworld.org

GreggT · 03-21-2005, 11:31 AM

01 E55
I'm getting a new noise (RPM relative) that's kind-of a cross between a buzz and a low freq whine......seems to be coming from engine front....possibly the poly-v or the alternator.

It can be heard at idle and with throttle it gets a tad louder and slightly higher pitched.

Sound familiar to anyone?.......or has experienced cost of either poly belt or alternator replacement?

TIA..........GreggT

E55pvan · 03-22-2005, 09:38 AM

A slight whine like noise is normal, my 55 has it, my old 93 400e had it, and my wifes old 98 C280 all had a similar whine like noise. I don't know where the sound comes from, maybe the water pump but in all three of my cases it is no big deal.
If yours is a new sound that just popped up then maybe you do have water pump or alternator bearing problems, get it checked out and let us know what they tell you.

GreggT · 04-04-2005, 07:23 AM

OK........it's the alternator.
Prognosis is she's about to fail.
Part cost from dealer is over $700.....plus install.

Did I say that she went off warranty month before last? [:(]

E55pvan · 04-04-2005, 10:35 AM

You probably can find a decent local MB mechanic that is less then the dealer, an alternator replacement is not all that tough to do.
A Bosch rebuilt alternator for our cars is about $300 off the net... so considering that a mechanic needs to make a living you should be able to get a rebuilt one installed parts and labor for about 5 to 6 hundred.