How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask MB Paul Your Own Question

MB Paul
MB Paul, Mercedes Technician
Category: Mercedes
Satisfied Customers: 4317
Experience:  Mercedes Benz Qualified Diagnostic Technician
15777119
Type Your Mercedes Question Here...
MB Paul is online now

I have a 2006 56 E280 petrol. There is a whine from the engine

Customer Question

I have a 2006 '56 E280 petrol. There is a whine from the engine which is engine-speed related, so it's not the gearbox.

I have had the drive belt guide pulleys replaced, but that has had no effect. I suspect alternator or water pump bearings, but would welcome a professional opinion and advice about how to eliminate this.
Many thanks,
Robert Knight
Submitted: 3 years ago.
Category: Mercedes
Expert:  MB Paul replied 3 years ago.

MB Paul :

Hi Robert, noises can be tricky to identify and in the first instance I would remove the V belt to see if the noise does go away when running the engine breifly with the belt removed.

MB Paul :

The idler or tensioner pulleys are the most common problems so at least you have eliminated these

MB Paul :

We also see problems with the alternator, water pump or the AC compressor - with the idler pulleys you can usually feel if these are worn by spinning them by hand, the other drives are usually less obvious but do try spinning each in turn to see if any feel rough when spinning them

MB Paul :

If the noise has gone with the belt removed and you cannot identify which one is at fault by hand then the belt will need to be refitted and I would next recommend using an automotive stethoscope to help pinpoint the noise. These are fairly inexpensive and although I prefer a good quality electronic one the standard cheaper versions can be very helpful in tracing noises

MB Paul :

Here are a selection of these: Automotive Stethoscopes

MB Paul :

Trying to pinpoint the noise without one of these is very difficult - a long screwdriver to the ear pressed against each drive in turn or a long piece of vacuum tube in the ear can also be usefull but a correct stethoscope is really the best tool to use for identifying noises

MB Paul :

Best regards, Paul

What Customers are Saying:

 
 
 
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
< Previous | Next >
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C.
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex
 
 
 

Meet The Experts:

 
 
 
  • Matt

    Matt

    Mechanical Engineer

    Satisfied Customers:

    482
    BEng hons Mech engineering, in auto industry 22 years
< Last | Next >
  • http://ww2.justanswer.com/uploads/35/350matt/2012-6-7_182356_matsavatr.64x64.jpg Matt's Avatar

    Matt

    Mechanical Engineer

    Satisfied Customers:

    482
    BEng hons Mech engineering, in auto industry 22 years
  • http://ww2.justanswer.com/uploads/EU/eurotec/2012-6-11_13153_mpjaphoto.64x64.JPG Marty's Avatar

    Marty

    ASE Certified Technician

    Satisfied Customers:

    21371
    Bosch Certified Master Technician with over 35 years experience in the automotive industry.
  • http://ww2.justanswer.com/uploads/MI/mikeamechanic/2013-4-2_175558_photo.64x64.JPG mike_a_mechanic's Avatar

    mike_a_mechanic

    Mercedes Mechanic

    Satisfied Customers:

    116
    17 years experience as a auto mechanic, foreign and domestic.5 years running my own repair business.
  • http://ww2.justanswer.com/uploads/MB/MBpaul/2013-8-21_204936_paul.64x64.jpg MB Paul's Avatar

    MB Paul

    Mercedes Technician

    Satisfied Customers:

    212
    Mercedes Benz Qualified Diagnostic Technician
  • http://ww2.justanswer.com/uploads/IN/indytech/2013-8-8_102717_SantoDomingo146598x6402.64x64.jpg Greg's Avatar

    Greg

    Technician

    Satisfied Customers:

    1080
    Automotive diagnostic tech
  • http://ww2.justanswer.com/uploads/TE/techmachine/0601821347169_717372168_8940977_39623330_o.64x64.jpg Ross's Avatar

    Ross

    Diagnostic and repair technician

    Satisfied Customers:

    453
    Licensed diagnostic and repair technician