M103 normal sounds???

[Socrates]

I have a 300SL with the M103 engine. In addition to the splendid exhaust note there is a high pitched whiring sound - pitch correlated with engine speed - that sounds like it must be coming from something running on the front belt. It sounds remarkably like a supercharger (but I haven't got one of those honest!) Is this normal, does anyone know what it is? Can I get rid of it?
Many thanks

 

[supercharger]

well i have a supercharger on my w126 380sel and that makes a lovely sound certainly not annoying. LOL
it sounds like it could be a bearing maybe on a pulley or possibly the water pump i had a similar sound on a 320 104 engine fortunately i also had a water leak which made it easy to diagnose as the water pump.


supercharger

 

[Ian B Walker]

If fitted it could be the air pump. Location? From the front of the engine, bottom left.

 

[BlackC55]

Alternator? They can whine