Hi guys, i just picked this car up and it is my first Benz-i love it. I have noticed a bit of a whirring sound when the engine runs. Is this normal for one of these pups? Perhaps a normal sound due to a timing chain not a belt etc? If this is not normal then what could this be? Any pointers would be greatly appreciated. Motor runs great.

There is a vacuum leak somewhere behind the heater controls.
Ned, If you in Australia, here's some info for you.

(a) Go to http://ww.ozbenz.net/ and ask your questions there. Oz specced cars are slightly different from Euro and U.S. models.

(b) Watch out in Glenrowan

Bewdy mate, thanks for that. This is the MB Aust guys isn't it? I got some gear from them the other day, great bunch of guys. I registered on the site but my activating email hasn't come through yet, perhaps a christmas shut down thing?

I would guess that the whirr is from the idler pully on the belt tensioner. I had a similar situation on an '88 300E. New pully fixed it.

Rgds,
Chris W.

Thanks for that, i'll check it out when it stops raining. It's a pretty loud whirr and i am now starting to think it may be the PS pump. Are these a difficult/costly thing to replace? My engine is an M103 and the pump has that silver cylinder resevoir if that helps identify it.

AS mentioned above Most likely its the belt tensioner pulley on a failing tensioner .As the rubber in the tensioner collapses the pulley runs askew and the bearings fail . yes its quite loud and ominous sounding.suggest replacing the belt as well due to one side wear it causes
mak

Hmmmm, i had a look at this wheel and it seems to run straight. The sound is quite a definate whrrr that reacts to engine speed. Man I hope it isnlt anything expensive!!!???

The easiest way to find the source of the noise is to use a car stethoscope.
They are very cheap, just a few $.

Do not use screwdrivers or sticks, if you hold them to your ear you can’t see if they touch a moving part!

Be very careful, don not touch anything moving!!
And of course do not wear any loose clothing, scarf’s etc!!!!!!!

Rob