loud high pitched ringing

[tonyjohnson]

hi everyone i am new to the club, i have a problem with my ml270cdi when on idle there is a loud high pitched ringing/sqealing noise not like a slipping belt though. It only makes this noise on idle once you pick the revs up it sounds fine, any help would be appreciated.

 

[yachtman]

hi everyone i am new to the club, i have a problem with my ml270cdi when on idle there is a loud high pitched ringing/sqealing noise not like a slipping belt though. It only makes this noise on idle once you pick the revs up it sounds fine, any help would be appreciated.

is it eminating from the alternator area? alternator free wheel sprag pulley if fitted?

welcome to the forum

 

[walsi]

Hi ya, my vito had the same problem when i bought it except it didnt go away as you reved the engine so sounded like a supercharger, that was a bearing on either the altenator or the idler pulley. I dont know which one it was because i lubed all and everything i could see but it went away and never came back and that was 140,000 miles ago so there is a fair chance it could be.

Cheers Martin

 

[ringway]

Hi ya, my vito had the same problem when i bought it except it didnt go away as you reved the engine so sounded like a supercharger, that was a bearing on either the altenator or the idler pulley. I dont know which one it was because i lubed all and everything i could see but it went away and never came back and that was 140,000 miles ago so there is a fair chance it could be.

Cheers Martin

That's interesting.

I'm just about to replace the alternator on the Sprinter.

The whining noise follows the rev pattern up and down.

Thread about it HERE.

Regards,

Paul.

 

[walsi]

I would check the idler pulley because they do fail and if you have been through a lot water it could just be dry bearings. Its worth a go because its free although on the vito it was a b***h to do because there isnt a lot of room to get your hands and a can of spray lube in there

Cheers Martin

 

[tonyjohnson]

thanks for info i will get it a little spray in the morning. i have spent most of today servicing and cleaning the engine bay i will get a pick up in a little while.

 

[ringway]

Hi ya, my vito had the same problem when i bought it except it didnt go away as you reved the engine so sounded like a supercharger, that was a bearing on either the altenator or the idler pulley. I dont know which one it was because i lubed all and everything i could see but it went away and never came back and that was 140,000 miles ago so there is a fair chance it could be.

Cheers Martin

Thanks Martin,

I've lubricated the alternator and idler pulley (as best as I could) but the whining still remains. Worth a go though.

Having had a look around the web I'm more inclined to think that it is more likely to be the idler pulley than the alternator.

Cheers,

Paul.