Squeaky noise coming from alternator area?

[oxs1]

I am getting a squeky noise coming from the alternator area. Can it be the bearings or do i have to change it?

[HeavyDuty]

Try to narrow it down to see if it is the alternator and not an idler pulley first.

[oxs1]

As my rms rise the noise gets louder. And sometimes when i rev the engine you can hear it and it kinda sounds like the power steering squeak.

[90Q45blue]

It's either a belt or an idler pulley. If you can record the sound and post it here, we could probably narrow it down for you. Or you can just take it to a local mechanic and have them take a listen. The belts and idler pulleys are simple jobs any mechanic can handle.

Nick

[Q45tech]

Sound is just a vibration you can hear..........it's frequency is above 45 HERTZ.

If you know the exact rpm and exact frequency [of vibration] you easily can reverse calculate the exact diameter of what ever is causing the sound/vibration.

Unfortunately a squeel is a complex sound and not a pure tone so you need to display the sound on a spectrum analyser and grapple with the various amplitude peaks.

Or just learn the sounds of pullies and bearings and identify the location with a technicans stethoscope [a thin probe is attached].

[HeavyDuty]

Yeah.....

Sorry I was in a hurry this morning & meant to also type this:

DCB method:

Remove the belts, leaving the innermost one on, start the car & see if you hear the offending noise. If not, remove the inner belt & attach the next outer one, repeat until you determine exactly where it's coming from.

*Obviously* don't leave the car running for more than a few seconds or so while doing this test. It may not narrow them down one at a time, but narrow the grouping somewhat.

[Jesda]

If you know the exact rpm and exact frequency [of vibration] you easily can reverse calculate the exact diameter of what ever is causing the sound/vibration.

Now THATS cool info!

As far as my squeal, in the exact same situations in described, it ended up being the water pump.