Whine- Seemingly from Engine

[Brundle25]

Hi All

My Rev 5 Mk 2, emits a whine that i had mistakenly put down to the Stereo interference (it still continued after stereo completely unplugged).
It appears to be from the engine bay and i can only think it could be the Alternator.
The whine is present from the car being stationary and driving at slow speed, but as the engine noise becomes louder, the whine is drowned out.
Has anyone else experienced a degree of whine from the engine bay? Could the alternator be on the way out?

[shinny]

Does the whine change in pitch with road speed, engine speed or neither?

[pbmr2]

the only other causes could be the AC idler pulley or the water pump.

As said above, if you are at speed and dip the clutch, can the sound still be heard?

Wheel bearings can whine but do so with road speed and tend to get louder with more speed.

you can test the alternator by removing the belt and checking for play in the shaft. A lot easier than taking it right out.
Also worth testing the better terminals with a multimeter whit the engine running. should be 14.4v at idle.

Also I've heard these cars moan/trumpet when they overheat. they normally steam at the same time though. are the temps ok?

[Brundle25]

Temperatures are fine. Noise stays same if you dip the clutch, however if you rev the engine when stationary the noise does increase with the revs.

[HughesR1]

It will more than likely be the alternator. My current rev5 has been doing it for 2 years, and my old rev2 did it also before it started smoking and failed.

I was meant to change it 2 years ago but as my commute is only 1 mile and I have spare cars if it breaks down I've just never got round it. Its done 4 trackdays since then aswell!

(Can't usually hear it over the whining coming from the passenger seat anyway )

[Brundle25]

Thanks for the responses! it'll be a new Alternator then. Looking forward to hearing the engine without the constant whine!

[pbmr2]

how about proving it first before buying parts?

[cosmos]

Could it be a dry bearing such as the cam belt tensioner.