Duratec he idle noise

[jjmaia]

Hi all
Wonder if anyone can help me identify the meaning of this noise while in idle? When I press the throttle it goes away.

https://youtu.be/QTofdX5UpcA

Thanks

[E-bmw]

Perhaps you should describe to us what you think is not right as that sounds fairly normal to me.

[GreenV8S]

Listening to a running engine with the bonnet open is a sure fire way to convince yourself there's a problem. Can you hear the noise from inside the vehicle with the bonnet closed?

[jjmaia]

Yes, I can from the inside, and its less audible.
I never heard this kind of humming from an engine.

[S0 What]

Sounds like a bearing to me

[jjmaia]

S0 What said:

Sounds like a bearing to me

Strange as the sound comes from posited the belt...

[GreenV8S]

I can't really hear anything from that video, but an idler pulley bearing would be in the sort of area you're pointing at.

[Dogma1978]

I had exactly the same engine and that's not normal sounding. It sounds very much like the alternator going. The thermostat housing imsits directly above it. If it leaks it runs into the alternator. If it's not that I'd hazard a guess it's the water pump bearings failing

Edited by Dogma1978 on Thursday 16th March 00:31

[Mignon]

I can hear a frequency in that noise that coincides with the markings on the auxiliary belt passing over the pulley so I suspect it's a bearing in something at that end of the engine.

[Dogma1978]

The HE lump has two belts. The front upper one is easy to remove, you could easily remove and check the bearings for play and noise. The lower one is a pig job and you need the correct tool to remove and replace the belt. At idle turn on something that puts a load on the alternator such as heated screens etc. Does the noise stay or go ?

[jjmaia]

The belt and thermostat were replaced in October.
I will try and put a load to check if the sound increase.
Thanks.

[jjmaia]

Its does makes more noise while in load:

https://www.youtube.com/watch?v=E7QhlmSM0rI&fe...

[GreenV8S]

That high pitched warbling noise sounds unusual - I assume that's what you're referring to. It sounds rather like a running bearing. A mechanic's stethoscope might enable you to track down the source. Somebody familiar with working on the engine could probably guess where it's coming from, and unless you're planning to fix it yourself I suggest that you ask your preferred garage to have a listen and see what they suggest to fix it.

[Dogma1978]

I agree. Personally I'm still betting on the alternator. The sound is near identical that mine made. The grease from the bearings had gone and they had slowly worn away. But I'd get that check asap. Either way you don't want to be stranded if it fails completely

[jjmaia]

Problem is that I don't have a preferred garage :/
Will have to try to sort one.

Thank you for your help.

EDIT: had a work colleague looking at the video and he says it could be the the belt? He says a bearing would have more of a rattle?

Edited by jjmaia on Friday 17th March 12:57

[S0 What]

jjmaia said:

Problem is that I don't have a preferred garage :/
Will have to try to sort one.

Thank you for your help.

EDIT: had a work colleague looking at the video and he says it could be the the belt? He says a bearing would have more of a rattle?

Edited by jjmaia on Friday 17th March 12:57

Still sounds like a bearing to me, when dry the drone, when loose they rattle, it sounds like the aux belt idler but without being there i cant really tell, no one can from a video, take it to a garage, by the time you get answer on here the thing could have self destructed and cost you more money, stop faffing about and get it looked at by a propper mechanic not a bunch of (obv) deaf internet heros.

[jjmaia]

I plan on doing it today, but there's nothing I can do before work.
Thanks.