Correct me if I am wrong, but does the sound get more pronounced when I was filming near the alternator? It did not have any in/out play last time I checked. Do these alternators come with a clutch pulley or a solid one?

 

think there are some that have a clutch, but cant remember a thread where alternator bearings had gone so would be rare.

just get the belt off and hand feel all the pulleys, you will feel a bad one will spin rough or have a little side to side play.

 

Put the straw on a can of lubricating spray (not wd40 really, as it is more a degreaser),

With the engine running, spray the centre of each pulley in turn, listening for the noise getting quieter.

The noisy pulley will temporarily quieten due to fresh lubricant, but do not treat this new silence as a permanent fix.

*** Be careful when spraying the pulleys, as the belt or pulleys spinning may throw it in your eyes. ***

 

Probably a silly question but was the noise there before the belt change.

 

Not a silly question.

I remember indeed hearing a similar sound with the engine running prior to the parts change. My thinking was then that the belt and tensioner were worn and due for replacements. Unfortunately, no earlier sound recordings other than what is observed today.

 

Definately needs a closer inspection tho mate. Is the tensioner new too.

 

Yes. Fitted new belt, tensioner, and idler pulley the same day.

Lots of swearing took place while swapping out the idler pulley. Ordered a slim serpentine belt socket wrench (with crawfeet) so should be easier this time around in that minimal work area.

 

Yeah every aux belt I've ever replaced had taught me some choice words, let alone grazed knuckles and cut fingers. I'm no pro but my guess would be a bearing going/ gone on one if the old pulleys. Also check the alternator. The bearings were partially seized in my old focus and made an odd noise

 

Put the straw on a can of lubricating spray (not wd40 really, as it is more a degreaser),

With the engine running, spray the centre of each pulley in turn, listening for the noise getting quieter.

The noisy pulley will temporarily quieten due to fresh lubricant, but do not treat this new silence as a permanent fix.

*** Be careful when spraying the pulleys, as the belt or pulleys spinning may throw it in your eyes. ***

Tried what you suggested with a penetrating lubricant containing PTFE today.

Each pulley eventually got drenched with most of the directed spray concentrating on the center.

Since I am leaning towards the alternator pulley being the culprit without having taken the belt off just yet I sprayed more than enough of the lube at that particular pulley. Then switched off the engine for the fluid to creep in before starting up again 10-15min. later

Still no luck. A minute or two after letting the engine idle the same noise persists.

Have to jack the car up and check those pulleys again this weekend I guess.

 

Maybe a bearing. Not sure what engine yours has but my older focus was making a wisp wisp wisp noise when idling. Turned out the water pump was nearly seized

 

I never got around to investigating this noise problem further until last week.

Here is a new video of what may be a faulty power steering pump, and the surprising source of the tapping/knocking sound that I mistakenly suspected the alternator of causing.



Please comment whether my assumptions are correct, and what should be done about this.

 

If day the bearings have definitely gone in that mate. I'd price up a new one

 

Just the pulley or the whole pump assembly?

 

put your ear on a screwdriver, push it hard on the pump. changing the pump not to hard, pop the light out and check you have a spanner that will fit on the lower pipe nut, seem to remember i used a stubby imperial spanner as all my metric were to long. will also need a couple of turns of ptfe tape on the thread.

 

Changing pump can be very difficult. The fitting that goes into pump is often extremely tight or leaks post repair. If you damage the fittings nut it isn't as simple as replacing. The nut fitting requires splitting to remove in some cases. Google is your friend.

 

yes there have been a few threads about leaking high pressure pipe, may be that i got lucky have only replaced two and didnt take much notice of the fitting, but if there is a washer in the pump hole it may be worth replacing it before putting a new/used pump on.(probably worth a spot of oil on the fitting)

just be careful to line the pipe up square with the hole as best you can before tightening, last thing you need is a crossed thread.

 

You can gain a small amount of extra access by removing headlight. Bottom bolt is the hardest