Hi all!
On my R52 cooper s..
I have a squeaking/ringing from the serpentine belt area
Today I took off the belt to check if any pulleys have any play in them.
The tensioner pulley seems to have a little movement, I'm not sure if this is normal or it that's the culprit
I'll try and post a video...

Was trying to work out if the bottom (ac compressor?)pulley also had a bit of play, but again not too sure
I'm thinking to change the tensioner first and see if this resolves it, is that best idea?

eBay has some new Gates tensioners for about £90 I think
Edit: also seen 'INA' brand, any good? Little bit cheaper

Funny thing is, put the belt back on and now it's not squeaking, but didn't have time to run it for long so I'll check tomorrow (wish I had a garage, these dark days are rubbish)

 

The squeak soon came back 😁


Video in case anyone recognises the type of mouse I have hiding in there

 

Would swap in a new belt and then a new tensioner if the belt didn't clear up the noise. That said there should not be any discernible play / rattle in the tensioner pulley. The ringing you're hearing is likely the tensioner dampener being shot, which is the little shock absorber that sits on the tensioner. It can be purchased separately and installed with some finesse (and small hands) but a new tensioner comes with a new one of those already.

INA is a BMW and MINI OEM source manufacturer for this and other parts so it should be fine.

Guessing with the belt off you already checked:
>alternator
>idler pulley
>supercharger / water pump drive pulley

for any bearing noise / feel, binding rattle etc.

Is the crankshaft pulley / harmonic balancer the original one to the car? May not be the issue at hand but "while you're in there" a good one to swap out the factory one for an ATI or SFI at any mileage; notorious for the vulcanized rubber inside separating, neatly liberating the belt drive pulley from the crank shaft. Won't ruin the motor but it will likely leave you stranded. Mine let go less than a mile from home so I was lucky.

https://www.rockauto.com/en/catalog/...r+damper,11663

https://www.summitracing.com/parts/a.../mini#overview

 

Thanks for the reply
The only really noticeable thing was the slight movement in the Tensioner pulley.
I've got a gates kit on order, with tensioner/belt/idler

Though it was worth the extra few £ and couple of minutes work while changing the tensioner.
Hopefully this will stop the noise...

Yeah I'd seen that the crankshaft pulley can fail
It felt/looked pretty solid when checking but it's hard to tell while in situ.
​​​​​​ Understand that ideally it would get changed but might have to wait a little bit longer from a financial perspective!
Not a big job to access it and change by the looks of it.

 

Hi, though I'd update for what its worth...

Spent a couple of hours changing the tensioner, idler pulley and belt today
Ran the car for a bit, it 'seems' the sound has gone, but I'll take the car out tomorrow for a bit and we'll see for sure...

Hoping that's one thing to tick off the list
I'll be happy if it's sorted as I'm no mechanic!

It's a pig to get that tensioner out
Looks loose but then you try and pull it out...

Upon inspecting the old parts after removing them, the dampener doesn't appear to be functioning much at all. Also, the old idler pulley definitely feels a bit rough when you spin it, couldn't notice this when on the car.

 

You are now.

 

Having just replaced my belt, idler, tensioner, and harmonic balancer after my idler pulley froze and chewed up the belt, I was just going to chime in that the idler pulley is a good place to start. I had an intermittent chirp, and at 131k and 21 years it was time. So I bought all the aforementioned parts, but before I could get the HB puller from WMW the idler seized. If I were going to blindly throw parts at a squeak without throwing the kitchen sink at it, I think I’d start with the idler. Cheaper and far easier than the tensioner... which must be a real bear if the harmonic balancer is in the way.