Clutch noisy at idle ?!

[DamirGTI 342]

Right , having some "whirr" and "clatter" noise coming from the clutch or the gearbox .

 

Fitted bigger 215mm Motronic flywheel along with the 215mm clutch , it's used Sachs clutch kit/set ... but said it was barely in use , and true it looked really good upon inspection before fitting - pressure plate and clutch disk looked like brand new with no visible signs of wear on either part .

 

But just to be safe , as the plastic prongs on the release bearing (which hooks the bearing on the clutch fork) where a little bit chipped off on the corners i didn't want to risk and bought new release bearing made by LUK , to be fitted with that used Sachs clutch .

 

Gearbox is an Mi16 , i stripped it down before fitment too .. inspected all the bearings , synchros , gears , diff etc. - also , all looked and felt fine with no "wobbly" bearings , grooves on the tapered bearings , chipped synchros ... seemed like good , low mileage gearbox .

 

Clutch fitted with all the needed areas lubricated/greased .

 

First few miles all was good/silent ... but then after maybe 200/300km's of driving , just slight spinning/whirring sound appeared at idle with the clutch pedal released .. as i press and hold the clutch pedal down it stops instantly . Or pres and release a few times and then it's silent even with the clutch pedal released , for a while , then it starts to be noisy again if left idling for a while . It's kinda "intermittent" , some days is more noisy some days less .

 

Seems/sounds to me just like dried out bearing (without grease ..) ... tried to adjust the clutch cable to give more/less preload on the release bearing but , really not much difference ... it did quiet down some , but not much .

 

Now , with a bit more mileage covered , it's progressively more noisy with the "whirring" and some "clatter" noise as well .. and always just in neutral , at idle with the pedal released , press the pedal - stops .

Absolutely no weird sounds while driving in either gear , shifting up or down , engaging/disengaging while driving - all fine .

 

Me thinks bad release bearing , but not so sure how can a brand new release bearing be faulty and so quick ? .. though , anything is possible these days .

 

Can this be gearbox input shaft bearing by any chance ? or clutch disc springs ? ... guess that would be noisy while driving as well .

 

Or perhaps , LUK release bearing for some odd reason doesn't work good in combo with the Sachs pressure plate + disc ?!

 

 

Thanks !

D

 

 

 

 

 

 

[Tom Fenton 1,542]

Sounds like the input shaft bearing chattering. When you push the clutch the input shaft stops and so does the noise.

Sometimes when you press release the clutch a few times the bearing stops making a noise.

Ive had lots of BE gearboxes do this to me over the years, none has ever got any better or worse or caused me a problem. My wife’s Getrag 6 speed box in her Mini Cooper S sometimes does the same thing.

[DamirGTI 342]

Tapered input shaft bearings ?

Interesting , they've looked fine to me when i had gearbox in bits (didn't strip the shafts totally into bits though) ... both top/bottom input shaft bearings needles , cage and cones - haven't seen/spotted any visible wear on either of those . 

 

Had four boxes on/off before on this 205 , one BE1 and three BE3's and neither one of them didn't make such noise/sound ... not saying that this one might be bad , especially because it was of unknown condition to me i decided to open it for inspection .

 

Dunno what chances might've been that i ended up with defected new release bearing ?!?

Ordered another new one , Sachs this time , but now i'm not even sure if i want to go thought the hassle of fitting that one if it doesn't make any difference/fix the issue ...

 

 

D

 

 

[Ozymandis 97]

First motion shaft bearings give the symptoms You describe.

[DamirGTI 342]

Crap ! :/ .. how unfortunate , was pretty sure it was a good gearbox after inspection of the internals .. and as said found nothing wrong visually and by feel too .

 

Only thing which was "wrong" , was loosen fifth gear nut (fifth gear on the input shaft) .. so , maybe that made some damage to the bearings ?!  
If i was to know that at the time i could've replaced those bearings while i had the gearbox opened .

 

Strange thing to me is , why there's no grinding/growling/whining noises whilst driving and shifting thought the gears if the input shaft bearings are bad ? possibly because they're not yet worn down to that extent ?

 

And what should one do now ? continue driving as it is now , or remove the gearbox and replace those bearings (really don't want to loose this one , as mi16 gearboxes are a bit hard to find over here)

 

Was thinking it's the release bearing , as it also spins all the time engine running being in pretty much constant contact with the pressure plate , just loaded and unloaded depending on the clutch pedal up or down  ...

So if it's gone bad and there's slack in the release bearing internals by pressing the clutch down it might quiet down held against the pressure plate tighter kinda picking up the slack inside it , and once the pedal is released and pressure is off the bearing starts making noise still spinning and possibly wobbling a bit around on the shaft and fork ?!? ..

Not sure , but that either wont be good .. if it really is faulty release bearing and falls apart it'll F*** my kinda new clutch .

 

D

Edited January 6, 2020 by DamirGTI

[PhilNW 44]

What was the preload on the input shaft/bearings like?

 

Just overhauled a BE3 box and changed input shaft bearings and needed re-shimming to get right preload 

[DamirGTI 342]

From what i remember , preload was measured ok. within specs. ... i haven't done the new bearings on that gearbox , as sad because all of them looked and felt good .. as well as the rest of the gearbox , just a tiny bit of wear on the synchro rings and reverse gear but that is to be expected ..

 

Overall seemed like pretty good box , that's why i'm kinda surprised by this noise ... and leaning more on the bad/defective release bearing .

 

Only thing i'm not sure , which clutch fork i fitted in ?! ... as originally the gearbox was fitted with the pull fork , rather than push , which i needed for my clutch kit to be push type ...

So i took one push fork out of my other spare gearboxes and fitted that one instead , along with the white fork bushes ... but i didn't check if it was for the yellow or the white fork bushes so i might've miss that bit .

If it's that , mixed up wrong fork and bush combination , that might be wearing the release bearing prematurely .

 

Anyhow i'll take it apart as i'm curious to see what's up .. and really do not want to lose this gearbox nor the clutch either , if it really is gearbox issue i have a few other spare ones to fit rather than driving with this one and damage it for the sake of few quid's worth new bearings .

 

D

[welshpug 1,661]

yellow bush type fork has a J stamped in the top of the shaft, so visible without dismantling

[DamirGTI 342]

On the top where the clutch arm goes on the shaft right ? :

 

 

... was thinking the marking is on the middle of the shaft on the upper fork "finger", as i found in one of your pictures posted :

 

 

 

D

 

Edited January 7, 2020 by DamirGTI