Hello everyone, I just did a whole bunch of work to my 2013 R56 Cooper S. I did timing chain, crank pully, friction wheel, water pump, water pump pulley, and some other stuff.

Anyways, my friction gear seems to be bouncing/rattling ever so slightly on the belt and water pump pulley.

The Belt is the ECS tuning kevlar reinforced belt 895, and the friction wheel is dayco and brand new. I did not put a new belt tensioner in.

So far it is seeming like maybe the friction wheel isnt pressing against the belt hard enough or the belt has imperfections on the friction side causing the friction wheel to bounce.

Does anyone have any experience with the @ECSTuning kevlar reinforced belt? Has anyone had a new friction gear just been a dud?

I read another thread where his friction gear was loose and it was brand new just like mine so im not sure whats going on here.

Check out this video, https://drive.google.com/file/d/10qk...ew?usp=sharing

I think it may be a bad friction wheel.

 

@CakeEater
It best to use both the friction wheel and tensioner as OEM due to tighter tolerances and I suggest using “Gates” belt as I have very good experiences with them.

 

Dayco is OEM for both the friction wheel and the tensioner. I did not replace the tensioner. The Belt is an 895mm ECS belt, which might have imperfections in the red friction surface causing the friction gear to bounce. I am thinking of throwing my old belt back on for testing, it is a continental 894 all black. But i am also thinking this friction gear bearing is bad.

 

I'm not able to watch the video as I do not have a Google account.

Does the friction wheel rattle while the water pump is driven? Is the water pump driven properly or is there slippage between any of the pulleys and the friction wheel?

When the water pump is not driven, the pressure of the friction wheel on the crank pulley is by design such that the friction wheel is free to bounce if the belt surface it is running on is uneven.

If the friction wheel is turning smoothly and quietly when pressed (in order to simulate load) and turned by hand, then it is (extremely!) unlikely that the bearing is the cause of rattling.

FWIW: Here is my "excursion" with a rattling friction wheel, including videos at different stages (i.e. strong rattling due to melted rubber inside the tracks of the crank pulley and slight rattling due to an uneven surface of a new belt):
https://www.northamericanmotoring.co...ng-engine.html

Does any of my three videos come close to the rattling of your friction wheel?

 

Yes it it most like the sound in your first video. And yes when the friction gear is not tensioned it bounces off the belt. And when it is driving the water pump pulley it is less noise but still a little bouncy. It is leading me to believe it is the belt with imperfections on the friction side or the bearing in the friction gear. The water pump and water pump pulley are brand new along with the friction gear and crank pulley and belt. Its all new except the actual belt tensioner.

 

Have you tried running with the new parts but the old belt?

 

No problems with the belts or friction wheel, when you install make sure the tension is set and the cable is all the way in. When you pull that little cable in it takes the tension off the belt. We had some of the OEM/ genuine friction wheel be bad from the factory on the bearing itself. Small amount but it happens. Seems like the system is prone to be problematic due to the design of that friction wheel set up. The water pump drive wheel can wear and crack making noise on the wheel.

Can you post a shared link. I cant see that link for the video.

Make sure the old belt has the same length as the one you took off. Old one should have marking for the length.

https://www.northamericanmotoring.co...-r56-help.html

 

Not yet, i just finished putting on all these new components when i did my timing chain last friday. So next step would be to put on the old belt and see if that solves the problem.

 

I updated the link, anyone should be able to see it now with the link https://drive.google.com/file/d/10qk...ew?usp=sharing

As for the belt i took off, it was a continental 894. My car calls for an 895 and the ECS tuning kevlar reinforced belt is an 895. The 1mm difference shouldnt matter. The friction gear is brand new Dayco from ECS tuning.

I think when i put the friction gear on initially while working on the car it was in the extended position but i of course retracted the tab to engage the friction gear before starting the car. The water pump and water pump pulley are all new as well so it seems like the exterior of the ECS belt is not smooth or unlikely that the new friction gear is bad. I did spin it before putting it on and it seemed fine to me

 

Ok thanks

I just saw i another post that you have the main drive from another vendor, i dont know but maybe its off enough to not make contact or irregularities in the pulley? Never seen the belt be issues other then the factory Genuine MINI belt like to wear and get chewed up ( sometimes separate) over time, but not new. The friction wheel will make noise when its moving, but i can tell with all the other noises if the bearing on the dayco is bad from the factory/loud.. It does not look like tensioner is bouncing off the belt, maybe i dont see it.

Yea the belts are smooth, i have never seen one that's irregular unless its worn/time for change. But the main drive pulley being non oem could be making the belt do some weird things?

Let me know what you find when you swap things around.

 

At about 30 seconds in do you hear the noise that stops and starts again when i lift the friction gear off the belt? It sounds like rattling from the bearing on the friction gear imo. I really dont want to put the old one back on... I just buttoned the car back up lol. :'( I am gonna try the old belt and see what happens here like mid next week, im going out of town this week so i dont have time to troubleshoot right now unfortunately.

 

So I have the car apart again and found the issue. There was a crack in the plastic housing on the friction gear. This was vibrating against itself causing the noise. I superglued it and hopefully it will hold, if not, it is only just an annoying noise, the part works perfectly fine.


You can see here where the friction gear plastic housing has a crack. I superglued this back together

 

I was experiencing an odd noise. It sounded like an engine miss but it dissipated on acceleration. It was driving me nuts.
I couldn’t locate the source so I lifted the car onto the stands, removed passenger wheel and wheel well liner and fired it up. The noise was around the belt and pulley’s, I disengaged the friction wheel. Wow noise went away. I suspected waterpump.
the car is 13 years old and it made sense. I replaced both waterpump and while it was all torn apart changed the crossover tube, thermostat and water pump friction wheel assembly (ECS for all the replacement parts), put everything back together and the noise was still there. So I changed the crank pulley thinking that it may be off center.
that wasn’t it. I had changed the water pump pulley with the water pump so I knew that wasn’t it. In Feb I changed the tensioner and belt so I thought that couldn’t be it. I dug into every forum and I located one reference to aftermarket serpentine belt being a slightly different thickness.

That was the source of the noise, the belt. I bought an OEM belt from Mini and removed the aftermarket belt I had purchased in Feb. there was a difference in belt thickness of 1.2 mm from aftermarket to OEM.

The difference of 1.2 mm was causing the friction wheel to skip (bounce) on the belt. After all the replacements it turned out to be the belt.
the friction wheel skip sounded like an engine miss.

I should have done the OEM belt first but it didn’t dawn in me that there would be a difference and that this minor difference would have caused such a huge problem.

I hope this helps someone else

 

Posting solutions to your problems is always the best way to help the Mini community.