This feels like the sort of issue I should know off the top of my head by now, but, lemme check... nope. Nothing there.
A while back the Mini had an oil leak that ran onto and killed a couple of engine mounts. Took me longer to get fixed than it should've, and I've blamed a judder (chatter, perhaps?) on taking off in 1st on that episode causing a funny wear pattern, but many months after having replaced the mounts, it still does it. I was hoping that having the motor firmly mounted would cause a fairly quick re-wear-in of whatever had happened, but no... (I'm pretty darn certain said oil leak never got anywhere near a friction surface)
I was resigning myself to the notion that the clutch may just be dying. It doesn't slip, but when you've got a clutch that misbehaves with 106k miles on it, what do you really do other than replace it?
Then Trent mentioned that BMW dual-mass flywheel failures seem to be A Thing. Like so many things, this was news to me. Anybody know anything? A quick search suggests to me some symptoms that I'm not having; rattling, clunking... OTOH, apparently they can't be surfaced and some regard them as just a thing you replace when you do the clutch, which does not thrill me at $800+ for just the flywheel. But if that's it, that's it.
So...
- Anybody have further info on whether this feels like a dual-mass flywheel failure?
- Anybody want to tell me to just replace the dang flywheel at this point since it's probably past it's best by and comprises half the problematic friction surfaces?
I think I know my course of action, but I'm still curious about things I should know about dual-mass flywheels in general.
I've had clutch shudders before and I blamed it on concentricity or deposit issues much like brake rotors
I'm interested to hear the real answer
LUK is a key competitor but I also know that they publish some great technical literature.
It might be more in depth then you want to go but in summary chatter (judder) is normally attributed to either the friction material properties or geometric issues.
Review pages 23-45 for a detailed explanation. The link should take you to the 6th LUK Symposium technical pages.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwizzvjOwYuHAxXZJzQIHXJ_ADsQFnoECBIQAQ&url=https%3A%2F%2Fwww.schaeffler.com%2Fremotemedien%2Fmedia%2F_shared_media%2F08_media_library%2F01_publications%2Fschaeffler_2%2Fsymposia_1%2Fdownloads_11%2FluK_kolloquium_en.pdf&usg=AOvVaw2LPGqviIXgpJys4Ni0RwpY&opi=89978449
In regards to the DMF at 106k miles I am afraid replacement is likely in order. Resurfacing isn't practical as there is no way to support the friction surface portion of the flywheel except through the sprung mass system which has varying degrees of either axial or rotational "slop" in the system due to design and wear.
In reply to fusion66 :
Thank you!
Too far down the rabbit hole is my favorite place.
And it's worth it just for this illustration. That's me!
What Mini do you have? If it's a first gen you can buy an aftermarket clutch kit from Valeo that includes a solid flywheel, clutch disc, pressure plate and release bearing for about 1/2 or less than the OEM stuff, and they work beautifully. Significantly less pedal pressure and smooth as buttah.......I've done several and the highest mileage one currently is close to 100K with no issues......he says it still feels like a Honda clutch!
If you wind up pulling the gearbox to change it, be sure to remove the shift cables and clean and lube them - or replace if you prefer. Early cables were prone to getting water in them and rusting or freezing in the winter - ask me how I know!
Also carefully check the tube that the release bearing slides on, it's made of plastic and they break. There are aftermarket metal ones available that don't break.
Lastly you either need to buy or make a clutch bleed tool - you won't get a good pedal unless you do, there are lots of instructions online on how to make the tool and it's neither hard nor expensive.
In reply to MiniDave :
Thank you! I should've said... It's an F55/3rd gen modern Mini.
Don't know why people forget to tell us what year and model they're working on - it makes a difference for getting the right info, doesn't it?
I don't know if Valeo makes a kit for the F series cars, but since those are BMW based, seems like there should be an aftermarket solution out there.
Good luck!
The dual mass unit developing wobble play is probably responsible for judder. The half that the pressure plate bolts to, that also contains the friction surface, has to have damped rotational play for it to work, and as the joining surfaces wear, it can wobble around off axis, which can make smooth engagement difficult.
I had a 1.8t Audi that had a couple degrees of wobble! We installed a SMF from a TDI due to cost, and personally I didn't like it, but the customer was happy with the savings.
In reply to MiniDave :
I should have included it on general principle, you're right, but I came in with the impression that BMW/Mini dual mass flywheels were A Thing, and that the discussion would be around that entire family and its characteristic issues. But again, it's silly not to mention the patient's details.
