Spun my crank timing gear: dealer fixes under warranty with "Grip Disc"

[kitesurfer]

Originally Posted by JoeyBananas

The last two guys who have posted they Spun their Crank Hub go MIA after they post. Kind of frustrating.

I guess the positive in all of this is according to the forums I dont think BMW has denied anyone warranty aork who has spun their Crank hub

The Other Guy who posted was Full of Shit & went MIA (to which deserves a punch in Nut Sack!), lets see if this OP comes back reports build date and posts a dealer work order or goes MIA too

[JoeFromPA]

Originally Posted by JoeyBananas

The last two guys who have posted they Spun their Crank Hub go MIA after they post. Kind of frustrating.

I guess the positive in all of this is according to the forums I dont think BMW has denied anyone warranty aork who has spun their Crank hub

Makes me wonder if they are BSing or if they are being contacted by BMW to stay silent - since there is a potential for warranty work on a modified car after all.

[mephiska]

Originally Posted by Luminous

I'm coming from the N55 world and am looking to get into an F80 but this crank hub issue gives me anxiety, I'm hoping this issue was resolved with the dec'15 revision.

Just so I understand, once the crank hub spins is the engine repairable or does it need to be replaced entirely?

Don't worry about it. Your concerns are an overeaction and a perfect example of the way enthusiast forums can cause people to freak out over a very rare fault. Get an F80 and don't give a second thought to it.

Yes it's repairable, it doesn't blow the motor (that we've seen) and the sensors are smart enough to put the car into limp mode to prevent further damage when it detects timing is out of whack.

[Bowser330]

Originally Posted by kitesurfer

The Other Guy who posted was Full of Shit & went MIA (to which deserves a punch in Nut Sack!), lets see if this OP comes back reports build date and posts a dealer work order or goes MIA too

Will be harder for this guy to go MIA seeing as he posted his phone number on the largest BMW forum on earth... hopefully it's a burner phone....

[climax_e92]

Sub'd

[Rik84]

All I'm interested in is if there is a legit new friction plate to help stop the crank hub from moving. That said - practice what you preach. I shall be turning up the boost on my car in the next few weeks and seeing wtf happens! If I spin a hub I will be the first to admit it and will definitely not run away.

[MKovac]

Guys - sorry, busy weekend. Not going MIA here just didn't get a chance to take a look at the thread. Wow, crazy response...

Originally Posted by DS_BMW

What is the peak RPM the motor reached? They should have all that info.

7600

Originally Posted by clutchdj

So you have a manual gear box?
Can you confirm whether or not motor was in sport or sport plus at the time of the hub failure?

Thank you

Sport. From what I know the quick downshifts are what backs the hub off. If I remember correctly it was a 4th-3rd rev-matched downshift done by ECU

Originally Posted by JoeyBananas

What year is your Car?

[QUOTE=Maxis;21000274]

Originally Posted by MKovac

So! It happened!

I was coming off of I-95 after some spirited driving, throwing some downshifts in sport when it happened. "Drivetrain Malfunction" pops up and boom, limp mode. Immediately furious and perplexed about the situation I pull into my friends shop and hook her up to the autologic. 3 codes pop up.


Were you still able to drive the car,,,

Yes. In limp mode.

For all of those wondering...

-It is a 6 speed.
-It is not a ZCP.
-8/15 build date

Stand by for RO....

[MKovac]

See attached for the original RO.

I removed any info that was not relevant to the fix...

[The Choosey begger]

Tuned?

[MKovac]

Originally Posted by anglo

Tuned?

[SakhirM4]

Originally Posted by MKovac

See attached for the original RO.

I removed any info that was not relevant to the fix...

The RO says that the crank hub bolt was still tight, so the hub moved without the bolt loosening?

[MKovac]

Originally Posted by SakhirM4

The RO says that the crank hub bolt was still tight, so the hub moved without the bolt loosening?

Guess so...

When it first came in they checked the torque on it and ruled the spun hub out entirely. It was not until they started to pull parts that they noticed that it was out of time.

As the OP I do have to say...

Please do not let my experience ruin your enjoyment of the f8x chassis or any performance car of that matter. So many high performance cars have engineering and or design flaws from the factory. I have learned that over time it is purely the nature of the beast. These are high-strung cars that do have weak links. We know that. Endless stories of rod bearings, vanos, subframes, etc etc. from all ///M cars from different generations. If you don't want to deal with the growing pains of a high performance german automobile I suggest you go buy a Honda. We are lucky to have a four door production car that can run circles around six figure supercars and still drop the kids off at school, all in the same day.

Go out there and enjoy your car. Drive the piss out of it.

[larryn]

Thank goodness this was an F80 6sp. I drive an F82 6sp.

Thanks to the OP for all the good info provided!

[CaryTheLabelGuy]

Thanks for the additional info OP.

At first the RO said the hub bolt was checked and was tight, but later said the bolt was not a factory torque spec. If the timing sprocket spun and damaged the friction disk, the bolt could possibly show at a lower-than-spec torque; or the bolt did infact loosen, causing the timing gear to spin. It's really hard to say what is failing first on the SCH cases. I tend to believe it's the bolt itself that is the main issue.

Also, it's worth noting that this is a pre-revised bedplate S55 (pre-Dec 15) and is ALSO a 6MT that wasn't overrevved.

OP, I have a question for you, if you don't mind clarifying for me/us.

The friction disk that they replaced appears to be the exact same part number as the original, so the washer itself doesn't appear to be different from what is already used in S55 production. Is it possible to confirm this with the tech, that in-fact, the same exact part was replaced from the original?

[JoeFromPA]

Awesome update Op. This is either the only or one of 2 6-speed cars that I've seen this happen on, though not stock.

Nice BMW update and hey, look, free alignment by BMW. What am I missing that they have to do an alignment after a crank hub replacement?

[MKovac]

Originally Posted by CaryTheLabelGuy

Thanks for the additional info OP.

At first the RO said the hub bolt was checked and was tight, but later said the bolt was not a factory torque spec. If the timing sprocket spun and damaged the friction disk, the bolt could possibly show at a lower-than-spec torque; or the bolt did infact loosen, causing the timing gear to spin. It's really hard to say what is failing first on the SCH cases. I tend to believe it's the bolt itself that is the main issue.

Also, it's worth noting that this is a pre-revised bedplate S55 (pre-Dec 15) and is ALSO a 6MT that wasn't overrevved.

OP, I have a question for you, if you don't mind clarifying for me/us.

The friction disk that they replaced appears to be the exact same part number as the original, so the washer itself doesn't appear to be different from what is already used in S55 production. Is it possible to confirm this with the tech, that in-fact, the same exact part was replaced from the original?

Thank you! Yea.. good question.

Maybe I spoke too soon and all they did was replace the washer with another of the same??? The way the shop foreman explained it to me it didn't seem to be the same part.

Originally Posted by JoeFromPA

Awesome update Op. This is either the only or one of 2 6-speed cars that I've seen this happen on, though not stock.

Nice BMW update and hey, look, free alignment by BMW. What am I missing that they have to do an alignment after a crank hub replacement?

Funny huh?

[GrussGott]

Originally Posted by YasM3

The grip disc is the same. It must be replaced when the hub spins. There is no updated or added grip disc. It is already present. I think OP just had a small miscommunication with the foreman about the grip disc and what they were actually doing. Nothing extra is added.

So the interesting question here is:

* Design flaw? (i.e., BMW spec'd a part that's not up to the task), or

* Part failure? (i.e., design is fine, however a part failed within the designed failure rate)

The answer will be known if it happens again (assuming OP puts his mods back on): if it does, it's design a flaw and everyone should totally lose their shit. If it doesn't then it's a routine part failure.

[JoeFromPA]

Originally Posted by YasM3

The grip disc is the same. It must be replaced when the hub spins. There is no updated or added grip disc. It is already present. I think OP just had a small miscommunication with the foreman about the grip disc and what they were actually doing. Nothing extra is added.

Unless someone has one of the original grip discs and new ones in their hands, it is entirely possible BMW changed the part without changing the number.

I'm not saying it's likely - just possible. They did it with S65 rod bearings for 4 iterations I believe without ever changing the part number.

[climax_e92]

Crap... mine was built a month after yours .

[idocm4]

Originally Posted by climax_e92

Crap... mine was built a month after yours .

Dude! You're so screwed! Lol.

[al3xander]

Originally Posted by JoeFromPA

Awesome update Op. This is either the only or one of 2 6-speed cars that I've seen this happen on, though not stock.

Nice BMW update and hey, look, free alignment by BMW. What am I missing that they have to do an alignment after a crank hub replacement?

The tech story states the oil pan gasket was done which usually involves dropping the subframe which is possibly why they performed an alignment after all the repairs?

not 100% on that though

[MN2///M]

Originally Posted by GrussGott

So the interesting question here is:

* Design flaw? (i.e., BMW spec'd a part that's not up to the task), or

* Part failure? (i.e., design is fine, however a part failed within the designed failure rate)

The answer will be known if it happens again (assuming OP puts his mods back on): if it does, it's design a flaw and everyone should totally lose their shit. If it doesn't then it's a routine part failure.

Or factory tool out of adjustment....tool used to torque that bolt on this car and a little bad luck; may see others, may not.