540 clutch job question.

[bbig119]

How common does the flywheel need to be replaced when doing a clutch job?

Also, I have conflicting opinions from three different people. Two suggested that I replace the rear engine seal, during the clutch job, and the third thought that it should be done only if necessary. He told me that theres a risk of creating problems with a flywheel that doesn't need replacing if its removed to replace the engine seal(as preventative maintence).

[Jehu]

it would seem to me anything that was put together should be able to be taken apart without destroying the design to replace parts. What's your clutch doing that makes you believe it needs replacing?

[bbig119]

Its slipping badly. I think its got almost 100k on it since the swap.

I posted a while back about the cost of a clutch job (http://www.bimmer.info/forum/showthread.php?t=26729&highlight=clutch).

The slipping has only gotten worse and I'm not having to be careful when accelerating not to let the rpms shoot up too high. Even being careful, usually it'll slip in every gear but 1st at this point.

[Dave M]

How common does the flywheel need to be replaced when doing a clutch job?

Also, I have conflicting opinions from three different people. Two suggested that I replace the rear engine seal, during the clutch job, and the third thought that it should be done only if necessary. He told me that theres a risk of creating problems with a flywheel that doesn't need replacing if its removed to replace the engine seal(as preventative maintence).

Unlikely your flywheel needs to be replaced. Is it a dual mass flywheel? Either way, its just a big (expensive) hunk of metal that wears very slowly relative to clutches and pressure plates. Probably a bit of a difference b/w the wear rate on a 540 and M50 525, but my original flywheel is still kicking after 500k km.

In terms of removing and replacing, not a problem. Bentleys only suggests that you mark its position on the end of the crankshaft and make sure you hang it on the same dowels. I didn't do this, took my 33% chance and have no balance issues.

I wouldn't do a clutch job without replacing the rear main seal and pilot bearing and tranny output shaft seal and linkage bushings and guibo and center bearing and exhaust hangers and....... just kidding :) , but consider replacing some or all of these items if its been a while

Dave M

[31Hertz]

The clutch and flywheel were both replaced in my car by the PO. I have no indication as to why the flywheel was replaced at the same time, but it's a $550.00 part, so I ain't complainin'... It seems like I have read some discussion on here about the possibility of resurfacing...
http://www.bimmer.info/forum/showthread.php?t=17644&highlight=dual+mass+flywheel+resurface

[Chris'91'525i]

If you use your present Flywheel, it's a good idea to scuff up the surface of flywheel that comes into contact with the clutch disk, to removed the glazed surface.
Clutch will be much smoother when engaging it. The glazed surface will tend to want to grab.
I use a Flex-hone on both brake rotors and flywheels for this purpose, these work the best and the fastest.
Those 3" Roto-lock, course sanding discs from 3M also work OK too, when used with a high RPM pneumatic die grinder or angle grinder.

[bbig119]

I dropped it off at the shop(Bavarian Specialties) for those who are in the Philly area. I await a phone call with quote/recommended work in addition to clutch.

It seems the rear engine seal is a bit of a weak point on these cars, it worth at least ~$100 to have them replace it, even if it appears fine?

[Anthony (M5 in Calgary)]

If your clutch has been slipping badly for a long time I wouldn't be surprised if the flywheel was damaged - heat checked/grooved. Good luck.

[bbig119]

Its been a couple weeks since I noticed it first, but it progressed rapidly. So yeah, I'm worried about needing a new flywheel. This $1000 job quickly becomes something closer to $1800.

UPDATE:

The flywheel is toast, so the quote is on the high end. For the clutch job and the flywheel, which includes labor in getting the exhaust off and replacing a few studs and hangers that broke in the process it'll cost $1933.00. They said they'd try to take a little more off if it goes back together smoothly, which made me wonder if they charge actual labor or book rate. Whatever the case, its a tough one to eat, but necessary. The shop told me that the list price on the flywheel is $850ish, but he'd knock it down to $725. That still seems a little high though. I'm not sure if I should have tried to haggle the price more, but I told them to do the work-- I'll have the car back by the weekend(tomorrow if I can get out to pick it up).

[Dave M]

Sorry to hear about the flywheel, but now you'll be good for another 200k ;)

My only question about the cost is: $100 to replace the rear main seal? Must be a real B!atch on the M60. I don't remember the seal costing too much and it didn't take too long to do on my M50, just need a drift or reasonable facsimile.

Hope you back it back soon, and cheaper than you expected.

Dave M

[bbig119]

Got the car back, after $1937 bill. $1300 in parts, $500 in labor.

It feels 100% different when I drive, the clutch takes up much sooner than it used to and it just feels smoother.

Bill is still hard to swallow, but atleast its better than it was before the clutch ever started slipping.