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View Full Version : Is this a worn clutch or a bad clutch/slave cylinder?


tungsten2k
01-22-2012, 10:28 PM
My gf bought a 97' ti and after driving it, I told her it had a worn but drivable clutch (clutch didn't grab until the very top of the travel). The transmission felt a bit notchy but nothing crazy. Well she has been limping along on it for about 8mos now and has (finally!) bought the parts for the clutch.

I drove it the other day and it seemed *way* notchy-er than I remember, and even once nearly tried to pop back out of 2nd gear on me when I didn't forcefully "set" it into 2nd gear with authority.

MY QUESTION: could the clutch be so worn that it has overcome the travel capabilities of the master/slave cylinder, or do I likely have a different problem (like bad master/slave cylinder) ?

The clutch doesn't slip at all except if I try to do a drag race style start, and even then, it eventually grabs. It's hard to beleive the clutch is solely responsible for the symptoms I'm seeing. This car has 70k mi on it.

We have her old 318ti (M-Sport) with 205k mi on it that we are swapping the limited slip diff with before selling, but now I'm worried that maybe I should swap the tranny too ? All the gears feel very notching shifting, which has surely been beating up the synchros the entire 8 months she's been driving it like this.

I'd hate to do the clutch, only to find I need to take the whole thing apart again to swap the trannys :eek:

I'm welcome to any opinions ! - thanks !

tungsten2k
03-11-2012, 09:53 PM
Well, I found the problem !

For the benefit of anyone else who stumbles onto the same symptoms, there's one unlikely root cause you probably hadn't thought of: a broken clutch lever pivot fulcrum. No wonder I couldn't wrap my head around any reasonable cause for the behavior I was seeing !

The plastic pivot point slides into a cylindrical hole in the transmission to locate the other side of the clutch lever arm, opposite the slave cylinder. This plastic piece (likely glass reinforced ABS) appears to have been defective from the factory; the tip looks like it wasn't given enough time under pressure to allow all the air to be expelled from the mold, or the plastic wasn't hot enough. Either way, the the weakened hollow tip had broken off during service, resulting in a full 10mm drop in height from the new part (see pictures).

The sad part is I had never thought the synchros were being tortured the entire time we had been driving it. A working hydraulically-actuated clutch slips long before clutch disengagement is not possible, so it never really occurred to me my gf might be slowly killing the tranny.

Needless to say I'm less than hopeful that the synchros are still top notch, which sucks because this car has only 70k. I've decided to gamble and install it anyway, in hopes the synchros are still good, and if not will pull it all apart again, along with my other 318ti with 210k that I'm planing to sell after all this. I've got my fingers crossed. Wish me luck! :)

By the way, I decided to go with a Fidanza 12lb flywheel so will be putting a good dual-mass along with a new Sachs clutch kit and flywheel bolts up on the classifieds. It's pretty much everything you'll need from the crank to the transmission for a fresh flywheel/clutch job. The Fidanza uses a 240mm sprung M3 disk and pressure plate so I couldn't use the stock 215mm unsprung setup I bought from Turner :(

This is by far the most difficult clutch job I've ever done. I miss my 911 in that regard ;)

I'll update on the outcome once it's together.

spidertri
03-11-2012, 11:40 PM
If you're interested, rally road sells a stainless version of that pin. $15

http://www.rallyroad.net/content/clutch-pivot-pin

tungsten2k
03-12-2012, 03:53 AM
Thanks for the tip Dave.

That a product like that exists, begs the question of whether plastic is a good material to use for a clutch pivot point :_punch:

zoner
03-12-2012, 07:16 AM
That a product like that exists, begs the question of whether plastic is a good material to use for a clutch pivot point :)

Judging by the look of what you pulled out of there, I think you have your answer.

The rally road pin sounds like $15 well spent. :smile:

What are you looking to get for the flywheel/clutch setup and has it even been installed?

tungsten2k
03-12-2012, 08:54 AM
Judging by the look of what you pulled out of there, I think you have your answer.

The rally road pin sounds like $15 well spent. :smile:

What are you looking to get for the flywheel/clutch setup and has it even been installed?

We had around $300 Amazon credit from turning all our coins in at a Coinstar machine, so we went with a Fidanza from Amazon and will get a stock Sachs M3 clutch kit. I'm trying to see if Turner will swap our 318ti kit for the M3 but not sure how that will go since the box is opened. We could have stuck with the dual-mass but we had this credit, and besides: it just feels like such a tractor when spooling up getting on the freeway or downshifting to pass someone. Have yet to get it installed, but it sure is light and purdy: