Clutch won’t disengage - 530i5 w/ all new components

[computiNATEor]

Alright, I really need some advice. Any thoughts, experience or tips would be greatly appreciated. Here’s what’s been happening. Just to be clear, when I say the clutch is “disengaged” or “released,” I consider that to be when the clutch is not transmitting power to the rest of the drivetrain.


I recently wrapped up a major service on my 2002 530i with the ZF 320Zfive speed transmission. As part of that extensive $5000+ service, I replaced the clutch and flywheel with a UUC B1 lightweight flywheel and E34 M5 clutch disk and pressure plate assembly. The transmission input shaft seal was replaced, the throw out bearing guide tube was replaced, throw out bearing (Sachs), pivot pin (All German Auto brass from FCP) and pivot pin spring/clip thing were all replaced. I lubricated everything with small amounts of aluminum anti-seize compound, following the instructions in Bavarian Autosport’s excellent two part clutch DIY on YouTube.


I had a very difficult time bleeding the clutch hydraulics after removing the Clutch Delay Valve, but a shop took care of that for me and the car was running beautifully. I put 1300 miles on it, and it was great. There is a good bit of gear rattle, especially once the transmission is fully warmed up, but the E39 is pretty well insulated, and it is barely audible with the windows up and AC on (which is 99% of my driving).


I had some issues with 3rd gear grinding when downshifting from 4th, even when rev-matching or heel toeing as best I could. I chalked it up to worn syncros on the transmission, and/or sloppy shifting skills. This transmission is a replacement ZF 5-speed from a parted out 98 M3, according to the VIN tag. I ground up the syncros a bit on my old 5-speed learning to heel toe badly, plus it was covered in grease and oil and just disgusting. I have no clue whatsoever of the mileage on this transmission, but the old one had at least 211,488 miles on it, because that’s when I removed it.


On Wednesday, I was driving around doing some errands and the car became increasingly difficult to get into gear from a stop. Like, full- body, full- effort pushes on my E60 shift lever to get into gear at a stoplight at the end of it. Way harder than ever before. I thought at first that the transmission was getting too hot; I had been in more stop and go traffic than I had ever before with this new transmission fluid and clutch/flywheel.


Once into gear, it was fine. The engine didn’t bog or stall and the car didn’t lurch or anything like the clutch was engaged. And as soon as I got moving, it was very easy to upshift and downshift without grinding or anything.

But I quickly realized that the clutch was engaging right off the floor. I stopped to do one final errand, and when I came back to the car, it was toast. It wouldn’t go into gear at all if the engine was running. I thought it might just be a simple slave cylinder repair as it was a sudden problem, but not an immediate problem. I had the car towed to my mechanic. The issue showed up gradually; it didn’t feel like it was an all-at-once thing like a light switch. Rather the symptoms got worse and worse until the clutch no longer disengaged and the car and I were stranded. Thank god for AAA, but unfortunately I have now used all my free tows for the year, and one of my parents’.


The mechanic was a big mistake; he charged me $450 for a slave cylinder that took more than a day. Grr. This is why I DIY. Anyways.


He replaced the slave, which I believe to be original. When he removed the old slave cylinder, there were some odd wear marks on the side of the rod.



Sorry, on an iPhone right now; pictures aren’t the easiest to insert. See attachment below.



See how it’s gouged out on the left side, below the brown dirty area? And those ridges? What could cause that? The slave pin has been wearing against the side of the slave cylinder housing, so the pin is moving somewhat sideways when being actuated. It would appear that the slave pin is being forced away from the input shaft, towards the outside of the transmission, when the clutch is depressed (disengaged).


There’s no obvious leaking from the master or slave cylinder of any kind. There are some drips from the transmission; maybe my new input shaft seal isn’t sealing well. I used Redline 75w190ns plus Redline MT-90, which is UUC’s hot climate gearbox rattle suggestion.


My mechanic wanted to drop the transmission out, obviously. But I’m running an aftermarket clutch kit, and once he knew that, it was basically “you’re on your own.” Totally understandable.


So I removed the slave cylinder, and I’ve been poking around at the clutch fork. The clutch fork feels like it has some up and down free play, which probably allowed the slave cylinder to bind up against itself and probably caused the galling. The new slave cylinder my mechanic installed has some galling in the same places already, though the clutch has only been pressed a couple of times, and the car hasn’t been driven anywhere (under its own power).

[computiNATEor]

I really don’t want to pull the trans, especially because it was just out! Many of the other posts with similar issues seem to be on cars with worn components. These components are less than a month into their life!

[effduration]

Was the used ‘98 M3 transmission installed at the same time (1300 miles ago) as the rest of your major service?

[computiNATEor]

Yep

[computiNATEor]

I've been fiddling with the slave cylinder and clutch fork through the slave cylinder opening. I think either the throwout bearing failed, or the clutch pivot pin or pin spring is broken. No change after trying to reassemble everything; still won't go into gear. I've lifted the rear end up and I'll begin disassembly tomorrow. Yay...

[pleiades]

I've been fiddling with the slave cylinder and clutch fork through the slave cylinder opening. I think either the throwout bearing failed, or the clutch pivot pin or pin spring is broken. No change after trying to reassemble everything; still won't go into gear. I've lifted the rear end up and I'll begin disassembly tomorrow. Yay...

Strange.... and here I was about to suggest (over-)topping up the brake/clutch fluid reservoir just to rule that out.... Sounds like you have a long day ahead ...

[computiNATEor]

Yep, tried that. The reservoir was full when I checked it while waiting for the tow truck

[Mike WW]

Since the slave pushrod is worn, it says to me the pivot pin is an issue since it locates things on the other end. I suspect the problem will be clear once you do the unenviable task of pulling the tranny, but it might be the release lever, the pivot pin or the TO bearing.

[computiNATEor]

Since the slave pushrod is worn, it says to me the pivot pin is an issue since it locates things on the other end. I suspect the problem will be clear once you do the unenviable task of pulling the tranny, but it might be the release lever, the pivot pin or the TO bearing.

Yeah, I think you're right. Thankfully, everything was just apart, so I don't have to fight any stuck bolts.

[itsbrokeagain]

I'm going to bet the plastic pivot pin crumbled. As part of your $5000 service, it's going to be humbling that a $1 part is forcing you to take this all apart again.

[effduration]

I'm going to bet the plastic pivot pin crumbled. As part of your $5000 service, it's going to be humbling that a $1 part is forcing you to take this all apart again.

OP mentioned using a brass pivot pin as part of the recent service.

[computiNATEor]

I'm going to bet the plastic pivot pin crumbled. As part of your $5000 service, it's going to be humbling that a $1 part is forcing you to take this all apart again.

That’s why I replaced it with a $40 silicon-bronze pivot pin, with a dab of anti-seize at the tip and a brand new spring/clip for the new clutch fork, new throw out bearing, and new guide tube. Which is why I’m so annoyed.

OP mentioned using a brass pivot pin as part of the recent service.

Exactly. I went with a part sold by FCP Euro, so we’ll see what’s what when I get in there.

[pshovest]

Has the close-to-floor engagement been there ever since the clutch install or has it gotten progressively closer to the floor? The M5 pressure plate will require higher hyd pressure and may have caused the 200k mi MC to leak internally. I'd replace the MC before pulling the trans.

[computiNATEor]

Has the close-to-floor engagement been there ever since the clutch install or has it gotten progressively closer to the floor? The M5 pressure plate will require higher hyd pressure and may have caused the 200k mi MC to leak internally. I'd replace the MC before pulling the trans.

Hmm, good point. I shall replace it ASAP.

[computiNATEor]

Actually, upon further thought... Why would the slave cylinder pin be scratched up if there wasn't a mechanical problem in the bell housing?

[pshovest]

Don't know for sure, but the slave photo shows the rod fully extended. When installed and foot off the clutch only a little more than the plastic tip is exposed inside the bell housing. The scratches might be from attempting to reinstall slave with rod fully extended, struggling to compress the slave to get the nuts attached, while on your back, cussing & swearing about what a pain it is to install the slave. The more important wear is on the bottom of the rod where the diameter is reduced. This is wear from the bushing that supports the rod at the end of the slave. This certainly looks like a 200k slave.

[pleiades]

"I lubricated everything with small amounts of aluminum anti-seize compound...."

I was wondering about this, recalling how BMW TIS said go easy on lubing the guide tube. Is that anti-seize you used rated for this kind of application (hot with lots of friction-disc dust)? I'm trying to picture the scenario where the TO bearing gets sticky....

[computiNATEor]

Don't know for sure, but the slave photo shows the rod fully extended. When installed and foot off the clutch only a little more than the plastic tip is exposed inside the bell housing. The scratches might be from attempting to reinstall slave with rod fully extended, struggling to compress the slave to get the nuts attached, while on your back, cussing & swearing about what a pain it is to install the slave. The more important wear is on the bottom of the rod where the diameter is reduced. This is wear from the bushing that supports the rod at the end of the slave. This certainly looks like a 200k slave.

Oh, no doubt it’s old. However, I don’t remember the slave having those wear marks before I changed the clutch. I think I would have noticed that. That’s a LOT of wear to happen in 1300 miles.

Side note: why does my iPad keep autocorrecting miles to Miles? It’s really annoying.

"I lubricated everything with small amounts of aluminum anti-seize compound...."

I was wondering about this, recalling how BMW TIS said go easy on lubing the guide tube. Is that anti-seize you used rated for this kind of application (hot with lots of friction-disc dust)? I'm trying to picture the scenario where the TO bearing gets sticky....

The Permatex aluminum is rated for 1600°F.

https://www.permatex.com/products/lu...e-lubricant-2/

[geargrinder]

Huh. The orig description sounds like classic failed slave and/or clutch bleed - BTDT, slowly getting harder and harder to get in gear but tranny working fine otherwise... But clearly its more than that. The arm pivot pin doesn't really do much of isth if all is well. I thought about the blingy brass ones myself but coudln't really make an argument for it, its a rare failure although at 211k yeah I'd have put a new plastic one it at least. The arm spring doesn't really do anything except hold it in place until the whole damn thing is assembled... can't see that being an issue if it was working alright. I'm probably on the throw-out bandwagon at this point? Although if it was a seized/sticking throw-out, then, it should shift great or at least fine while stationary / engine off, and, typically that makes some kinda awful noise if its borked up.

You're sure about the clutch parts fitment etc? Stack height etc. etc. all compatible?

Re: Side Note: Random capitalizing of random nouns in iOS is a massive annoyance that came out a few versions ago when they clearly overhauled the autocorrect engine. A 'house' is always now "you must mean 'House' the TV show!" A 'crane' is always "You must mean a person with the surname 'Crane'!" etc. etc. etc. There'z innernet complaints about it, you are in good company.

[computiNATEor]

Yeah, it shifts totally fine with the engine off. Like butter.

[computiNATEor]

Huh. The orig description sounds like classic failed slave and/or clutch bleed - BTDT, slowly getting harder and harder to get in gear but tranny working fine otherwise... But clearly its more than that. The arm pivot pin doesn't really do much of isth if all is well. I thought about the blingy brass ones myself but coudln't really make an argument for it, its a rare failure although at 211k yeah I'd have put a new plastic one it at least. The arm spring doesn't really do anything except hold it in place until the whole damn thing is assembled... can't see that being an issue if it was working alright. I'm probably on the throw-out bandwagon at this point? Although if it was a seized/sticking throw-out, then, it should shift great or at least fine while stationary / engine off, and, typically that makes some kinda awful noise if its borked up.

You're sure about the clutch parts fitment etc? Stack height etc. etc. all compatible?

Re: Side Note: Random capitalizing of random nouns in iOS is a massive annoyance that came out a few versions ago when they clearly overhauled the autocorrect engine. A 'house' is always now "you must mean 'House' the TV show!" A 'crane' is always "You must mean a person with the surname 'Crane'!" etc. etc. etc. There'z innernet complaints about it, you are in good company.

Yeah, no terrible noises. It just won't go into gear. It will if the car is in the air, though, and there's no load on the rear wheels; the wheels spin with the engine.

I'm pretty sure the UUC B1 lightweight flywheel and E34 M5 clutch is a proven combination. It's been used for decades amongst the E36 guys; anyone with a ZF S5D 320Z transmission, really. There are dozens of reviews online, and maybe tens of thousands of kits sold. No one has ever mentioned needing spacers or adjustable clutch slave pins on any of the guides I've seen.

- - - Updated - - -

Re: Re: Side Note. Yeah, I think they incorporated some "machine learning" (Apple's favorite word as of late) into the new algorithm. It's so annoying.

- - - Updated - - -

So say I pulled the transmission out in about 4-5 hours this morning, and there's only one obvious point of failure, but that failure could have occurred while pulling the trans?

The pilot bearing is loose in the back of the crankshaft. But it's very possible that I unseated it while removing the transmission.

Nothing else looks obviously out of place.

[computiNATEor]

Here's the bell housing area. Note the bronze dust by the pivot pin. I removed the clip to look at everything, then reassembled it for the photo. The spring clip/pin were in fine shape.
IMG_0005.jpg

Close up of bronze dust.
IMG_0673.jpg

Throwout bearing looks to be in good condition. The "face" where it touches the clutch spines seems to be in fine shape; maybe a bit of wear from forcing it into gear that last day, but otherwise ok. The bearing rotates smoothly and without binding, but not too freely.
IMG_9973.jpg
IMG_7909.jpg
IMG_7089.jpg

[computiNATEor]

Where the old and new slaves pushed on the new clutch fork:
IMG_4987.jpg

Where the pivot pin was, with some of the anti-seize wiped away:
IMG_3621.jpg

Pivot pin in place, with anti-seize. That does look like a fair bit of wear, TBH.
IMG_3591.jpg

The input shaft seal is obviously leaking, even though it's new. I'll address that while I'm in there.
IMG_1538.jpg

New throwout bearing guide tube. It has some wear, but I don't see anything spectacularly wrong here. When felt by hand, there's only smoother spots where the TOB has been sitting, but there's no missing material. I could maybe add some more anti-seize before it goes back together.

I do see metal shavings here. Maybe that was from the throwout bearing coming into contact with the clutch fingers? Any ideas?
IMG_8282.jpg

[computiNATEor]

Pressure plate fingers. That looks like a fair big of wear for 1300 miles, but a day driving around with a not-disengaging clutch probably didn't help that. The stickers are still on it (hidden by my crappy camera angle).
IMG_2922.jpg

The input shaft looks like it was riding in the pilot bearing just fine, which makes me think I just dislodged the pilot bearing when I removed the trans. There's no grooves in the input shaft that I can feel; just lines of grime.
IMG_3894.jpg

[geargrinder]

Huh. Is the TOB the right one? The wear marks on the TOB itself look perfect (concentric, center of the face) but the PP fingers do look worn vs the mileage...