So I replaced my M roadster clutch line today

[BimmerBreaker]

Doesn't Rogue Engineering know the minimum number of flare is 2?

[mreloc]

Doesn't Rogue Engineering know the minimum number of flare is 2?

rofl

[BenFenner]

[Z-Thrizzle]

Ok, so here is a synthesis of the various posts and conversations on how to do this job
....

• Bavarian Autosport part No. CBT Tool (optional for compressing the slave plunger during on-car bleeding)

.....

FYI,
I have the bavauto tool if anyone wants to borrow it.

[afb]

FYI,
I have the bavauto tool if anyone wants to borrow it.

Where in NYC/LI are you?

[TurboBimmer]

Interesting. Double flare on the OEM piece (as expected) but only a single flare on the Roque piece. =(

It's hard to see if the RE is single or double flare, but the OEM seems to be bubble flare.

[Randy Forbes]

You guys jinxed me!!

I've had slave cylinders out a hundred times (probably well over >100 times) and have even deliberately been rough taking them out (when I knew I was already pulling the trans) to see if the rod would fall out. NEVER HAPPENED!

Until yesterday...

So CMM3 provides me with a slave cylinder, reputed to be from an 850i, to install with his Tilton 2-disc 7-1/4" clutch. I should've known something was up, when I inserted the slave, and DIDN'T have to compress it against the clutch arm. Missed that warning shot across the bow...

With the car just a few feet in the air, I reached in with my hand to push on the clutch pedal, when I heard PHHHTTTT TINK!! I knew what that meant...

Miraculously, I stuck a magnet in, and immediately retrieved the slave piston retainer (I thought this piece would be the hardest to snag) but I called it quits last night before I got the rod out__though I did "see it" with my video-scope, my arms gave out from working over my head before I could snag it with the magnetic tip attached (cuts visibility, so didn't have it on during the exploratory steps).

Fingers crossed...

Update:

All's well that ends well, I guess. Looks like I "missed" the fork (fok!) lever when I put the slave in. Poop (not the exact words used at the time...)!

Neighborhood's going to get a little louder once the starter and c/f airbox are back on

So the takeaway is: make sure the rod bottoms its little ass out in the fork lever, and if you lose the rod in the bellhousing, maybe you can fish it out through the starter opening__that might only work with a 7-1/4" clutch (I have NO intention of ever trying again)...

[z3forlife]

Doesn't Rogue Engineering know the minimum number of flare is 2?

Lol. Best reference ever. Don't have a case of the Mondays

[Z3MROADY]

Does anyone happen to know the dimension between the bolt holes for the clutch bleed tool? THX!

[Mr Bingley]

Does anyone happen to know the dimension between the bolt holes for the clutch bleed tool? THX!

It doesn't have to be exact--basically the same dimension as between the bolt holes on the slave--I eyeballed it.

[Tib]

60mm center to center
8.8mm holes

[Z3MROADY]

Thanks Tib!

[Tib]

Your welcome.

[Z3MROADY]

It doesn't have to be exact--basically the same dimension as between the bolt holes on the slave--I eyeballed it.

Understood. Thanks, but I'm at work and Z is at home. Had a little free shop time so I thought I'd whip one up after work. So, couldn't eyeball it don'tcha know .

[mcheeb]

So by replacing the stock line with the UUC line, does this eliminate the dreaded CDV valve? I want to tackle this job myself and it seems the risky part is removing the slave cylinder, is this necessary?

[afb]

i'm sure it's possible, but it'll be easier to bleed when removed. i just did mine w/ an RE line. bench bled it. knowing there were no bubbles in the slave/line, and the only air in the system would be up toward the master end where i reattached, i simply pumped the slave rapidly in, and slowly let it out a bunch. never touched the bleed nipple. seems to be working fine for now.

removing the slave is fairly easy. just get a 3-piece wobble extension set.

[sjdennis]

Just changed mine last Saturday. UUC line on my S54 M. Thanks for this great DIY.!

I did have a fearful moment when the golf tee broke off in the solid line from the master. Aargh !!
luckily my son just pressed the clutch and the piece popped out... Made a bigger mess than I hoped for. The brake fluid is really slippery with nitrite gloves on. Paused the whole job to clean up and get fresh gloves.

Pulling the slave and bench bleeding seemed the way to go. Putting the slave back in took some fiddling to get it positioned correctly on the studs, then pushing it in to get the bottom nut started. You cannot see the top stud so I used some plumbers putty to hold the nut in the socket at the end of the swivel and get it started by feel. Did have to bleed the feeder line since I lost a lot of fluid with the golf tee mishap. Rubber vacuum cap may have been better.

Definitely helps to have a helper to get the line nuts off and on with a swivel head line wrench and crows foot. The clutch works much better and I don't need to mash it to the floor to get it to disengage anymore!

Well worth the effort and about 3 hours on a Saturday.

Dennis

[Mr Bingley]

Just changed mine last Saturday. UUC line on my S54 M. Thanks for this great DIY.!

I did have a fearful moment when the golf tee broke off in the solid line from the master. Aargh !!
luckily my son just pressed the clutch and the piece popped out... Made a bigger mess than I hoped for. The brake fluid is really slippery with nitrite gloves on. Paused the whole job to clean up and get fresh gloves.

Pulling the slave and bench bleeding seemed the way to go. Putting the slave back in took some fiddling to get it positioned correctly on the studs, then pushing it in to get the bottom nut started. You cannot see the top stud so I used some plumbers putty to hold the nut in the socket at the end of the swivel and get it started by feel. Did have to bleed the feeder line since I lost a lot of fluid with the golf tee mishap. Rubber vacuum cap may have been better.

Definitely helps to have a helper to get the line nuts off and on with a swivel head line wrench and crows foot. The clutch works much better and I don't need to mash it to the floor to get it to disengage anymore!

Well worth the effort and about 3 hours on a Saturday.

Dennis

Glad you found this thread useful. The new hose makes a huge difference doesn't it.

[Rob Levinson]

Glad you got it worked out. Every now and then, a BMW hydraulic system can be a pain to bleed properly. It's happened to me too.

[bzsm]

Love the attitude!

[weenerdog]

Ok, I just replaced my line because the clutch stop had been removed by the PO and it was still hard to get into first at a light. Just finished up, power flushed the whole system at 10 psi (water was at 2%, so it needed it). Just tried it out. No change. Feels exactly the same as before. I had the slave out and upright during the flush and it was rushing through it for quite a while; don't see how any air could be in there.

So, what does that mean? Clutch almost gone? Clutch master? Clutch slave? I had high hopes for this one...

[rf900rkw]

If the bleed port is not at the top during bleeding, you will not get the air out. This is not the same as having the bleed screw at the top, it must be where the port intesects the bore. If it isn't done right, it doesn't matter how much pressure, how long, or how much fluid you waste through the system, you will not get the air out.

[weenerdog]

The bleed screw was up, but it was hand-held (for several minutes) and the orientation was manipulated, wiggled the piston, etc. Hard to imagine there's still air in there, but it would explain the situation...

[Mr Bingley]

Kinda sounds like there's still some air in the slave. Go back to post 55 and re-read the various bleeding procedures. The general consensus is that power bleeding will not cut the mustard on this one.

[TurboBimmer]

Could it be a misadjusted clutch pedal?