2005 Cooper S, 63K mi, white over BRG. I have had problems with the slave cylinder failing twice. The first one failed at about 30K mi and the second one failed at 61K mi. Shortly thereafter (63K mi) the hose separated from the slave cylinder and of course the system lost pressure and the clutch failed again. My mechanic, who is very good, said that he is appalled at how underdesigned the slave cylinder (plastic) and the slave cylinder/hose connection (plastic hose w/clamp, rather than threaded fitting) are. He says that when the clutch is depressed, the slave cylinder and the slave cylinder/hose connection flex visibly. BMW makes a special tool with which to bleed air out of the system, and it is difficult to do, even with the tool. On this last repair, he used a high temp adhesive, in conjunction with the clamp, to enhance the connection, but says that this is only a temporary solution, and that he doesn't recommend driving the car out of town. I am not hard on the clutch. I drive the car vigorously, but never dump the clutch from a stop, and never take the car to the track. I have not found any aftermarket parts manufacturer which makes a stronger slave cylinder or better hoses. I also have not found others who have had this same problem. I routinely drive in remote areas, where i am unable to get the car serviced, and had the car towed over 100 mi after this last failure. Anyone know how i can solve this problem and get back to having some fun out in the sticks?

 

Sorry for your problems I have a very heavy modded 05 MCs with 52K on it without any issues at all.

 

Sorry you are having bad luck, but I've had no problems, and have only heard of a few failing. I did read on another thread how a guy used (I think) a S-10 slave, and made a hose. (just did a search and saw you replied to it) The slaves are not perfect, but seem to be reasonably good. MANY PEOPLE use them for racing, etc.
Is you slaves failing internally...from contaminated fluid scouring the walls and then loosing pressure? If so, NO new cylinder will ever fix the problem until the lines are fully flushed, and are clean. If the hoses are coming off them, etc....it sounds like the guy who did the install trying cop out of doing a poor job.
Adding glue to a HYDROLIC LINE is nuts.....I'm sure it worked like lube under pressure, and shot the line off!! Brake fluid is a great solvent...and it will remove paint, and i'm pretty sure even hi-temp glue!! Anybody that would admit to trying this stunt on my car would be looking for a new customer....it sounds like he needs to redo his certifications IMO. Just does not sound like a pro...more like a shade-tree guy that might be working beyond his comfort zone.

 

I'm with the others here. I still use the factory slave on the race car along with that factory fitting. I've never heard of a fitting failure. Just hear about a leaking seal every so often on the earlier cars.
Yes, they are a BIG pain to blead if doing it by the book.

I'd suspect your mechanic myself.

 

I am with onalsed.

AS someone who has completely and royally f'ed up my own slave cynlinder install, i have seen the light. This is an VERY easy task to do once you know the proper way of doing it. For starters, replace the line. It is less than $15 from the dealer and is easier to replace then a lot of other things on the mini. Also be SURE the rubber is atleast flush with the end of the metal line. If it sticks out further than the metal line, then you dont have the rubber completely seated on the plastic clip portion.

The tool makes things easy, and combined with a Motive pressure bleeder is the only true way of bleeding the system. I was having issues simuliar to yours, and after a certain awesome guy (k-huevo) came to my rescue, i have had zero issues from my slave since then.

I to was to the point you are of sourcing another slave that would have threaded lines, but now that things are the way they are suppose to be, there really is no need.

After all the issues i have had, i can now swap a slave in less then 20min from start to finish. Very VERY easy process, but next to impossible w/o the tool or a way of compressing the cylinder. Good luck you.

 

Another "BTDT" with the slave... Not hard to do, but VERY easy to do wrong, with fatal [to the slave] results. One comment I didn't know is if using a pressure bleeder, but sure not to use a lot of pressure... about 12 psi max. No, I'm not sure why it makes a difference, but apparently it does...

 

i too had a massive headache with the slave cylinder in my car as well. it was always the biggest pain during my motor pulls since i kept getting air bubbles in my master somehow.i did not have, nor had access to, a pressure bleeder that would fit the cap at the top.i finally tried reverse bleeding it when the slave was compressed by using an old-school manual oil pump. and it worked perfect! i just pumped fluid into the system from the slave and sucked the extra out the top as it filled.every time i did it i actually saw the big air bubbles that were causing my problems. it's essentially the same as pressure bleeding from the top, but i just didn't have the right tools, and now don't need them if i do it again and could do it in 15 mins if needed to as well.

 

By the way... you don't need the fancy MINI slave compression tool. Just use a few feet of duct tape to hold the piston in a fully-compressed state and swap it for the old slave. Run a pressure bleeder for a bit, then seal the system, untape the slave and bolt it in place. It works like a charm!

 

LOL honestly never thought of using duct tape. It truly is the miracle tool!

I made my own make shift tool originally with a chunk of wood and some long screws, did the trick, but the BMW tool is much more nice!

 

And if anyone has thoughts on making that a better article, I would love to hear them!

 

Put it somewhere that you don't have to register and login to view it.

- Mark

 

While the slave cylinder does crap out every once in a while, it's usually during a transmission removal and not out of the blue. The design is otherwise OK, like everyone else has said. Sorry to hear of your troubles but it sounds like you've had a spade of bad luck!

 

I'm on slave #4 right now in 4 years and 48k miles on my '06 MCS. I know 3-4 people on my local MINI board who have had the slave replaced on their '05-'06 and I sold the spare that I carry in the boot at all times at MOTD last year (at cost, for a fellow Motorist) to someone who had a slave die while there.

I know that I am obviously unlucky in this regard, but if there were an aftermarket replacement for this part, I'd be all over it.

 

I've had some issues with ours as we've gone through a few. Seems every time I turn around it's leaking. One of our guys thinks a Chevy S10 unit will bolt right in and it's all metal. We're yet to try it. It's on the list of things to do.