When bleeding/replacing brake fluid on an R56, is it necessary to bleed the clutch slave, too? I've seen how-tos for bleeding brakes on 1st gen. Minis that say to bleed the clutch when you bleed the brakes because they share the master cylinder. Then I saw in an R56 brake bleeding thread (hi, Ryephile) _never_ to bleed the clutch unless you also replace the slave cylinder, but no reason was given. Thanks in advance.
No it is not necessary -- (perhaps Keith or toddtce will jump in for us and explain the technical details). After making a pretty good pressure bleed tool I learned "toddtce's" gravity method and it is so simple, I now prefer the gravity method. Here is how "toddtce" explains it: An alternative to all this hassle is a simple, but highly effective, gravity bleed: Open bleeder nipple, let drain into bucket, continue to fill reservoir as fluid is displaced, note color change, close bleeder, rinse with WATER, done. One caliper or one end of the car at a time doesn't matter. But you'll need two buckets... Of course the big downside to this method is you must pay attention and absolutely keep you master cylinder fluid level up --- ie do not start talking on the phone and forget you should be watching and maintaining the fluid level in the master cylinder.
Still like my pressure bleeder better......... And the procedure is the same as the R53, no need to worry about the clutch slave.
Hey Brian, Yes! I now use a Motive power bleeder, but I need about 4x more time than you do. So I take it you don't bleed your clutch slave? Does the clutch share the master with the brake system on an R56? And thanks Ron and Scott(inBend). Kim
Correct, I don't bleed the clutch slave and it does share the same fluid/reservoir as the brakes. I am not sure why someone said to never bleed the clutch slave. I don't do it because I am lazy and it is not necessary.
I was hoping one of the tech gurus would step in and answer this question with authority, but in there absence I am going to say it is as simple as gravity -- ie you do not need to bleed it, as long as the common master cylinder fluid level is always above the level of the outputs. So if you don't run the master cylinder dry you do not need to bleed it and the clutch cylinder is not subject to the heat that brakes are exposed. As far as what method to use -- power bleeder -- two man -- gravity They all work very well and all have pros and cons.
I use the Motive bleeder as well on my R53, and do not bleed the clutch slave. Back on the Motive, an alternative method I use, and I know Brian does as well.....Is to use the Motive bleeder as a source of air pressure, meaning do not put brake fluid in the tank. You will have to check the reservoir fluid level after each corner bled, but you will also use much much less fluid and get to skip and painful tank cleaning when done.
I tried to bleed the clutch slave on my R53 and ended up buying myself a new one. It's a pain in the butt to do - you have to somehow keep the slave compressed while you bleed it - and it's easy to break the plastic parts on the slave. I wouldn't advocate doing it unless you have to. The clutch and brakes share the same fluid reservoir, but there's a baffle that keeps the fluids separate. For example, if your clutch line is cut, it won't drain the brakes, too. The clutch fluid doesn't get hot and doesn't need to be flushed, because small amount of water absorbed by the fluid risks no chance of boiling.
Tank cleaning? :lol: Not in my garage... pour the little bit of remaining fluid back into the can... put the top on the tank... put the tank in the box... ready for next time...
Ron, I should mention that when I asked Keith, he suggested I start this thread. Thanks for the info, everybody.
The best trick to using a pressure bleeder is to "burp" the air out of the brake reservoir and fill tube after pumping up the tank. This will cause the fluid to fill up the fill tube and eliminates a lot of the air from the procedure.
I bleed my clutch when I bleed my brakes. I figure, why not. The only caveat I have read about is if you have to not depress the clutch pedal while bleeding all the way down as it will screw up some membrane in the slave. I hope I didn't screw up that explanation.
I also bleed the clutch slave during a system flush [ame=http://www.lonestarminiclub.com/forums/showthread.php?t=476]Brake Fluid Flush - Lone Star Mini Club Forums[/ame], but this is about the R56, I don't see why the later model would be any different, contaminated fluid should be replaced or risk tainting the rest of the system. Where or what is the caveat for the R56 slave?
I don't have one. As you pointed out mine are both Gen 1 cars. But I would say it should still apply to Gen 2. The innards of the slave can't be that much different.
It seems relevant that there is bleeding for the purpose of getting the air/gas out of there and then there is bleeding for the purpose of replacing dog-hair-contaminated brake fluid with fresh new fluid (never happened to me, btw). It is important to bleed the clutch slave if you're bleeding for the second purpose, but not for the first purpose?
How frequently should brakes be bled? I know DOT fluid is hygroscopic (water loving) and I live in a pretty damp part of the world. My dealer is recommending every 2 years. Is that about right?
I don't think your geographical location makes much of a difference. It is a sealed system. Of bigger importance is your driving style and whether you track or not. If you track you should change it more often. As a rule of thumb I flush once a year, or every 10 k miles.
No track time for me, and I think I'm pretty easy on the brakes. I would have thought that geography plays a role. The moisture level in AZ vs BC would be quite different. Even though its a sealed system moister somehow gets absorbed. I know with my downhill mountain bikes after a winter the calipers are siezed and they're in need of a bleed. The hydrolic brakes however that use mineral oil don't take in water at all and are much better. The problem with those however is less heat tollerant and on DH bikes and a hard day at the bike park, thats a problem. I've just done 4500 miles after 16 months so I figure I'll wait til the 2 year anniversary and by then it'll be about 7000 miles.
My understanding is that the moisture in the car brake lines gets there not through absorption, but through release. I.E. Brake fluid heats up under braking, creating gas which turns into moisture which does not get absorbed back by the brake fluid. If I am wrong, some one can correct me.