First I apologize if there is already a thread on this but I did search and I've been working on the car all day and need some quick wisdom.

Today I installed a set of used JCW big breaks one the front of my 03 r53. I bought them in the marketplace. While at it I decided to install some steel brake lines and rear brake bushings from Way.

I didn't get to the rear steel lines because I couldn't get the old line loose. Installed everything less and bleed the fresh fluid.

Here is the issue - pedal is VERY soft and basically goes to the floor with no stopping power. If I pump them at least 3 times I do get a firm pedal and the ability to stop. Any ideas? Did I mess up the bleed?
Was going to rebleed the system but now the back right bleed valve is just about stripped.

Thoughts?

 

Yes you need to rebleed it. You most likely still have air in the lines.

 

Check this out
http://www.pelicanparts.com/techarti...ing_Brakes.htm

 

Definitely need to re-bleed. Did you use a power bleeder, mightyvac, or someone pushing the pedal? Easy enough to get replacement bleed valves, and make sure you use the correct size wrench and be *gentle* with them. They don't need much torque.

 

Thanks guys. I actually tried 2 options (with and without a helper) but think ill try and pick up a pressure bleeder today for my next attempt.
I'm a bit worried about the one valve though. It was very tight (must be a bit rusty) the first time and then it almost completed rounded the second time. I have to figure out a way to get it loose or ill be buying a new caliper.

Bram - thanks from the pelican link. I was actually reviewing that last night. I find they did a great job with their DIY projects. Greats pics too.

 

Did the reservoir ever get empty during the bleed? I'd try bleeding again first with the pressure bleeder, but if that doesn't work, there may be air in the ABS.

 

Figure out the stupid valve so trying another bleed now. If its the abs, anything I can do to resolve it?

 

Activate the abs....so stomp on the brakes....a stretch of pavement with lots of sand/gravel is good. A pro tool can do it...but kinda $$$$.

 

There is only one way to get it out of the ABS, and that's with a tool. The dealership can do it, but it's not cheap, although it's not bad. No amount of bleeding/stomping etc. will get it out if it's in the ABS. However, if it's just air in the lines, and hopefully that's all it it is, a good rebleed will fix it.

 

Thanks again. Bleed it two more times and still issues. Ran through parking lot locking them up for bit bit and will rebleed tonight. If that doesn't work ill be at the dealer this week.
Going up mt Washington this weekend so I have to get them sorted.

 

Buy a good 6 point box wrench or even a tubing wrench. That will help to keep from rounding the bleeder. I have, at times, used a MAP gas torch to heat the caliper to loosen a rusted bleeder and, no, the seals were not destroyed. Pressure bleeder may help if the problem is outside of the ABS. For the future, I made small, tapered silicon rubber plugs to go into the line when I disconnect it to keep from draining all of the fluid. The other options that I have used is to plan the change out really well and make sure that you can undo the final connection so the hookup goes quickly that way you won't loose too much fluid and remember to keep refilling the reservoir. Just did a set of Wilwoods using that method and was successful.

Hope it goes well.

 

Did you "bench bleed" your new calipers?

Another thing is one time I had a car that just wouldn't seem to bleed well. In the end I removed the caliper from rotor, put a piece of wood between the pads, and held the caliper as high in elevation as the brake line would allow. That did the trick in that instance.

Edit: I didn't say: if nothing else works, and you try bleeding from an elevated position like that, make sure you hold the caliper in such a way that the bleed valve is on top. Tap lightly on the side of the caliper with the handle of a screwdriver... Not sure if this tapping actually does anything, but I do it anyway.

 

When I've changed my brakes/lines a month or so ago, I've used the Motive bleeder, works great. If you are bleeding by hand, at least use a bottle with a tube and some fluid in it (to see the bubbles coming out and won't allow air to get back it).

 

I learned this the hard way. You will need to use either software like autoinginuity or BMW GT1 to turn the ABS into "bleed mode" to get the air out.

Sent from my iPad using NAMotoring

 

What ?

You don't bench bleed calipers... Only a master cylinder.

The screwdriver serves to shock sticky air bubbles off the internal iron/aluminum surfaces on the caliper...

OP.. It does sound like there is air trapped...

If you did let the M/C run dry.. You have air trapped inside the cups... That is where your problem lies.. You need to:

1 - fill M/C with fluid.

2 - have helper press and hold the brakes.

3 - while brakes are held, one crack line loose on the M/C. Close it once the air spits out. Do this several times.. Then move onto the next line..

That or remove the M/C and bench bleed it.

 

Oh, we'll I dunno what you call it. What I did last time I rebuild a caliper -but it wasn't a MINI, so maybe it doesn't apply (though I can't see why not, it's hydraulic)

I had filled the caliper with brake fluid, put in the new piston seal, and inserted the piston. Brake fluid was coming out both of the other two holes as I pushed the piston back into place. Installed the bleed valve, took it over to the car, attached it to the brake line, cleaned it up, and installed the pads.

I dunno what to all it, I thought it was called bench bleeding, but when you put a new caliper on a car, don't you "do something" to fill it with brake fluid before you install it?

Edit: I hope I didn't get too far off topic here. IF the master cylinder ran dry, then ya Do what danjreed says to expel the air. Since OP installed new calipers, I suspected a big air pocket may have been caught in there. Used to always need to get the caliper up above the fender to get all the air out, till I found a better way to fill the caliper before putting it on the car. Had a couple of them, and parts cars, so I moved and refurbished bits and pieces from car to car a lot as two of them were daily drivers at different times. -Then again I need to stop comparing new MINI's to old Fiats. They're both quirky but each in their own way.

Also, I'm curious to know how you like your JCW brakes after you get it worked out. Are they R53 JCW (like r56 S), or the really big brake kit from a new JCW?

Best Regards
AlexQS

 

That was my guess, the reservoir got low enough to get full of air in it which caused it hard to bleed.

 

Ah, I see. Just as an FYI, you don't need to "fill" the caliper.. just dip the seals in brake fluid.. Calipers go on the car dry... with the exception of installing fresh seals or pistons.. I wipe a little fresh fluid on the piston where the seal sits as well.. but no need to flood it. I'm sure the only thing that happened was a little mess.

Sorry top drag this OT.

 

Enzo- Have you resolved this issue? It is possible as others have stated that air was introduced into the ABS module. Another issue may be that air is entering a line connection that may not be completely tight.

Let us know what the outcome is.

 

Spent the day at a skip barber racing class (happy Father's Day to me!) so haven't had a chance at another bleed, BUT, something hit me this am while I was reading your article. I think I may have installed the calipers on the wrong sides. They weren't marked but have writing on them so I installed them so the writing was right side up. This put the bleeder valve on the bottom. I thought about it while I was doing it but figured i was correct because of the writing. After seeing some pics on google I think the bleeder should be on top. Makes a lot of sense and should have been obvious to me while installing but it was late and I rushed. Please tell me I'm right and that swapping the calipers should do the trick.

Side note - pelican, thanks for all your great articles. They are some of the best around!

 

Bleeds go ON TOP!


Btw, sweet gift!

 

Bleeders definitely on top. You can fight the law, but not the law of gravity!

 

Congrats on the father's day gift.

And glad you found the problem. Let us know how the swap goes. You should figure out a way to plug the lines the lines so you can get the calipers from one side of the car to the other without draining the reservoir.

 

Victory!!!!

Swapped and bled and working perfect! These JCW brakes and the new bushings for the rears sure give me much more bite. Thanks for all the help and advice. Lesson learned here for sure. This is why this is my hobby and not my profession.

 

Glad it was an easy fix!