Hi all: any help/repair of caliper dust boot replacement would be greatly appreciated!

Specifically: I just got back from two fun filled days at New Hampshire International Speedway driver's school, and my 2005 Cooper S performed fantastically. I put in performance friction 97 race pads and motul fluid and the car stopped well, no fad or brake performance problems.

However, when I put back the stock pads, I noticed a small tear in the front brake pad caliper dust boot, as well as the rear passenger dust boot looking a bit frayed, but no tear yet. I now want to replace these boots, and ordered a caliper repair kit front and back from Classic MINI.

Can I just carefully pull off the old boot, and carefully put on the new boots I receive in the kit? I plan to do this with the caliper on the car, not wanting to detach the brake line. Is there a special technique for this?

I prefer just to repair it myself, instead of taking off a day from work, driving to the dealer, and waiting. The front and rear repair kits from MINI cost $29 total, so the money isn't worth going to the dealer...

Any help????????????

Thanks, Matt

 

hello there, the caliper does need to come off, but you won't have to disconnect the brake line. I just did my brakes and replaced the rubber guides with brass ones from turnermotorsports. The rubber just pulls right out though, then push your new ones right back in. If you get interested or want to know more about the caliper stiffening kit with brass guides, do a search and read away.
take care.

 

Yes, I also did the caliper brake stiffeners, and actually just returned them to stock for the winter salt season here in new england. I was unsure if you mean that the caliper dust boot (only one per caliper--- the thingy that covers the piston) just pulls off and a new rubber boot just pushes on?? Or were you referring to the rubber guide peices that house the caliper bolts and that the guide bolts go through.. I hope its that easy

 

dude my bad. I was talking about the caliper guides.

I'm not sure if you can just pull that boot off and replace it, I think you can though. I had to tug on mine a bit to let the air out after compressing the piston back into the caliper.
Ask MINI, they should be willing to share some info on this task.

 

look at the edge where it would attach to the caliper. does it look like it has a little lip, or does it look like there are several small ridges?
if it has a lip, the piston has to be removed, the other style just presses on

{edit} oh yeah, both really require you to take the caliper off of the car, just to make them manageable.

 

thanks for the info.. I think it has lip, but I will need to look at it... I will post details if I actually do this repair.

I hate to break the line and take the caliper off the car...

anyone out there actually do this repair on an ATE caliper?? It reminds me of my e30 brakes. I think mine may have become cracked from the changing back and force between race and stock pads.. and heat of the track... or more likely possibly from the coat hanger I used to hold the caliper up during brake work damaging the boot...

I may ask the dealer to fix this under warranty, but I bet with the best circumstances, the dealer will look at the car, then agree to fix it, but not have the part, order it, and I will need to take two days off to get this fixed...

I bet this may become common as MINI's age, or should I just not worry about it

 

If you track your car this will happen alot--the heat just kills the rubber. I went as far as rounding up a spare set of front calipers for my old 318ti....haven't run into this with the Mini yet. If you have another car to use you can remove the calipers and send them out for rebuilding if you can't/don't want to do it yourself--that's what I used to do.

 

You can do it yourself, just get out your reading glasses and follow the instructions. You will need to remove the caliper, but not the lines. You're not doing any work internally on the piston seals, just replacing the dust boots.

More than likely they were damaged from heat build up during your track day. Happens to me all of the time. In fact, I won't be replacing mine this time around, but I do change the pads quite frequently during track season, so I'll be able to clean them up. I don't drive it during the winter.

 

There are tools out there that can be used to "pinch" the brake lines when changing out calipers. These allow for minimal fluid loss and also don't damage the brake lines themselves.

Please explain the " craked" statement above? I certainly hope the caliper does not have any cracks in it.

Never looked at mine, are the pistons made out of steel? If they are, boot replacement is ESSENTIAL to proper caliper operation,unless you plan to rebuild them OFTEN.

 

The crack is in the brake caliper piston dust boot cover. The brakes work great, and the rubber piston caliper boot is just cracked a 1/4 inch. The dust boot (I believe) just keeps out brake dust, water, crud, etc, and therefore protects the piston. Similar to a CV boot on a drive axle. The car only has about 7,000 miles on it, but I think the boot may have deteriorated due to the heat of race pads, and running the oval at New Hampshire, which requires heavy braking coming into turn 3.... Reminds me of cooldown lap importance... I will look at the caliper rebuild kits I am getting which have the dust boot included and try to replace without disconnecting the brake line, but will disconnect if needed (thanks for the info on the brake line tool crimper to minimize brake fluid loss). Again, anyone replace the caliper dust boots on a ATE MINI caliper front or rear chiming in would be cool. In thinking of this, I imagine many folks just don't worry about this, and evenually the piston becomes harder to retract... I just want my 2005 MINI to remain in optimal condition....

 

If the boots become damaged, they should be replaced, so you're doing the right thing.

In my case, I am speaking of my track MINI, on which I change the brake pads just about every other weekend during track season. I am in there frequently and am able to clean the piston before retracting it. On my daily driver MINI, I wouldn't think of running without the dust covers.

To clarify my earlier statement, you'll have to remove the caliper from the rotor, but not from the line.

 

thanks, that is what I wanted... to be able to remove the caliper from the rotor, and carefully work on replacing the dust boots (front and rear) without breaking the brake line, and move on with other projects on the car...

can't seem to find any instructions on the web for MINI cooper ATE brake rebuilding ... but still looking... appreciate the information....

my thought is that the ability to stop, is by far the most importance function of an automobile....

 

Hi.. just following up on this thread. I received the dust boots from Classic (quick service- thanks Jayson)... and the instructions state the caliper must come off the car (hence the brake line disconnected) and the brake caliper piston removed using compressed air (which I don't have), then reassembled with new caliper dust boot...

I may try, but seems like I may try and get the dealer to fix under warrenty since car is only 10 months old, and has 7k miles.... I can bring the dust repair kit to the dealer so they can possibly do it the day I bring the car, and avoid having to come back a second day post their ordering it...

the moral of this story is to be careful with the MINI's dust boot when changing pads, and I am still unsure why this happened, except that the heat generated from track work, along with race pads (pf97) could have compromised the dust boot.... on the other hand, the car stopped fantastic on stock brakes other than caliper stiffiners, motul fluid and pads....

Any suggestions on how this can be done by the home mechanic would be still appreciated... motor on

 

If you have someone to help you, you could try this: get car set on jacks, tire removed, caliper off the knuckle (leave the lines attached), remove the pads, and have friend pump the brakes (piston should start to come out-let it come out at least halfway from the caliper) do not let the piston pop completely out...would be VERRRRRY messy; crimp brake line and remove caliper-drain as much fluid as you can at this point. piston should be pretty easy to remove at this point (do not use any tools to grab and/or pull on the piston, just your hands), keep plenty of rags around to mop up all the brake fluid there is still going to be. If the kit doesn't have instructions on how to put the boot on and put it back into the caliper, I can type that out, too. be careful when putting the piston back in, the rubber seal in the piston bore can be damaged if you are too rough.

 

thanks Polmear... sounds challenging... I will carefully think this through prior to doing it though....

Matt

 

no problem! another thing I just thought of, if you know of anyone with a compressor, perhaps a local garage/gas station, maybe an auto parts store...just throwing out ideas...would let you use their air hose for free, or at least for cheap...you could blow the pistons out yourself.
compressed air is definitely the best/easiest way to go.

 

So does any one know how much the rear right caliper dust boot costs?

 

shouldn't be that much(I would guess about $13-20 for a kit), you'll probably have to buy both right and left boots, though.
If the rear calipers are the "lip" style boot (90% likely), this may or may not be easy, depends on how the integrated park brake is held into the caliper with the piston out. I know that our piston pops out pretty easily after it has been screwed to the end of the adjuster.

 

This happens all the time with ATE calipers on tracked cars. I have to rebuild mine on the M3 track car at least once a year, sometimes more frequently. Excess heat causes the rubber to become brittle, at which point the dust boot pulls out of the caliper's retaining groove and can't be put back. And if you try to use up as much of the pad friction material as possible - and why wouldn't we? - the extra extension of the piston pulls even more on the dust boot and makes the situation worse. Sigh.

You must remove the piston from the caliper in order to get the dust boot's lip seated in the groove. Since this is going to open the sealed brake fluid circuit anyway there's no advantage to trying to do it with the caliper on the car, which would probably call for using about 4 hands while working in the cramped and dark wheel well. The rebuild kit includes both piston seal and dust boot, so you might as well replace both while you're in there.

Because it's a messy and time consuming job you may find that your dealer will only replace, rather than rebuild, the brake calipers. Expensive, but therefore worth doing yourself. I note that Bentley doesn't cover the rebuild procedure either.

There's a knack to doing it right plus a few tricks that can help. I still have a how-to post I wrote back in 2001 for my M3; the Mini procedure is essentially the same except for the piston-twisting needed for the rear calipers. It would also be similar to your old E30. Let me know if you'd like a copy.

Neil
05 MCS
96 M3

 

I'd love a copy; as stated above I haven't gotten to the rebuild point yet but with 30 or so track days per year I'm sure I will.

TIA,
Gary
05 MC

 

I could use a copy as well. I shreaded the boot as I was changing the brakes. The piston was out just too much to get the caliper tool in so was frustated and trying to get a half inch of space and got mad. Oh well guess it will teach me to lose my temper.

 

cost like $12 i think for the rear rebuild kit and $17 for front I remember, prices I paid from classic was $35 with shipping i remember.. any instructions being send around would be greatly appreciated. Also, I asked for passenger side boots, but I don't think there is a left or right kit.

the rear on my car isn't broken yet, but looks fatigued/dried out, a bit stretched...

front has like a 1/8 inch cut in it.. Thinking of putting a tiny bit of permatex on the rip, letting it dry for 24 hours, and then putting back together, any thoughts on that.............
with goal of getting me another 3k to 10 k dealer service...

I bet the dealer might change front caliper once, and not repair. I will push as I bought a 2004 and 2005 MINI from this dealer...

I like the brakes, now and will track this car frequently, makes me think about trying to buy a set of front calipers used/cheap from someone who upgraded to bbk, and rebuild and replace as needed, swop back and forth..

thanks guys...

Matt

 

Is there anything to be aware of relative to the parking brake adjustment when replacing the dust boots on the rear calipers?

 

Let me resurrect this thread for a moment. Maybe some insight will be gained.
I am rebuilding my calipers ('04) and have gotten the seal kits from carpartswarehouse. The front seals are pretty straightforward. The rear seal kit came w/4 parts:
The boot
The piston seal
An O ring
and another little boot/O-ring/seal thingy (designated hereafter as the "thingamabob"

I can't figure out wher the O-ring goes. Help?

The thingamabob goes on a guide for the piston down in the cylinder. Has anyone r/r'd this thing? How do you do it? It is a pretty cramped area.
Does anyone have an exploded diagram of the caliper unit itself?

Thanks!

 

are for the seals on the parking brake mechanism. don't have any diagrams for how it goes together though....

Matt