How To Rebuild A Brake Caliper (New piston, seals etc) 

you can also pump the brakes to pop it out that's what I did. great video

Nice video George. Just a little tip.. when installing outer dust boot it is easier to put boot on lip when the piston is out of calliper. Slide boot to the lower edge of piston and then slide the piston trough boot.

Great video George! When I watch British car repair vids I’m amazed by the rust, but then I remember you’re an island nation surrounded by salt water.

it is VERY easy to tear or puncture the seal. once you get piston in with seal, use an airline to pressurise the boot. This will make it expand enough to seat itself on the caliper. This is the only way which worked for me. Also remember to make good the points where the pad edges contact the caliper. Rust stops the pads moving in when they wear which side-loads the piston to the point where it seizes.

It's very important to point out that you should NEVER use any type of grease on rubber seals except for silicone based grease.any Petroleum based grease WILL cause the rubber seals to swell and cause the caliper to stick/seize.

Great to see someone repairing. Any Muppet can bolt a new part on. I prefer to repair not replace.

Did mine today but after bleeding and going for a test drive I found the brakes to be pretty spongey and unresponsive. They can just barely provide enough force to engage ABS when I really floor the brake pedal, but they used to lock up much sooner. I'm wondering if I should have filled the cylinders with brake fluid before reattaching the brake line, as I'm not sure if the bleeding process is able to get all the air out of the cylinder. It's also possible that the old pistons were just not retracting very far, thus reducing the travel needed to do hard braking (in other words, what I feel as "spongey" is actually how they should feel and I am just used to sticky brakes).

Your videos are the best for guys like me (amateurs), every details well explained. Thank you Bro!

Best to put boot on inner end of the piston and seat seal while it's on the piston before pushing it in .then push piston trew New boot only takes seconds and no screwdriver stuffin needed

next time try to blow some air with compressor. It will push piston out of calliper in seconds. Just be careful with your fingers cuz it pops out quickly and piston bumps into calliper wall. Ask me how I know

Great video, very clear on the procedure. I resealed all of my callipers last year and this year I am starting on the fronts with new callipers, painted and new discs and pads so will be watching out for your video on the discs and pads changes to get some more great tips. Keep up the great work George.

I'm doing mine now on the front, can't get the outer boot on caliper it seems real tight

Maybe a small tip out of 100s 😂, maybe a skinny screwdriver pushed down the bleeder screw hole to push the piston. Also cheers. Looks really easy, gonna do mine soon now, cheers

Good job George! I have Discovered you bevause of timming chain for my n47. You have no ideea how much it helped me that series. Greetings from Sweden.

I have been waiting for this video for a while. Again, very detailed video. I love it! Thank you!

Another fantastic video - great, clear explanation of work needed and work carried out. I use silicon grease on the slider pins of my brake calipers. I would be confident to strip down the calipers on my brakes after watching your video. Thank you.

I use an airline to pop the piston out

Hey, nice video thank you for helping me and my e87 250.000km ! I’m from Belgium but nobody does that as well as you in French 😂

Literally saved my life thank you!

Brakes 😬. You have done great job mate! Keep it going 👍

I have same issue new to doing me mechanicals on my car?

My gf and I love watching you lubricate pistons.

Compressed air will pop a stuck piston out.

I have the same caliber and the same metal ring came off when I took away the old piston boot. I just can't understand how to pop the new boot in, because there's no groove where to pop it in 🤔. It just comes right off if push it all the way in, because there's nothing retaining it.

for some reason i cannot even get that inner seal back in it just wants to keep popping out on the opposite side i have in. IDK What to do??

Great video. I dunno how you got that last lip in that’s currently where I am stuck. However I didn’t use any grease and I think the kit is not an exact fit. Getting the caliper cylinder in was a bit difficult also but getting it out was a breeze. I sprayed compressed air in the brake line hole and it popped right out 😂 used wood blocks to catch it of course. I was also wondering if I soak this in degreaser can it damage any of the internal components?

Thanks for sharing George, they get in bad nick at times eh

Where do you find the rebuild kits? Ebay best bet?

Why didn't you blow the piston out with compressed air? Out of curiosity... That's how I always do it

Oh for crying out loud, you're a life-saver (if I haven't botched up the job too much already). I was under the impression that no grease was compatible with brake fluid so I only used brake fluid to lubricate the O-ring and piston surface. Now the piston is in crooked. I'll bet if I used some of that red rubber grease, I wouldn't have had such a problem sliding the piston past the O-ring. Be careful when you Google "red rubber grease" because a lot of the results will be that Lucas Red "N Tacky grease which is something different. I see off to the side that Castrol sells a "Red Rubber Grease". I've seen it in a Castrol container and in a white container on Amazon. Now I've got to get me some and hope I can remove the jammed piston from the caliper without destroying the new rubber dust cover. Actually, why not destroy it. They're cheap. Thanks for posting your video otherwise I would never have known about that red rubber grease.

good job, my rear pad is grinding metal on metal because it wont retract

I had to do the same in my 120d.

Why the hell didn't you use air on the bleeder hole and blow out the Piston 😢

great video mate

Hi George. Great video, just curious where you got the parts from? Ie the piston itself, did it come as a complete kit. The biggish places I've tried don't sell them and BMW only sell the piston as part of the main caliper so it becomes really expensive!

Great video George! Love the step by step process

Good video mate, i don’t do value or rebuilds due to the extra time needed, but if they’re cheap enough you’ve given me something else to think of!. Good luck In your RU-vid venture

Hi George, Where did you find the rubber plug you have on the end of the brake hose? I have been looking for something like that a while. This will remove the need to have something clamping down on the hose.

Hey. Where I can get this cap for dripping brake fluid? Super video

George, another excellent and very informative video, Are you a mechanic by trade? Just found your channel recently and I’m well impressed with your knowledge and tips.

Hi george thanks for your video, I am trying to fit out piston boot and it will not fit no matter how hard I try, what else could I try?

Did u have to bleed the brakes after installation.?

Do bmw sell those pistons oem? Or you buy them aftermarket? Cheers

Vídeo muito bem explicado parabéns 👏

... and this is the trickiest bit... ...so here's one I did earlier... Me: Dammit!

How many miles?

Great detailed video as always. Cheers 👍👍

Great Job 👏🏼 - I would have greased the inside of the piston housing too. To get a bit more grease in. Keep up the cool vids ✊🏼

Bmw want them dry to extend the life of the caliper...🤣🤣🤣

Nice video. Do the rear rotors need doing ?

Great job

Nice video George, Where did you get the brake line caps from?

Great video, just one question, how do you get the trapped air out from the callipers?

Thanks, that was very helpful. Do u have to bleed the brakes after reinstalling the caliper?

Great job!👊👍

Great vid as always 👌🏻 Did u have to bleed the brakes when you re installed the calipers?

Very nice video, Thanks!

Great vid George

Really great video you make it look so easy 10out10 nice one George peace

Cool video George man

No bleed process?

Good but cant believe you didnt clean the calipers up more and paint them ??

Where can i get these caps that stop brake fluid from leaking?

great job

does it drive a lot better?

Nice video yet again George. Where do you get the orange gloves from? Are they expensive for a box of 100

🙌🏼

Only use brake fluid when you rebuilt the caliper, nothing else, you have already contaminated your oil with grease.

The intent was fine, the advice is bad. Don't grease the pistons or piston bores. You will contaminate the brake system and fluid by doing so. If lubrication is needed, use the correct brake fluid for your car, fresh of course. And do not use grease on slide pins or anything rubber. Silicone paste should be the only lubricant that touches rubber, and same with slide pins. Silicone or ceramic only. I've seen this mistake made too many times. You will be buying new calipers and brackets if you do the same.

stick a shim and pump the brake next time works like a charm

My car has not even got over 3k miles & i have alredy changed brake disck brake pads & both front caliper & handbrake wires 🤨 & o it is not a bmw...

instructions unclear: i popped the caps but got arrested....

You didn't bleed the refurbed calipers before declaring the job was done. I can just see an inexperienced DIYer following your video and then taking the car for a spin with no brakes.

the pads and rotors were done on that car, putting them back on was retarded, also outer seal should be set in then piston placed through it, this video shows what not to do

I don’t understand how can you take the caliper off and not even clean it good! Lazy? Is like you buy new clothes and don’t have a shower. I hope that’s not for a client, that’s one of the reasons to DIY and never trust mechanics.

What a waste of life , waiting for the ads to finish