Has anyone re-built calipers? cant get the boot on!
 

I gave up after about 2 hours, I can NOT get the boot grove to slip into the caliper side.

People on YouTube say they use there finger nails or screw driver?? The closest I got was the top part shoved in but then its all bunched up at the bottom (like its too big) and then its impossible to work on. I have the right boot, matched up to the old, even tried getting the old boot on - the same situation.

The boot fits in the grove fine without the piston, tried getting the piston in after the boot was slipped into the caliper, but that didn't work.

There has got to be a trick to get this on, has anyone done this??

I am using brake fluid as lube.

I did the Brake Hydraulic Overhaul in my 1998 528i (E39) a few years ago.
I wrote up all the tricks in that thread.

Take your time to read through it...

DIY: 1998 BMW 528i Brake Hydraulic System Overhaul (6 Hoses, Caliper Seals/Boots) - Bimmerfest - BMW Forums

Further to the link above, I will summarize for you...

- Install the Piston Seal.

- Install the boot on the caliper side first.

- Now slide the piston in slowly, making sure it sits squarely on the seal (i.e., don't fold the seal over!).

- Once the piston is pushed all the way in, you will hear a faint "pop", that is when the boot's inner lip slides onto the piston's groove.

THANK YOU!

I get it now. caliper grove first with it stretched over the piston without piston grove attached. Too difficult to get the piston stretched in while its attached to the caliper, it has to be slid down to the opposite end of the grove on the piston then attached to the grove on the caliper.

THANK YOU!

cn90 - Nice write up on the 528 brake rebuild. I used your process and images when rebuilding my own X5 brake system. Thanks for the re-posted link.
:thumbup:

You have to move east

Glad you got it. The lube to use is "red rubber grease".

I've taken out the bleeder screw and use air to "pop" the seal into place as well. It has been a long time since I've done that though, but I recall that being the easiest. An ex-BMW mechanic showed me the trick on my E36 after I cursed my way through the first set.