Elementary? Maybe step-by-step narrative will help someone else.
1. Piston removal. One of the two pistons would not budge after removing the caliper. Solution: put the caliper back on the car with the pads removed, reattach the brake line, insert some wood shims so the piston that DOES move will not come out of the bore, and use the hydraulic system to push the stuck piston out. I had to push the 'stuck" piston back into the bore several times, but eventually it moved far enough out to allow me to use a channel locks to grab the edge of the piston and rotate it until I could get it out of the bore. Note that I split the caliper halves. Perhaps with a brake piston pliers (like below, said to be available at Home Depot for ~$60.00 US) this would not be necessary.
2. New seals. Nothing fancy here. Use a pick to remove old ones, clean the bores and passages with brake clean, shop rags, and compressed air, lubricate the new seals with brake fluid and put them in place. I got rebuild kits FTE RKS4202 from PMB Performance, 372 Winchester St., Murray, UT 84107 USA. Tel. # 1-855.786-7101, The kit does not include new pistons.
3. So, the pistons don't slide in by hand, like so many of the YouTube videos show, The new seals which are not tapered but probably take a "set" with use create a lot of friction. So push the piston in with a C-clamp or a pad spreader repurposed.
So here's where we are. Got the piston started and spent a lot of time creating my substitute for the BMW tool to orient the piston that supposedly quiets the brakes, not that the Blue Bible tells you why this is so important (if it really is).
4. Here's how my expensive 3.9314 - 0600.1 tool is used.
5. But what about the darn dust boot? More YouTubes that don't really seem to answer the problem. And some guys have done it so often that they are not inclined to be, uh, too helpful. I tried getting it on with the piston in place, but that was not gonna happen. So I took the piston out and put the boot on the piston.
6. Put the booted piston back in the bore and press it in -- all the way in -- with a C-clamp held in a vice.
7. With the piston all the way in, the dust boots edge fits down in the groove and the retaining ring can be spread and slipped on.
8. If the piston needs to be rotated, move it out with compressed air and use the channel locks.
I used to write laboratory manuals for college biology students. Never assume knowledge of anything. And there is no such thing as a dumb question. We are all ignorant until we aren't any longer.
1. Piston removal. One of the two pistons would not budge after removing the caliper. Solution: put the caliper back on the car with the pads removed, reattach the brake line, insert some wood shims so the piston that DOES move will not come out of the bore, and use the hydraulic system to push the stuck piston out. I had to push the 'stuck" piston back into the bore several times, but eventually it moved far enough out to allow me to use a channel locks to grab the edge of the piston and rotate it until I could get it out of the bore. Note that I split the caliper halves. Perhaps with a brake piston pliers (like below, said to be available at Home Depot for ~$60.00 US) this would not be necessary.
2. New seals. Nothing fancy here. Use a pick to remove old ones, clean the bores and passages with brake clean, shop rags, and compressed air, lubricate the new seals with brake fluid and put them in place. I got rebuild kits FTE RKS4202 from PMB Performance, 372 Winchester St., Murray, UT 84107 USA. Tel. # 1-855.786-7101, The kit does not include new pistons.
3. So, the pistons don't slide in by hand, like so many of the YouTube videos show, The new seals which are not tapered but probably take a "set" with use create a lot of friction. So push the piston in with a C-clamp or a pad spreader repurposed.
So here's where we are. Got the piston started and spent a lot of time creating my substitute for the BMW tool to orient the piston that supposedly quiets the brakes, not that the Blue Bible tells you why this is so important (if it really is).
5. But what about the darn dust boot? More YouTubes that don't really seem to answer the problem. And some guys have done it so often that they are not inclined to be, uh, too helpful. I tried getting it on with the piston in place, but that was not gonna happen. So I took the piston out and put the boot on the piston.
6. Put the booted piston back in the bore and press it in -- all the way in -- with a C-clamp held in a vice.
7. With the piston all the way in, the dust boots edge fits down in the groove and the retaining ring can be spread and slipped on.
8. If the piston needs to be rotated, move it out with compressed air and use the channel locks.
I used to write laboratory manuals for college biology students. Never assume knowledge of anything. And there is no such thing as a dumb question. We are all ignorant until we aren't any longer.