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View Full Version : Rear SE-i Caliper Rebuild Notes and Addenda



Dr_Snooz
01-17-2010, 09:21 PM
Further to the rear caliper rebuild how-to (http://www.3geez.com/forum/showthread.php?t=46522), the piston comes out nicely with a little compressed air blown into the brake line hole. Keep something in front of it to catch it or it will sail across the shop and get dented. Don't use your finger or it will get pinched and wedged, and only a lot of swearing will get it free. Don't ask how I know this...

After you remove the piston, there is a snap ring at the bottom of this hole. (Per below, do NOT remove this snap ring)

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00101.jpg

The snap ring is a real b!tch to get out and the homemade snap ring pliers below were the only thing I could get to work.

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00103.jpg

It's just a cheapy $4 needle nose from Harbor Freight that I ground down with a Dremel tool. None of these others worked.

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00113.jpg

The assembly below the snap ring falls out with a little wiggling and banging of the caliper face down on the work bench. That said, you shouldn't remove the lower snap ring or anything below unless you really have to. There is a special seal down there that needs to be changed and it's not in your kit, nor is it likely to be available anymore. Just clean everything as best you can with brake fluid and call it a day. That way you won't need the special tool or the odd seal.

The parking brake mechanism still works on mine, so I left that entirely alone. There's another special seal there that you probably won't be able to find anymore if you decide to take it apart.

This is in the how-to, but bears repeating. This is the best way to install the new dust seal:

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00104.jpg

Slip it over the lower end of the piston and then into the body of the caliper and screw it gently in. You'll want to slather the piston in brake fluid good before you do this.

The manual doesn't seem to cover this part at all so here you go. The piston itself is comprised of five parts, the piston itself, a spring, a special washer, a block shaped "thing" and a snap ring (see below).

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00108.jpg

The only real way to reinstall it is on this wise. Put in the block "thing", then the spring, the special washer and the snap ring. The snap ring seats far down in the piston and you'll need a socket to do it.

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00109.jpg

You'll be tempted to grab the first socket that appears to fit, pop it in a vise and jam it home. The piston body tapers however, and doing this will get you a socket wedged in the piston body. My 5/8" socket was the only one that would fit far down enough to seat the snap ring. BUT! It is also too narrow to seat well on the snap ring. If you just pop a 5/8" socket on and hammer down on the vise, the socket will slip off the ends of the snap ring, deform it and render it useless. So skip the vise. Carefully position the socket to cover as much of the snap ring as possible. Then manually press the snap ring in with your hand. If you are my weight, it will take nearly all your body weight and will leave you with one of these:

http://i441.photobucket.com/albums/qq132/dr_snooz/SNC00117.jpg

Woohoo!

Hope that helps someone.

nswst8
01-18-2010, 12:33 AM
Good job! Thanks for the "How to"

dacantu
01-18-2010, 01:09 AM
thanks snooz. keep us updated.

carotman
01-18-2010, 11:05 AM
This will be useful info when I decide to rebuild my calipers.

(do not remove that snap ring... do not remove that snap ring...)

2ndGenGuy
01-18-2010, 11:40 AM
Here's a nice video I made on the force the compressed air will create when shooting out that cylinder... Do NOT put your finger in front of it, like Dr Snooz said. You can end up with your finger broken easily.

http://www.youtube.com/watch?v=oN0zCcRgSxQ

Also, don't forget your brake cylinder hone to clean out any rough edges and nicks that will wear out your freshly installed seals.

Dr_Snooz
01-18-2010, 07:55 PM
Also, don't forget your brake cylinder hone to clean out any rough edges and nicks that will wear out your freshly installed seals.

Ooo. That's a new one to me. I'll just have to remember that for the next time I rebuild them.

2ndGenGuy
01-18-2010, 10:52 PM
^^^ Indeed, if they weren't bad, they probably will be fine. Just another extra step to freshen them up some more. I don't think most people do it, but it's pretty easy with the little berry hone you pop in your drill. :)

mykwikcoupe
01-20-2010, 09:35 AM
When I rebiult mine the last time my compressed air at 150psi wouldnt get the piston to budge. i used the brakes from my motorcycle to carfully press it out the same fashion it works as when on the car. the cool part about it is as the brake fluid presses the piston out it eases out very slowly and since you have control with a lever you can change how much pressure is applied as the piston gets closer to the end of seat.

You will obviously need to rebleed the motorcycle system but mine needed fresh fluid anyways.

My calipers were in good shape and the pistons were in good shape still chrome. I just repalced seals and did a full paint job to them.

Dr_Snooz
01-20-2010, 10:06 PM
When I rebiult mine the last time my compressed air at 150psi wouldnt get the piston to budge. i used the brakes from my motorcycle to carfully press it out the same fashion it works as when on the car. the cool part about it is as the brake fluid presses the piston out it eases out very slowly and since you have control with a lever you can change how much pressure is applied as the piston gets closer to the end of seat.

You will obviously need to rebleed the motorcycle system but mine needed fresh fluid anyways.

My calipers were in good shape and the pistons were in good shape still chrome. I just repalced seals and did a full paint job to them.

Trippy. Were they seized? Mine were seized when I got them, but a couple shots of PB Blaster and they came right out. I was surprised to find no rust or really any wear to peak of on the pistons.