Brake Caliper Repair help needed.

To all...
I have the front caliper sitting on my workbench and just wanted to make sure of the re-assembly procedure.
1- Piston get cleaned with denatured alcohol and dried off...can I use
brake parts cleaner instead. Piston wall looks pretty clean...is there any need to polish ??? If it was dirty..what does one use to polish?? emery cloth ??
2- Piston seal is lubed with brake fluid and inserted. Or should it be inserted dry and then lubed.
3. Piston boot goes into counterbore first and then piston is inserted and then the boot seal is pressed into the bore.... is this the correct sequence ?
4. Can I use an approriate size socket to press the piston back into the bore. What tool should be used.
5. A tech tip suggested introducting air flow into the brake bleeder screw would make piston insertion easier. Is this a good tip ??
6. Is there a way to test for leakage past piston, just to make sure that seal was not twisted during piston insertion.
Thanks in advance for your help !!!
Peter (learning auto mechanics one step at a time).
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Peter wrote:

Yes.
Not if it's clean.

I prefer to insert it dry and then lube the inner surface (surface that will seal against the piston), but you could do it either way.

I find it easier to install the piston dust seal "onto" the piston and then press the piston into place. Once you have the piston close to the bottom of the bore, you can then press the dust seal into it's bore. There are special tools to press them into the bore, but you can get away with large blunt ended blade screwdrivers. The only thing is that it is extremely easy to poke a hole in the seal, then you are screwed and need a new one.You can also use brake fluid on the outside diameter of the dust boot, makes it easier to install in "it's" bore.

I use a large enough C-clamp and line up the piston, apply a slight amount of pressure with the clamp and then rock the piston as you start to apply more pressure.

That doesn't make much sense for insertion, I will use compressed air to blow the piston out of the bore. Again, some common sense is required here....you want something to stop the pistons movement as it comes out of the bore....piece of wood, a couple of rags bunched up...etc. Just don't get your fingers in there...that would be regrettable.

If you are careful and apply small, smooth pressure to the piston while rocking the piston (make sure you lubed the piston surface with brake fluid), you should have no problems. I've never personally rolled a seal over yet.
Ian
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***Agree with Ian. But if you DO need to polish, dont use emery cloth. Use crocus cloth.

****Nope. I have seen people put vacuum on the bleeder to help suck the piston in, but have not needed it myself.
And they taught us---all too many years ago---never to use air pressure to push the piston out. It works, but there is a safety hazard involved with using compressed air in this way. We used a liquid pump with brake fluid to pump out the piston.
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Thanks for the technical advice Ian .... everything went together nice and smooth...operates flawlessly.
Thanks again for taking the time to explain the procedure. It's good to learn how to repair things correctly the first time instead of through trial and error. This forum is a great help in learning the basics and moving on to new repair challenges !!
Peter
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Peter wrote:

Hey, no problem! Glad it worked out for you.
Ian
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