Caliper piston reset

[audi314]

I have a set of front calipers that I am going to be putting on my B6 A4. I am trying to reset the pistons, and for some reason they arent budging. There is no bleeder screw in and all the fluid has been drained. What could be holding them in place? Or is there a method that I am just not aware of? Any help is much appreciated.


Thanks in advance!

[VR4-S4]

If i remember correctly they should just push in. I dont think they are twist in pistons...might want to try that

[archimense]

You only need to twist in the pistons for the rear calipers because of the parking brake mechanism. The front pistons should just be pushed straight in.

[audi314]

I tried channel locks to push them back in, and its a no go. Do you think that they might be seized all the way out? Is there a DIY on a rebuild for the calipers?

[Jsmooth65]

Squeeze with vise.

[audi314]

^^ Ah thats a good idea. I will have to take them to work in the morning and try that. I hope that I dont damage them!

[pdq 5oh]

If the pistons are stuck that bad, forcing them in won't leave you with good calipers. The pistons have to move back in some when you release the brakes. I'd bet the pistons won't return and will keep the pads applied somewhat. Brake fluid attracts moisture. If the calipers were emptied, and the bleeders left out, the bores are most likely rusty. Rebuild them if the bores and pistons are in good enough shape.