how in the world do you remove the caliper piston?!?!?!?!?

hey guys, i've got one of my calipers almost colpletely torn apart, and I cannot for the life of me figure our how to get the piston out... the service manual says to reove the dust seals and other misc seals, but i cannont find them... I though maybe you popped the circle parting behind the caliper off, but there's no lip... help please....

its a seca 750 fyi

and then i guesss how do you go about cleaning it and making sure it will work right?

 

I remove caliper pistons by removing the bleeder valve,inserting a blow gun nozzle,and shooting in a 100 lb or greater blast of compressed air. If you use this method,be sure to keep your fingers clear of the piston (unless you want to lose them). Also make sure the piston is facing away from you,as it may dislodge at high velocity. An alternate method of removal is to use a grease gun to fill the caliper,thus displacing the piston. Good luck,Schooter. Let us know how you make out.

 

wont that damage seals? im not looking to buy new seals and stuff, but i guess if thats ow the cookies gonna crumble, then i gotta roll with it.

thanks danno

 

Hey Scooter,
If the pistons are that hard to get out, the seals are not going to be salvagable. Get the caliper rebuild kits and do it properly, or you will have the joy of doing it again...
Personaly, any time the caliper is torn down, it gets a new set of seals. They are too easy to damage.

 

Re: how in the world do you remove the caliper piston?!?!?!?

No It won't hurt them. I use air like danno but put the whole caliper in a big towel. That way I don't have to look all over the garage to find the now damaged piston.
I don't replace the seals on my bikes every time unless they're leaking. I just make sure there's NOTHING in the grooves behind the rubber ring. I like to use a soft wire wheel in the grooves. Don't remove metal or scratch the bore. On reassembly lube the rings with brake fluid,don't force it.

 

on a bike that's been sitting and the piston is glued in with dried brake fluid, compressed air won't do it.

You can do it with your grease gun: block the bleed hole with an appropriately-sized metric screw; and fudge up an adapter for your grease gun from a union bolt. Pump the caliper full of grease until in "hydo locks" and then pump the piston out. Messy but effective.

 

ok, well i found a nice air tip with a tapered nozzle, threw on some electrical tape to make a nice seal, threw it in a towel, and pop!

so what should i do to clean it up in there and make sure it works properly?

and what about putting the piston back in?

 

clean the bore out very carefully, then use a Dremel or make yourself a hooked pick to get the two channels the seals sit in CLEAN.

The channels have to be religiously clean or the new seals won't sit properly.

lube up the new seals with brake fluid and fit them into their places; then lube the piston with brake fluid or the lube that came with the caliper kit and press it back in squarely. It will slide in with firm hand pressure.

 

kk thanks, I thought that brake fluid was all i could use, i remember somewhere saying anything else will damage the seals and what not

 

sometimes the caliper seal kit will come with a little packet of lube, you can use that or just brake fluid.

 

well i took em apart, got em nearly medically clean, and put them back in.. i didnt replace seal, they looked good, i took a flash light and looked for cracks and whatnot, couldnt see any, so i put em back in..

though, the more and more i browse this forum, the more i want to put like a fj600 front end on or something