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General Category => General Discussion => Topic started by: Scout63 on November 30, 2021, 08:29:25 PM
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Any good tips for removing a stuck brake piston from the caliper? They are Brembo F08s. I usually use a little compressed air while assembled, which moves the less stick one out, then disassemble, put my finger over the hole and use compressed air again to try to get the other piston out. It just gives me the willies thinking my finger is so close to the piston. Is there a better way?
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Screw a grease fitting in place of the bleed screw, pump the caliper full of grease.
Use a small C-clamp to hold the non-stuck piston in place.
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Screw a grease fitting in place of the bleed screw, pump the caliper full of grease.
Use a small C-clamp to hold the non-stuck piston in place.
+1
I would try to pump them out with the master cylinder first. Then go with the grease gun. It is amazing to me how much pressure a grease gun can generate. Of course you're left with a bit of a mess to clean.
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When using compressed air to remove the piston, I wrap an old towel around the caliper half several times, so that when it does come out, it won't go flying across the shop.
Heating the alloy caliper half will help if the piston is an original steel one.
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Thanks everyone. I think I might use a c clamp and rubber to block the fluid passage as well.
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Sometimes the steel piston is so corroded that no measure of pressure, compressed air or grease will budge it. As a last resort I weld the tip of an old bolt to the centre of piston and let it cool. Attaching a wrench to the bolt head I then turn the bolt / piston out, works every time.
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Sometimes the steel piston is so corroded that no measure of pressure, compressed air or grease will budge it. As a last resort I weld the tip of an old bolt to the centre of piston and let it cool. Attaching a wrench to the bolt head I then turn the bolt / piston out, works every time.
If a steel piston is that far gone, isn't the caliper's aluminum also toast?
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I don’t think it’s very far gone. The other piston popped right out with pretty good fluid still behind it. The caliper body looks good with nice paint. The bleed screws came right out. I was feeling a little timid and put it down for another night. Expelling brake pistons with air is up there with seating tire beads for causing anxiety.
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If a steel piston is that far gone, isn't the caliper's aluminum also toast?
The caliper bore only guides and secures the piston when braking. As long as the piston is a slip fit in the bore the caliper will function as intended.
BUT: The seal between the caliper and the puck is maintained by the square sectioned "O" ring. It is imperative that the surfaces between the "O" ring and the caliper body are smooth enough to seal. Being protected by the "O" these surfaces the surfaces of the groove are usually in excellent condition.
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I had an issue with a Kawasaki last year and made this video, may help
https://youtu.be/1GAg5IHcCBo
Gino
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I had an issue with a Kawasaki last year and made this video, may help
https://youtu.be/1GAg5IHcCBo
Gino
Thanks Gino. I’ve heard about that but never seen it done.
I used a small c clamp and a bit of inner tube to block the inner port, wrapped a towel around it like Charlie suggested, and a little compressed air popped it out.
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Thanks Gino. I’ve heard about that but never seen it done.
I used a small c clamp and a bit of inner tube to block the inner port, wrapped a towel around it like Charlie suggested, and a little compressed air popped it out.
Hi Ben
Compressed air works if its not too bad but sometimes if its too bad its worth keeping the grease trick up your sleeve
Gino
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Roger that Gino. You make it look so easy.