Some say that if the piston is shot, don't bother trying to sand it clean...others say that's fine(ish).
You need to blow the piston out somehow...with compressed air, or before you remove it from car...remove pads, put some wood in caliper and press the pedal.
Remanned caliper is not expensive, and if piston is rusted, might be the way to go (pistons are expensive(ish))
Dmax,
Thanks for your input. My calipers are fine. I was going to disassemble them sometime soon to powder coat them. Maybe ill just pick up a cheap set to coat instead of trying to bang it out in an afternoon.
Yeah I'd recommend buying reman calipers if your mileage is near or above 100k miles. At that point the seals in them will probably need replaces soonish and they will be much easier to prep than old used one that are on your car.
I have no pics but I have broken down and repaired calipers in the past without much issue. The rubber boot around the piston tends to fracture, water gets in and can cause rust to form on the exposed piston. If you look at the exploded view for my car the expensive component is the housing. Item 10, REPAIR SET BRAKE CALIPER kit, appears to contain piston, seal and rubber boot for $25, although I would clarify the presence of the piston. The fact that the kit exists is a reasonable indicator that repair is an option to resolving issues. In my case, some years ago, I purchased the seal and the rubber boot. The existing piston was still servicable once the rust on the exposed surface was removed. There was no scoring or pitting on the significant faces. You need to be scrupulously clean when reassembling of course. So I would give the repair a go. Its not that difficult.
.... Item 10, REPAIR SET BRAKE CALIPER kit, appears to contain piston, seal and rubber boot for $25, although I would clarify the presence of the piston.
The OEM rebuilt kit is the cover boot and the o-ring seal. The boot is really thin and can easily get damaged if not inserted properly. Additional rebuilt items for the calipers are the guide pins along with their plastic covers and cap.
The only difficult thing in re-building a caliper is to properly seat the cover boot. Best way is to utilize a tube at the exact diameter with not sharp ends and gently tap it in place.
The only difficult thing in re-building a caliper is to properly seat the cover boot. Best way is to utilize a tube at the exact diameter with not sharp ends and gently tap it in place.
Remans don't come with the carrier, do they? So that will still be rusty. I like the black caliper paint, sticks to old calipers pretty well and newer remans even better. Remans will probably get ugly faster because they've likely been sandblasted to remove grime.
Powder coating is a heat barrier, so I'd call that a bad idea. I also think it'll look like crap.
I had some extra pink house paint left over and used that on my calipers. Some fanatic here from London mentioned that he'd used house paint on his paint, so I figured it'd be fine on calipers.
On a green car yet. That week, I can't tell you how much the ladies loved it. Pink calipers, green tires, green body (fern green metallic). My car was hideous...even worse than it is now. Still, they came.
Part of that is probably because of my looks and personality, but I think about 89% of the credit goes to my calipers.
I'm very serious. Pink. There's a Captain in the military here that does that too...and I think for the same reason.
Don't make a thread about it...don't ask...just do it. All four corners.
The guys at meets will hate it. Let them hate while the ladies hound you. Do not tell anyone. Don't speak of this again...let the thread die.
How do you attach the hose from the air compressor to the caliper to blow the piston out? My piston doesn't come out of the caliper using the method which requires you to pump the brakes.
Pumping the brakes to remove the piston will have fluid all over the place. Take the cap off the reservoir, put some cling film over the opening and replace the cap. Remove the rubber boot from the piston. Then open the bleed screw on the caliper and you will be able to ease the piston out. Use two screw drivers oppositely oppose on the lip of the piston. Replace the seal inside the housing and slide the piston back into place. Replace or refit the boot. Close the bleed screw. Fit the pads. Remount the caliper. Remove the cling film from the reservoir and bleed as normal. Focus on being clean throughout.
I can't figure out why the saran wrap is necessary either. If you want to let the piston displace then you just need to open the bleed screw to pull it out. That will let air in instead of pulling fluid from the reservoir. It will probably still be quite difficult. If you're going to rebuild you could use water pressure on the caliper piston. Hook up a fitting to the brake like port on the caliper and turn on the water. 60 psi can probably do it. Shop air will be definitely do it though.
No luck. It moved a little bit but it seems to be stuck. I keep trying my hardest to pry it out but it won't move and I end up hitting my knuckles against the caliper. I guess this way isn't an option. Gonna go look for an adapter so I can hook it up to the compressor, I doubt I'd find one anywhere.
Ok. I'm surprised. Was this caliper in service? Can you buy an adapter for this sort of purpose? You could go to a breaker yard and get an old brake pipe, fit it to the caliper and then attach the other end to a foot pump with a hose clip.
My uncle took it to the Auto-Body shop he works at and managed to get it out. Finally! Now I just have to wait for the gaskets and clean it out and rebuild it.
How did he get it out? Was it just the rust keeping it in?
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