Rebuilding Calpiers

[bnuk]

There seems to be a consensus on the forums that it is extremely difficult to rebuild Honda calipers. A couple of years ago I had a rear caliper hang up and I really didn’t have $90 to drop on a rebuilt one, so went ahead and rebuilt it myself. Turns out, it ain’t so bad as long as you don’t mind making a bit of a mess. By now I have rebuilt all four calipers, so while I’m no expert but I have a pretty good feel for it. The kit I got is a Beck/Arnley kit off of rockauto.com, it costs $8 and one kit will do 2 calipers. If you need a new piston, I think there some kits out there that include a new piston. You don’t really need any more tools than what you need to change your brakes and it will probably take you an additional 30-90 minutes on top of what it takes you to change your brakes. Im not going to talk about taking the brakes apart, if you don’t how to do that, you probably shouldn’t be rebuilding your calipers. Front Brakes Before you remove the top bolt on the caliper you need to pop out the piston using the brake pressure. Swing both calipers upside down and put something underneath both calipers to collect the fluid. Make sure you have plenty of fluid and start pumping your brakes. If you have a caliper that somewhat frozen you may want to throw a C-clamp on the other caliper to make sure the frozen comes out first. (once one pops out you can’t get as much pressure on the other one.) Don’t worry about them flying across the room or anything, that only happens when you use compressed air. They probably won’t even come out all the way on their own. Once they are out or at least loose, carefully remove the banjo bolt and take the caliper to your bench. Rear Brakes Before you remove either caliper bolt loosen the banjo bolt holding the brake line in, and then take all the bolts out and take the caliper to your bench. For the rear calipers you just need to unscrew the piston. Now I have never been able to use needlenose pliers to unscrew these damn things, they are always way to stiff for that. I usually stick a screw driver in sideways and use that, or had to use a gaint 1" flat head attachment for a socket wrench when I did one of my rear calipers. Your piston should look this clean, if there is any major marring, scratches or rust you may want to toss the whole caliper. Same goes for the inside of the caliper. Pull the boot off of the caliper and then use a little screw drive or a knife and pull out the old piston seal. Take a flat head screwdriver and clean out the groove the boot was sitting in, the cleaner this is, the easier the next part will be. Make sure you clean all the bits of rust out of the caliper once you are done. Then you can put the new seal in… this is all easy stuff. Ok, now you are ready for the hard part. First take the boot and seat it in the groove inside the caliper without the piston just to get a feel for how it goes and how it looks and feels once it is in. You are going to want to put the boot over the top of the piston and then slide it all the way down so it is sticking off the bottom like a skirt. Then take the piston and put it so the back section of the boot sits in the groove first. From here you just have to work the boot all the way around the front so it is completely seted in the groove. This alone could take you twenty minutes so be patient. It gets easier with each one you do. I found it helps to use a little screwdriver on the rear calipers to help push the boot in (just be careful not to puncture the boot.), but on the front it was easier to just work it in by hand. You will be able to tell once it is in because you can pull up on the piston very lightly and the boot will stay in. For the rear, take the piston, push down and turn it clockwise to get it started, once it gets started it will lock the boot in. For the front just push it in as far as you can by hand, and then finish it with your C-clamp. Just make sure it is going in straight, if it gets stuck, it’s probably because it’s not straight. Pull out the caliper pins and if they look clean just replace the boots and put a little grease on them and stick them back in. Don’t go crazy with the grease, if you get too much it will squirt back out and put pressure on your new boots. Everything pretty much just goes back together now. Your rebuild kit should include some new crush washers for the banjo bolts, I apparently lost mine somewhere along the way but use ‘em if you got ‘em, and make sure you bleed them well and bleed them again after a day or two.

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[jeffberk]

Some considerations.
1) if you have a stuck piston, you can use compressed air, just put a c-clamp on the piston so it will only move so far and not shoot through your garage window.
2) It is generally a good idea to clean up the cylinder bore ether with a hone attachment for your drill or some crocus to make sure there are no imperfections.
3) Make sure you have a quick source for a replacement piston since you won't know if it's pitted until you have your caliper apart.
Thanks for the DIY, you are right, rebuilding is a lot easier than most people think and a bit more fun than just plug and play!

[fathergoat]

Nice, informative write up.

[arturogs]

tanks for you information

[nzeeman]

Is it necessary to remove and rebuild the whole caliper if you only need to replace the torn rubber piston boot? Can it be replaced without removing the caliper (and thus requiring bleeding)?

[bnuk]

yeah piston has to be removed because the way it is designed the piston really holds the boot in place.

[nzeeman]

I replaced the rear brake pads on my 2001 Accord EX coupe on 12/14/2007. The rotors did not need any attention so I simply replaced the pads, using the Honda OEM pads I bought at the Honda dealer. I do most of my own work, so this is no big deal for me; it's prety straight-forward stuff.

After a few days I noticed a 3/4" wide band of rust developing on the right rear rotor, on the outer surface of the rotor (you can see it without removing the wheel), toward the center of the rotor, alongside the hub of the rotor.

I cleaned it up with a small wire brush, cleaned off the rotor and the outer pad with brake cleaning solvent, dried them, and put it all back together. It looked clean for a few days but that band of rust started to form again. I cleaned it off again and lubed the sliding surfaces of the caliper assembly with appropriate brake lube, and checked to insure the caliper pins were moving in & out smoothly, which they were.

The rotor again looked OK for a while but the rust has started to form again after several days. It's almost as if the inner edge of the outer pad isn't contacting that area of the rotor and not "wiping" it clean.

Has anyone experienced this? Any ideas?

[bnuk]

if your rotor has a band of rust it most likely means you pad is not sitting flush to the rotor. did the pads just drop in or did you have to wedge them in? aside from the retaining clips the pads should sit in the caliper loosely. I've that sometimes I have to grind a little bit of the tabs on the end of the calipers in order for them to fit properly.

[nzeeman]

Hello, bnuk..................Thanks for the prompt reply. I'll take another look to make sure the pads are a loose fit. (nzeeman)

Another question; does one "COMPRESS" (with a c-clamp or similar screw-thread gadget) the rear caliper piston on the 2001 Accord EX or does one "ROTATE" the piston to make room for new pads?

[bnuk]

because of the ebrake mechanism you have to screw it in (anytime there is a slot or cross on the piston it is probably a screw-in.) manuals always show a pair of needle-nose pliers but thats bullshit. the best thing is a big (3/4" or 1" wide) screwdriver attachment for a socket wrench.

[nzeeman]

Thanks again! You lead the league in fast replies!

How do you keep from twisting the rubber boot when you're screwing in the piston? Will it cause any damage if you try to compress it?

I've compressed it with a brake pad spreader and it seemed to move easily, and I'm getting proper brake operation (I cleaned up that narrow band of rust we discussed earlier..thanks for the help).



Thanx!

[DonP]

props dude!