brake caliper rebuild/rebush

[markb]

with the poor weather conditions in new england it's pretty common to find the brake calipers frozen on their mounting pins. in honda's wisdom they mounted the calipers using steel pins riding in steel bushings that are pressed into the aluminum caliper with those near worthless rubber boots protecting them.
some symptoms of frozen calipers are loss of braking power,one pad worn more than the other, disc bending when you push on the brake pedal, and pads worn on an angle from top to bottom.
to do the following you need access to a simple lathe to make the bushings since they aren't readily available,but it is all basic lathe work.
i don't have pictures of drilling the old pin out because i didn't have a camera then but you must be pretty carefull so you don't ruin the caliper. you must hold the caliper in a vise on a drill press and locate the center of the pin using the hex in the center. you can do this 2 ways one is by using your 1/2 in bit and aligning it by eye then lightly kissing the top of the pin and adjusting your location so the bit is cutting evenly around the hex. the other way would be to put a drill bit in the drill chuck upside down that just fits into the hex.(i'll list this size later) using the 1/2in drill in the .54 dia pin gives you some safety margin so you don't hit the caliper. now use a punch to drive out the remaining pin. now you have to drive the metal sleeve out if the caliper. the first pic shows the bushing almost driven out and the mandrel used to drive it. the mandrel has a .551 by .12 long pilot to locate the bushing and the body of the driver is .605dia by 1.44 long. i think you would damage the caliper by using a press to knock the bushing out so i held the caliper in my hand and whacked the mandrel with a hammer. the bushing must be driven out in the direction shown.
the other thing this shot shows is the piston puck,it's kinda like an asbestos disc. this piece is very important as it insulates the piston and brake fluid from the hot pads. without this piece you will boil your brake fluid, the bad part is that honda doesn't sell just that piece. i'm gonna order some glass reinforced teflon and see if it works in this application.i'll let you know

[markb]

whoops here it is

[markb]

this one shows the replacement bronze bushing being driven in, and a new honda steel pin for the rear p/n 45115-166-004. you can make the bushing from brass or bronze i used bronze oilites that i had but brass would be easier. the rear bushing is .61 dia by .7 long with an i.d. of .553. the bushing for the front is .61 o.d. 1" long and the i.d. is .553 again. this will press nicely into the caliper but if it's loose you can loctite it, use green. if this was all you did it would be worlds better than stock but i made stainless pins also cause i really don't wan't to deal with this again.

[200x_Basket]

looks great but beyond most of us. why dont you take some orders and sell your work. i will take two sets for a 250r if the price is fair.
thanks
chris

[markb]

this one shows the piston and seals out of the caliper. if you use air to remove the piston be very carefull that thing comes out like a shot and is pretty heavy. use something like a dental pick to get the seals out and be carefull not to scratch anything. the usual culprit is the first seal, the dust seal. the groove it sits in builds up a white chalky corrosion, you MUST get this all out or the seal will fail over time. i use a small electronics type screw driver that i sand the rough edges with 220 sand paper to keep it from scratching(very bad thing). only use fresh brake fluid to install the seals and lube the piston NOT OIL. after you put each new seal in wet your finger with fluid and use medium pressure as you run your finger around the seal feeling for any bumps. if there are even tiny bumps carefully remove the seal and clean what you missed. in the rear there is also a small o-ring p/n 91358-964-006 that i usually replace since it's as critical as the big ones. the small pin that mounts the calipers in the rubber bushing is almost never a problem with corrosion but the rubber can break, it's p/n45132-166-016

[markb]

i 'm showing this pic so you can see how thin the original steel bushing is. it's only .03 thick so you might not think it's even there, if the bushing is out, the hole in the caliper should measure about .61". this also shows the replacement stainless pin i made that i still have to thread. i had to put the hex piece on the end because i can't broach internal hex's.
mark

[250sx]

do mine! do mine! :hail: :hail: :hail:

[jenndnn3]

Great Job Mark.....I had the same exact issue on mine on 200x...and because of that have yet to do my front. Oh well who needs a front brake lol. I like the idea of replacing with better stuff. My hardest thing i ran into actually was not getting the pin out...it was rusted good, I actually saved the sleeve but not the hex I kinda strip it in the process.But to put the rubber boots back in. They are they worst to put back on. I actually ended up useing chemicals and a hammer to get the slide out. After I found out that part actually floated, before I started on my brakes I didnt know it slid out. I probably could have saved the hex too. I am surprised you are unable to order seprate parts, I was able to order my parts individually. Cost $15, for rubber and hex.

[250rAL]

I haven't had any trouble with the mounting pins yet, but the first time I went to replace the pads, the bolts wouldn't budge. Had to end up drilling the bolts out. I went ahead and took the threads in the caliper too and drilled all the way out the other side of the caliper. Then I just used stainless bolts and nuts to retain the pads. Now it's easy to replace the pads.

[markb]

jenn your right you can get the pieces except for the round puck in the first pic, they make you buy the piston to get that piece. this really stinks cause like i said that piece is critical.
i'll price out doing the conversion and post it, i didn't really intend to sell it but as i was endlessly typing out the procedure it finally dawned on me that alot of people can't do it. if i post something like this i'll include the #'s i used so if you can make it for your own use please do so.
basket: the 250 is a little different animal, it can be done as i have installed a first revision on mine. the problem i noticed with the 2 pot caliper is that when you push the sleeve out it tends to take a little material with it. the trick is that until you remove it there's no way to tell how big to make the od of the bushing. you want to make sure that the sleeve is a good press fit in the caliper so the wear occurs between the pin and sleeve.
mark:lala:

[200x_Basket]

come up with a price and i will ship you my caliper:headbang: