I recently went to swap out the rear brake pads on my 90 FC convertible and ran across some problems. First of all, I was switching to Hawk HP brake pads. I have already switched out the front which , honestly , the only change I've noticed is a HUGE increase in brake dust on the rims. Anyway, back to the rear brakes... Everything was going smoothly until I put the new pads in place and tried to drop the caliper back into position over the pads. It wouldn't fit... Now I know the first thing you normally would do is to push the piston in as far as it would go on the caliper to give clearance for the new pad. However, even using a C clamp over the piston, we were unable to push the piston in far enough to clear the new pads. The next step I tried was to bleed off some of the pressure on the brake lines. Nothing seemed to work though...

Here's the big question: Why are there two release/bleeding valves on the rear ? What purpose would two valves serve... I tried releasing pressure via both and was never successful in releasing enough pressure that I could get the calipers back over the new pads. Is there a trick to doing what should have been a fairly straight forward pad swap ?

Thanks !

 

sounds like your calipers may have gone bad. not for sure on this because i'm no expert but the same thing happend on my lumina when i treied doing the rear calipers. and i had to drop 15 bucks for a set of used calipers from a local junkyard. so you could either do that or find the guy on e-bay who sells rebuilt calipers --btw he only sells rx-7 stuff.

good luck,
Matt

 

Marlaman, I would have thought that too EXCEPT that the calipers are working. In fact (and this seems like a valid test in my mind) I verified this by applying the emergency brake only after putting the old pads back on. Best I can tell the rear calipers are functioning fine other than quite a bit of squeeling...which is what lead me to believe in the first place that the pads might be low. Turns out they still have plenty of pad left. So there was no urgency to resolve this because I put the old pads back in and i'm in business now... It's just a really odd situation . Plus I can't figure out those damn TWO valves ... Anyway, thanks for the input. I should have specified that they do seem to be working.

 

I replaced rear pads on my vert recently and I did same mistake. You can not push back rear pistons by C clamp. Instead, you need to turn them to get them back in to get enough clearance for the new pads.

 

Also make sure the little dibit sticking out of the pad's shims lines up with the groove in the piston. Otherwise you'll never get the e-brake cables back on either.

 

Kiyoshi, when you say turn them to get them back in, are you referring to having the rotors actually turned ? They really didn't seem to need that. Plus I don't think turning the rotors would have given enough clearance to then move the caliper back into position. Maybe I just didn't understand.. I did remove the lower caliper bolt (as per something I read online previously) and swung the caliper up and out of the way to change the pads. That's when I realized that it wouldn't go back into place with the new pads.

As for the pad shim, it was definitely lined up. So that didn't seem to be the problem, but definitely something worth mentioning.

Any idea why there are two bleed valves on each side ?...

 

You turn them clockwise to get them to retract. The piston on the caliper is what you turn. You can use a wrench, I used needlenose plyers (Spelling??). The pliers kind of stripped the piston though.

For those who have done this, what else did you use?

 

I don't know why there are two bleed valves, I just bled the one on the outside and it was fine.

 

I did mine last month. I used needle nose pliers too. Done this many times to other Rear disk brakes systems. I think you can buy a tool that does this, but why when needle nose plier works just as good

 

Ok, so you turn the piston counterclockwise... interesting. I've never seen anything like that before and my buddy who was helping, probably hasn't either... I guess that will give me something to work on now. Guys I appreciate the advice. I knew someone on here would know what I did wrong.... Many thanks ! ! !

Keith

 

lol you know how long it took me to figure out they turn instead of push in and out... luckily i knew a guy at autozone and he lent me the tools for free... good luck with that

 

You guys are the best ! LOL The whole thing is kind of funny really. Figured that it HAD to be something simple... Thanks for passing along the knowledge.

 

Going to try changeing pads today thanks for info