Caliper touching rotor

VII · 06-11-2009, 08:01 PM

Hiya. Cleaning things up, making them less ugly. A little paint for my front caliper buddies and after I put everything back together and mounted them I noticed that the floating caliper portion is touching the rotor and not allowing it to turn. I am able to move the floating portion sorta up-ish and there are no touching issues but the mounted caliper portion has a U spring thing on it that pushed on the caliper which is attached to the floating portion so it just pushes it against the rotor again. I tried to bend the U spring thing a little but it has a lot of force. I could bend it more but I'm sure I need it there to stabalize everything. Has anyone else had this problem? Ideas on fixing it? The rotor is mounted nice and straight, no issues there.

Touching.

Not touching when the floating portion is pulled up-ish. This is where it should be but the spring thing pushes it back down against the rotor.

SuperXRAY · 06-11-2009, 08:43 PM

VII,

Did you pay close attention to how the spring was when you disassembled the caliper sets? I had the same issue when I reassembled mine after painting, but I noticed that I had actually forgotten the springs.. I wondered why they were such a pain to install until I put them on the right way. There should be significant pressure pushing the caliper outwards (or up, away from the rotor, etc.) where the spring contacts the bracket. Also, if I remember correctly, they can be installed swapped (left wheel to right wheel) and will make a difference on the force it applies.

Just a question here...where your piston housings easily removed? When I reinstalled mine, I naturally had to file away the caliper paint on the slide contact area, but I also had to file about 0.002" from the bracket to even come close to being able to get the piston housing back in there.

SuperXRAY · 06-11-2009, 08:48 PM

Going back and rereading...can you take a pic of the inside portion of the caliper assembly? Sounds your springs are on inside-out, if that makes sense.

It looks like you replaced the dust boot...good call.

Remember to get some nice (it's expensive too) squeal treatment. I use some CRC stuff that works excellent, but it does take about 15 minutes to dry. Alot of people use the 3M Caliper Grease with the dauber brush. Also, don't forget to align those pistons properly so your pads wear properly. It looks like they are already.

944 Ecology · 06-11-2009, 11:32 PM

When you install the pads, the frame will no longer touch the rotor.

VII · 06-11-2009, 11:58 PM

Thanks for the replies. I never removed the "spring" when painting. I gave them a tug and realized it would take much more effort than I was willing to put in to take them out so I just left them in and painted since they're not really noticeable anyway. The only thing I can think of is that when reinstalling I bent the spring more so that even more pressure is applied but it seems to be about the same resistance as when I was taking them off and cleaning.

The piston housing was not easily removed. I even broke a tab off when trying to remove the passenger side with a rubber mallet. I quickly found out that I had to remove all of the paint and some of the metal so that I could get them in. I fought with them for a while before I gave up and pulled out the rotary tool.

I'll try to take a picture tomorrow or the next day, but first I'll try putting just the pads on like ecology suggested. I actually didnt replace anything. I should have removed the piston and cleaned it all up while I was there but I'm too busy to do that now. The brakes function perfectly now anyway so I'm sure they're ok. The piston seal has some slight cracking coming about but for now I just lubed it up and maybe I'll apply a thin coat of rubberized spray stuff.

A couple hours ago I picked up some stop squal blue goo. Nothing fancy, I've used it a handful of times before with good results. Maybe I'll look into something else if the 944 is different than the other machines I've messed with.

How do I go about aligning the piston correctly? I noticed it has a raised portion to it. The piston is in the same orientation it was in when removed so perhaps I'll be ok?

Thanks for the help

BeerBurner · 06-12-2009, 05:18 AM

944 ecology is correct. Installing the pads will make everything right.

I'll be honest, I confuse myself every now and then with that. After pulling the pads I notice that things are rubbing and then I realize "Yeah... gotta put them back in."

BB.

SuperXRAY · 06-12-2009, 06:59 AM

Most of the piston face is raised. The low portion, or dado, goes to the leading edge of the pad. That is, if you view the left front wheel like a compass, where north was straight up, the dado would point towards South-East. On a clock, it would be like 4:30'ish. The important thing is that it aligns with the pad properly.

The point of that dado is to keep the pad wearing properly and provide full pad contact with the rotor under driving conditions and heavy breaking.

I don't know about everyone else, obviously they have different experiences with their calipers. Mine only touched until the spring was installed correctly, but to each their own.

VII · 06-12-2009, 10:05 AM

I went ahead and put the pads on the drivers side and everything worked out just fine. Thanks for the help fellas :0)