Brake Piston not engaging

[alifeva]

Greetings gentlemen, today I decided to do the brake pads because i was hearing squealing.

Well after this job I put everything back together and I am at the last step where you pump the brakes for the piston to adjust to the right pressure. 20 - 30 slow pumps later my brake pedal still hits the floor. Now I am worried. I still took it for a spin and it will come to a stop but the pedal is hitting the floor. What scares me is when I press the brake pedal in slightly about an inch or two, I hear a clicking noise underneath the passengers floor.

The only thing I did different this time around was instead of removing both bolts on the caliper and laying the caliper on the removed tire but just removing the bottom bolt and twisting the caliper up to get to the pads.

Please someone confirm my fear that the cable is screwed up. I am crossing my fingers that its just the piston is stuck and I need to clamp it all the way down instead of half way.

[Leung]

odd that's the way i do my brakes on any car. i just remove one of the bolts and then flip it upwards. i've never had to remove the whole caliper off of the bracket unless i'm replacing the caliper because it's seized or over extended.

[Fake Thug]

cable? rear brakes? There has to be air in the system. I'm scratching my head trying to figure out how it entered the system. Was the cap off the MC resovoir? did you pump the brakes with the cap off?

[alifeva]

No, master cylinder is about 4 months old, fairly new, cap is on fluid is in. Alls I did was the brake pads and now the pedal touches the floor, piston never re-adjusted. kind of feels like when I had to get my master cylinder replaced, yes thats a good comparison. but everything was working just fine until i put new pads in today. i should of just left the car the way it was. What explains the clicking noise under the passenger floor when pressing the brake pedal softly? I can make it click as many times as I tap the brake pedal about an inch doesn't take a lot of foot and the click click click is fairly loud. E-brake engages and the pedal is firm when the car is powered off. Air in the system? I remember starting the car and letting it warm up before even entering and trying to re adjust the piston.

oh this is the front brakes. I don't have calipers on my rear brakes from what I can see. I wanted to replace the rears as well because I see a brake line going in to the back but I am not sure how! they are hiding. I also said cables because I was under the impression that brakes functioned with cables which is why it is clicking under the floor every time I tap the brakes.

[js593]

clicking under the floor is the Solenoid, thats normal, it does however sound like your Master cylinder. I would try and bleed the system and make sure there is no air in it.

Letting the car warm up to do brakes is useless. Brakes is a friction thing, not a heated brake line.

[alifeva]

I warmed the car because I do that every time before I drive, I let the idle drop. I am just trying to trace my steps so you guys can get an idea of what went wrong. The MC was just replaced , and the main thing is that it was working fine and better before I replaced the pads today. Tomorrow I am going to compress the brake pistons again, this time all the way instead of half way with the C-Clamp and try to adjust it once more, if it doesnt work Ill take it in to my mechanic and we will find out the culprit. But I think you are right, definitely feels like when my MC was not working a few months back.

[alifeva]

hey I just got off the phone with my mechanic, I am going to bring it in tomorrow to find out what I did wrong. He said the same thing, He said "are you sure you didn't mess with any hoses you don't know of and or let the caliper hang because I did your master cylinder recently if you remember" I told him "alls I did was the brake pads and the only difference I did was instead of taking the two bolts off and resting the caliper, I took the bottom one only and twisted it upwards to get to the pads." So hes gonna take a look see what I managed to mess up. I will get back to you guys tomorrow afternoon. Thanks for the quick responses gentlemen.

[Losiracer2]

you sure you put in the clips that the pads slide on correctly? and is everything lubed up properly w/ grease? ie: slide pins and those clips?

[alifeva]

actually interesting that you mentioned that! I discovered I have an extra shim clip on the pad when I removed them. 2 are the same and the other 2 match but 1 is different. I actually put it over another shim thinking thats how it was the whole time. So my left pad on the inner pad (the one touching the brake piston) is doubled up. Maybe that is the culprit!!!! I will remove all shims tomorrow and take a picture you guys tell me why I have an extra shim. Thanks Loisracer you are very wise !

[js593]

Shims will not matter that much, they are basically protectors for the backing plate of the pads. Or more refered to as spacers.

[Losiracer2]

Shims will not matter that much, they are basically protectors for the backing plate of the pads. Or more refered to as spacers.

well once, on my EBC greenstuff pads, the shim shifted off the pad and was kinda making the pad sit at a weird position.

But lol, I wasn't really thinking about THOSE shims, haha, I was thinking about those clips that the ears of the pad slide on, idk if thats the proper term for them, but the shiny metal pieces that clip onto the caliper and caliper bracket...is what i was talking about.

BUT if you solved your problem then YEEYYYYY!

[Losiracer2]

also try putting this CRC brake quiet stuff on the back of the pads before you install them, it helps quiet down squeeling and makes the shim stick to the pad. Its this red gooey stuff you can buy at autozone for like 5 bucks. Helps a lot.

[alifeva]

Shims will not matter that much, they are basically protectors for the backing plate of the pads. Or more refered to as spacers.

that what i was thinking when i doubled em up lol, thought it might help the squeal because the one underneath was almost copper and the piston mark was engraved in it.

also try putting this CRC brake quiet stuff on the back of the pads before you install them, it helps quiet down squeeling and makes the shim stick to the pad. Its this red gooey stuff you can buy at autozone for like 5 bucks. Helps a lot.

really, i have never used it and i think i might have a 2 little capsules in my shed just didnt know how to apply it. so i put the brake quiet on the back of the pad then click the shim over it? or on the back of the shim?

[js593]

That stuff is intended for the back of the pad, NOT the portion that contacts the rotor. Ive seen that shit cause some really bad damage when put on the rotor/portion of the pad that contacts the rotor. it just makes the pad stick to the caliper when the piston retracts, so you dont get a squealing noise.

[jdmjunky]

virginia tech all the way!!!