brake problems..already

keVIIIn

Dedicated LVC Member
Joined
Nov 9, 2011
Messages
2,432
Reaction score
118
Location
Chi
As some of you know I converted to mustang hubs and put cobra front cobra brakes on my car..well I'm having some issues with the brakes now, I don't believe it has anything to do with the front brakes though, I think it is the rears that are giving me issues.

To start with, when I pulled apart the rears to redrill my hubs I noticed the pads in the rear were getting pretty thin, so I figured since I have them apart I might as well buy some new brake pads. So I redrilled the hubs, installed the new wheel studs and reassembled everything including new pads, and of course since I installed new pads I had to push the piston back in the caliper. Now I had heard the rears require a special tool to push the piston back which I did not have, but I knew they are supposed to turn instead of just pushing them in, so I was able to grab the piston with a pair of channel locks and manually turn them which I did. Pistons went in without issue on both sides. Put everything back together and pulled the car out of the garage to turn it around the other way so I could start on the front hubs. Well when I pulled it out I noticed the pedal felt very soft even after pumping the brakes a few times. I drove it up and down the driveway a few times and it felt like it had no braking power..it took alot more effort to stop the car than ever before. Mind you I never had this problem before all of this.

Well I knew I was going to bleed the brakes anyway since I was swapping to cobra brakes up front and figured maybe some air got it and made the pedal soft. So I completed the rest, swapped front hubs and assembled cobra brakes, bled the piss out of them and made sure there were no leaks at the banjo fitting. Then moved to the rears and bled the rears to make sure...no air bubbles at all.

Finished everything last night and pulled it outside and still the pedal felt soft and the brakes felt weak, felt exactly the same as before. I said enough is enough for one day and put it back in the garage hoping to sort it out today. Well today I pull the car out again and still, same issue. I pulled it up and down the driveway and went around the block with it a few times and the brakes are horribly weak. I played with the emergency brake thinking maybe it wasn't allowing the pads to make contact fully..and found that the rear brakes can barely hold the car back idling in drive when the e-brake is pulled. It is like I have barely any rear brakes at all.

Is there something I did wrong when reassembling the rear brakes or pushing the piston back into the caliper? Anyone have this issue before when doing a brake job on the rear brakes? Any thoughts or help is appreciated. thanks!
 
As some of you know I converted to mustang hubs and put cobra front cobra brakes on my car..well I'm having some issues with the brakes now, I don't believe it has anything to do with the front brakes though, I think it is the rears that are giving me issues.

To start with, when I pulled apart the rears to redrill my hubs I noticed the pads in the rear were getting pretty thin, so I figured since I have them apart I might as well buy some new brake pads. So I redrilled the hubs, installed the new wheel studs and reassembled everything including new pads, and of course since I installed new pads I had to push the piston back in the caliper. Now I had heard the rears require a special tool to push the piston back which I did not have, but I knew they are supposed to turn instead of just pushing them in, so I was able to grab the piston with a pair of channel locks and manually turn them which I did. Pistons went in without issue on both sides. Put everything back together and pulled the car out of the garage to turn it around the other way so I could start on the front hubs. Well when I pulled it out I noticed the pedal felt very soft even after pumping the brakes a few times. I drove it up and down the driveway a few times and it felt like it had no braking power..it took alot more effort to stop the car than ever before. Mind you I never had this problem before all of this.

Well I knew I was going to bleed the brakes anyway since I was swapping to cobra brakes up front and figured maybe some air got it and made the pedal soft. So I completed the rest, swapped front hubs and assembled cobra brakes, bled the piss out of them and made sure there were no leaks at the banjo fitting. Then moved to the rears and bled the rears to make sure...no air bubbles at all.

Finished everything last night and pulled it outside and still the pedal felt soft and the brakes felt weak, felt exactly the same as before. I said enough is enough for one day and put it back in the garage hoping to sort it out today. Well today I pull the car out again and still, same issue. I pulled it up and down the driveway and went around the block with it a few times and the brakes are horribly weak. I played with the emergency brake thinking maybe it wasn't allowing the pads to make contact fully..and found that the rear brakes can barely hold the car back idling in drive when the e-brake is pulled. It is like I have barely any rear brakes at all.

Is there something I did wrong when reassembling the rear brakes or pushing the piston back into the caliper? Anyone have this issue before when doing a brake job on the rear brakes? Any thoughts or help is appreciated. thanks!



Are the calipers even engaging in the back? Maybe there locked up now? I know when one of mine over extended I replaced the whole thing.
 
Do your new rear pads have little "nipples" on the steel part of the pads where the caliper piston meets pads? The caliper piston "cutouts" have to be at 12 and 6 oclock for pad nipples to "lock" inside caliper piston.
 
The sliding pins are good..I pulled them out and regreased them, the pads are installed properly and the piston is in the proper position on both sides (12 and 6). Evan now that I think of it, I started retracting the piston on one side and forgot the other side caliper was just hanging free with no rotor between the pads so I extended that piston slightly..but not by much. I didn't open any bleeders on the rear brakes when I retracted the pistons. The only time I opened the rear bleeders is when I bled them after it was all assembled..I did it the two person way with one in the car holding pressure on the pedal while cracking the bleeder and shutting it while still holding pressure on the brake pedal. Bled both rears enough to flush all old fluid from the calipers while adding new dot 3..never let the master drain either.

So there shouldn't be any air what so ever in the system..I'm thinking that I may have f'd up the one caliper by extending the piston by accident. Evan what happened with yours when you did this? Or did you just replace it right away?
 
I read in the manual to bleed the brakes in a certain order; RR-LR- RF-LF. First time I did rear brakes, I found the right size pipe, and made a spanner wrench out of it, cutting off what I didn't need, leaving two prongs. Works good.
 
My dad brought up a good point, told me to check at the back of the master where it bolts to the brake booster and check for wetness. When we were pushing the rear pistons in I didn't open any bleeders but forgot to take the cap off the master so when we were done I noticed some brake fluid on the floor under where the master would be and I figured it just came out the cap.

I checked the back of the master and there appears to be some wetness under where it mounts to the booster..but its tough to tell since it was two weeks ago that I was messing with the rear brakes. I'm thinking maybe I blew the seal at the master? Or maybe messed up the master cylinder somehow? Any thoughts on this?
 
Try using a bleeder jar. I use a baby food jar. Drill hole in top, feed hose thru hole then electric tape on hose below cap so tube cannot pull out of cap. Tape hose so hose is 1/4 off bottom of jar. Start in RR and use the jar with hose hooked up to bleeder. I like to put 1/2 inch of clean new fluid in jar to start. I know i know people have bleed amillion brakes with out it. I have some cars that needed it to get air out. My mk8's where one of them.
 
I think you answered your own question when you said you didn't remove the cap from the reservoir when you retracted the rear pistons.
 
... set the parking brake a few times.

When installing new pads, machine or replace rotors. Not a good idea to slap fresh pads on glazed rotors
 
... set the parking brake a few times.

When installing new pads, machine or replace rotors. Not a good idea to slap fresh pads on glazed rotors

True about the pads, I wouldn't on the fronts but figured I could get away with it on rears. I set the parking brake a few times trying to figure out why I had no braking power. I set it and released it once, then the second time I couldn't get it to set the pedal kept coming back up..played with it a few times and then I was able to set and release it..did it a few more times to ensure it wasn't hanging up..BUT something isn't right with the rear brakes since when I set the parking brake the car will easily roll while in drive and idling. And like I said on top of that when braking the pedal has too much travel before the pads makes contact with the rotor. I'm not quite sure what's going on..I'm thinking it might be a combinstion of the rear piston(s) being stuck and something wrong with the master.. since I found some mystery brake fluid under where the master is after I pushed the rear pistons in. (I now know this was a bad idea to do without opening a bleeder).

I was thinkin about giving you a buzz and telling you what's its doing..hard to explain on the internet. I hear you're the "brake guru" lol.
 
Can ya pop the rear wheels off and msg me a couple pics of the calipers? I got a new cell # because a certain LVCer wouldn't quit calling me nonstop, I'll pm ya my new one
 
Have you had someone press E brake while you watched BOTH calipers to see if cables move free?
 
No I haven't had a chance to do anything with it, I'm working the next three days so I won't be home till friday. Sapp ill take a few pics Friday for ya. Thanks.
 
Just a couple of things. The tool for that cost me $18 at Lordco, a local franchise. I was surprised.

I bought a pressure bleeder and I ain't never going back to the old ways. Just put 15lbs on the system, Lincoln is fine with quite a bit more, and you can individually bleed not only bleeders, but fittings and any joint in the system. It will show you any leaks you might have under pressure, which you really cant see any other way, without some friend leaning on the pedal. Recommended.
 
My dad has a pressure bleeder at home..gotta see if it will work on my car. Surely will make life a bit easier.
 
Fixed the problem yesterday. Turned out to be a bad pass rear caliper. The piston kept retracting too far so it would take a lot of pedal travel before the piston made contact with the pad and rotor. Put in a rebuilt caliper and bled the rear brakes again in the proper order and no more problems. Unfortunstely wasn't able to drive it at all besides up and down the driveway due to the pure salt water covering the streets..this winter can't end any faster.

Waiting for a nice warm(er) day to get it outside, clean it up and get some good pictures...but for now this is all I got.

20131214_172520_zps0aef9d9d.jpg


20131214_172804_zpseeefbc91.jpg


20131215_153611_zpsf2f66868.jpg


20131215_153624_zpse30bc0a3.jpg


20131215_153636_zpsaec1c919.jpg
 

Members online

No members online now.
Back
Top