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So yesterday I spent a lot of time changing my brake pads and rotors.

Now I'm having a bunch of issues...

First off the brake has a zinc coating on it. I just went around the block for testing and the coating has not disappeared totally yet. I'm sure it will... But because of those the issues I'm concerned about doing anything further before I get some input from my fellow SwedeSpeeders...

I should also mentioned the brakes still feel strong when the car is stopped, not running, and I press on the brake pedal. In other words the brake pedal stiffens as I apply a few pushes.

1. First off I lost what it seems to me a lot of grip from the rear emergency brake. If it's just the cable to adjust I will need to find how to do that. If it's something else I hope some one has some ideas :)


2. Secondly just going around the block the brakes feel very mushy. It's possible that the coating on the new rotors plus the new brake pads need setting for that to go away. but with the emergency brake issue in mind I'm concerned. I may be over reacting because it's the first time I've done this and I don't want to take any chances...

I know many will ask: "Have you bled the brakes?". No I have not. I want to do so but I don't have what is needed on hand at the moment. I thought that bleeding brake lines was not entirely necessary for brake pad change. You tell me if I'm totally wrong and if it is essential to do so because it is always the procedure to change pads...


3. I have this metal noise like the rotor is spinning on the guard. I think it is only on the front left where I have Hawks pads (akebono on the rear) but because the new pads and rotors make a lot of wear noise (which I assume is normal at first) I'm not sure it is only there. I'm going to check that out right away while waiting for some response. If not that what could it be?


I appreciate everyone's input on the matter...
I feel kind of down with the whole thing... :(
 

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1) The emergency brake is somewhat self-adjusting. After changing the pads I believe you're supposed to give it three hard pulls (pull, reset, pull, reset, pull, reset) in rapid succession to adjust the pistons. If the cable is still loose after that, it will need further manual adjustment using the adjustment screw on the parking brake handle.

2) Yes you have to bleed your brakes. It isn't the new rotors. When you press the pistons back into the caliper to put the new pads in, you most likely introduced air into the lines. At any rate, you should always replace your brake fluid when you replace pads/rotors.

3) Some noise is normal when you put new brake pads on. However, a constant rubbing sound could be something like the piston not being fully retracted before installing the pads (which caused the pads to come in constant contact with the rotors). Or like you said, the dust shield is contacting the rotor or there could be a stone wedged between the dust shield and the rotor. I would lift that wheel off the ground and spin the wheel by hand to investigate where the sound if coming from.
 

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Check the side where the zinc coating hasn't completely worn out first. It should disappear as soon as the brakes are used so something is amiss. Disassemble the brake and check to see if the piston has seized and if the pads are installed correctly. Also use brake grease on the moving parts. Did you retract the pistons properly?

The metal noise may just be the shield rubbing on the rotor.
 

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Discussion Starter · #4 · (Edited)
Check the side where the zinc coating hasn't completely worn out first. It should disappear as soon as the brakes are used so something is amiss. Disassemble the brake and check to see if the piston has seized and if the pads are installed correctly. Also use brake grease on the moving parts. Did you retract the pistons properly?

The metal noise may just be the shield rubbing on the rotor.
Yes #3 is solved. When I installed my front trust I must have bent the shield. It's not touching now... I'll have to check them all.

I did not apply much force when I first went around the block especially after hearing that metal sound.
The coating is almost gone. Should I try again and see how it brakes?


Oh and btw way, after installing the rear I realised I had forgotten to put the greas. I had a lot to do so I did not redo them. I did apply it to the front. How critical is the grease?
I was not sure where to apply it either :( On the front I put it a little bit where to piston is in contact with the pad and where the second pad is in contact with the caliper as well as around the pads hooks (obviously not on the pad itself :p)

I think the piston are fine...
 

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Discussion Starter · #6 ·
Try again, but the mushy feel isn't right. If it still feels mushy, you must bleed the lines, when everything else checks out ok.
I'm putting the wheel back on for an other try...
 

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Discussion Starter · #8 · (Edited)
I'm putting the wheel back on for an other try...
Okay, I'm back and It's much better...
No noise from the shield has expected :D

Now it's hard to tell for sure whether it's working properly or not because . . . you know how it is when you do something you're no use to do, you become hyper sensitive and question everything that is happening with hesitations . . .
What I can tell is that it working well enough to drive wish is better than when I first thought it would be. In other world it's not really mushy... Is it braking better maybe not quite yet as the pads are new and I guess thing are not bedded yet.

It's also noisier when I brake which I think means more grip or more friction.
Once I pulled back in the drive way their seems to be a smell which I think is normal too (?) and brakes were generating heat. More than usual? I don't know...


Based on that second test I feel a little bit better. As you implied, alddbaran, it's possible that it had to do with the piston. My emergency brake seems to be working better too though I noticed I need to pull on it a little further than usual.

I'm going to keep it slow for the next few days keeping my distance with everyone just in case.

I probably will have to take all the wheels of again to make sure bolts are tight. I did not have torque specs so I don't know how much is required for the hanger bolts and caliper clamp slider screw. If any one has those that would be great!

I will look into bleeding the brake soon...
 

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Discussion Starter · #9 ·
ok, good luck.
Grease should also be applied to the sliding caliper pins. Any moving part that doesn't rely on friction of two surfaces to function need some grease.
Ah! thanks. I did not do that... Man, I'd hate having to redo everything!!! :(
 

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have you made sure the splash shield didnt get bent into the rotor? a small push will push it back out no big deal, also the noise may go away after some time with the pads bedding into the rotors, and grip should return as well.

as far as the zinc coating, it will fade in time, not right away. especially the rears. my ebc rotors still have a goldish hue to them on front (15-20k miles on it) and the rears are still very present (1500k)
 

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Discussion Starter · #11 · (Edited)
have you made sure the splash shield didnt get bent into the rotor?
Yes that is taken care of. It's good it did not bent into the rotor while it was touching... the lower inside edge of the rotor was touching the shield side wall. Not the 90° tab.


also the noise may go away after some time with the pads bedding into the rotors, and grip should return as well.
as far as the zinc coating, it will fade in time, not right away. especially the rears. my ebc rotors still have a goldish hue to them on front (15-20k miles on it) and the rears are still very present (1500k)
That does reassure me :p Thanks!
 

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Discussion Starter · #13 ·
Forgot to mention this. After retracting the pistons when you install the new pads, you are supposed to give the brake pedal a few firm pushes to get the pistons back out again in contact with the pads.
Actually I instinctively did that though they were not "firm" pushes...
 

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Discussion Starter · #14 ·
And stupid me I misspelled brakes in the main thread title... :facepalm:
 

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Discussion Starter · #16 ·
Lol, I sent an PM earlier to the moderator Chris to see if there are means to make correction. We'll see. Maybe it's something upon which they can improve :p
 

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Discussion Starter · #17 · (Edited)
A couple of important questions...

So I went on a longer drive 15/20min . . . It's braking no question so that is a good thing!
However I need some serious advice to do this better!

1. As I drove and came to lights and stops slowly the brakes would make that light wistle sound I hate. I partially lubricated the front (Hawk HPS) and forgot to lubricate the rear (akebono) before everything was put back together :facepalm:
I'm not sure where the sound is coming from though...

A couple of streets before I pulled in the driveway it stopped, so I'm also not sure if it will go away or not in the coming days (I will monitor it)...

Q: Can someone tells me how to lubricate the brakes! I could not find much on this specific subject on SS.
Where do you put the lubricant exactly? And how much? Pictures would be really helpful. no one seems to ever talk about this



2. I had a slight vibration in the steering wheel when braking slowly, not at speed or at a light, more so in mid range braking situation. Possibly going down hill but I'm not sure about that. An other thing to worry about :(... Now keep in mind I installed front struts at the same time and the car does pull to the right so I need an alignment I know that...

Q: Can the alignment cause vibration on braking? Or should I worry about the brakes? If so what is it I should be looking for? I do my wheels with a torque wrench, cross bold, progressive tightening, so over tightening should not be the issue...


3. I did a stop half way through and once I was home. The brake seemed hotter than I remembered. There is also a smell which I'm guessing is normal with new equipment cooking.

Q: How normal is it for brakes to heat on a new install?


4. I did not have the brake bolt torque specification. I'm not sure where I stand
Q: Can someone tells me what is the torque specification for: front and rear hanger bolts (two different size) and for the brake caliper sliding screws?


I really could use some clarity in this so much thanks for your help!

Greg
 

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To answer Questions 1 and 4:

I lubricated the entire back surface of the pads, the notches where the pads would contact the caliper holder, and the piston boot (after cleaning it). As for how much, well I made sure there was a nice coat, not too thick, but more than just wetting the surface.

I found that the caliper pins should be tightened to 30 Nm (22 ft. lbs). Not sure about the hanger bolts, but those would be higher for sure.
 

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Regarding the brake bleeding:

There is no need to do bleeding, if you don't get air in the system. Pushing the pistons in the calipers back will not cause any air to enter the system. So there is no need to bleed the system. If you change the brake pipes/lines, then yes, as you have opened the brake lines as a system, but an enclosed system can't get air in it unless you do something REALLY REALLY REALLY wrong.
 

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Greg,
get the alignment done and see if it helps with the vibration. Are you also feeling it in the pedals or just the steering wheel?

As far as the brakes overheating I can't say that it's normal. When I changed my pads and rotors at the same time, I did not notice any smell nor my brakes heating up nor strange noises.

Honestly the only thing I can see anyone messing up is installing the pads. Everything else is very straight forward.
Can you describe the pads, the ones resting against the piston. Some have the clips, some have the wires.



Make sure the wires hook onto the indentations at the very edge of the pistons.
 
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