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Brakes won't lock up

XuperXero

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#1
As title says, brakes currently won't lock up from full pedal force as if the brakes are lacking clamping force. I've recently installed Goodridge SS lines and EBC yellow pads on the front. Used all 500mL of OEM Ford DOT4 brake fluid during bleeding to make sure not a single drop of old fluid was left.

Just took my car to track last Friday and the first thing I noticed was that I couldn't lock up the brakes no matter how hard I tried even with crappy Nexen tires. After the track day, I've tested again on the streets. It's conclusive that the brakes won't lock up. Any suggestions or ideas?

The only thing I can think of is that the Goodridge SS lines is much longer than stock, but fluid should always be pressurized so this shouldn't have any affects right?
 


D1JL

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Although I cannot speak for a China market car but I hope you realize that this car is equipped with an anti-lock braking system and they are not suppose to lock.

So let's just confirm a few things.

Did you open the bleed valve when pushing the pistons back in and not push dirty fluid back into the master?
Did you completely remove both front calipers from the car and possibility put them back on the wrong sides?
Did you use a force bleeding system or do it manually?
If you did it manually, did you start and have the car running during the last bleed?
After the rear caliper pistons are reseated they need to be readjusted by operating the E-Brake handle several times.



Dave
 


OP
XuperXero

XuperXero

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Thread Starter #3
Although I cannot speak for a China market car but I hope you realize that this car is equipped with an anti-lock braking system and they are not suppose to lock.

So let's just confirm a few things.

Did you open the bleed valve when pushing the pistons back in and not push dirty fluid back into the master?
Did you completely remove both front calipers from the car and possibility put them back on the wrong sides?
Did you use a force bleeding system or do it manually?
If you did it manually, did you start and have the car running during the last bleed?
After the rear caliper pistons are reseated they need to be readjusted by operating the E-Brake handle several times.



Dave
Hi Dave,

I do realize the car is equipped with ABS, what I meant is forcing the ABS to kick on which means the tires are locking up and I have full braking power. But at the moment, it's not kicking on, and even if ABS failed, the wheels aren't locking up.

The bleed valve was closed when piston was pushed in. I've done brake pad swaps many times and this is the first I've heard of pushing the dirty fluid back in Master... I always thought bleeding it would remove all the old fluid.
Calipers were completely removed, nipples facing upwards so I'm sure it's not the wrong direction.
Manual bleed with pumping like every other car starting from the furthest away from reservoir and moving up to closest. RR, LR, FR, FL.
Car was not running (Although I did see this in mentioned when searching in other threads), is this important? Seems like it's not necessary.
Rear pads was done earlier and not at the same time as the front pads. I only changed front pads and SS lines this time.

What's also strange is that when I was on track, I could use the same braking reference points to enter the corner without any issues. It just that if some idiot cuts in front of me, the brakes never locked with current brake setup. But it did with the OEM's.
 


D1JL

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Please don't misunderstand, I was not inferring that you didn't know what you were doing.
I was just trying to think of things that would not make the brakes work.

As for opening the bleeder valve when pushing the pistons back is so as not to screw up the valves in some ABS systems (maybe not this one).
However, it is a good habit to get into.
Running the car when bleeding is also a good thing also to make sure all the valves work correctly.

Well if the problem is not in the hydraulics then it must be mechanical.
Did you just swap the pads or did you also machine/replace the rotors?
If you just swapped the pads, then it may take a few extra miles to get the pads to re-seat (I have done this myself many times).

The only other thing is the pads themselves.
I assume that you didn't get any chemicals on them.
So that leaves, did you brake them in slowly so as not to heat glaze them?

I think we have covered everything?
The last thing you can try would to put the old pads back in to see if then the system works correctly.
This should also prove if your hydraulics are all correct.




Dave
 


LilPartyBox

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#5
I haven't worked with our brakes yet but on VWs, if, during bleeding, you let the brake fluid drop below a certain level you'd have to bleed the ABS module separately. I went out and bought a motive power bleeder for that reason. It adds fluid as you remove it so there's no danger of levels dropping too low.
 


OP
XuperXero

XuperXero

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Thread Starter #6
Please don't misunderstand, I was not inferring that you didn't know what you were doing.
I was just trying to think of things that would not make the brakes work.

As for opening the bleeder valve when pushing the pistons back is so as not to screw up the valves in some ABS systems (maybe not this one).
However, it is a good habit to get into.
Running the car when bleeding is also a good thing also to make sure all the valves work correctly.

Well if the problem is not in the hydraulics then it must be mechanical.
Did you just swap the pads or did you also machine/replace the rotors?
If you just swapped the pads, then it may take a few extra miles to get the pads to re-seat (I have done this myself many times).

The only other thing is the pads themselves.
I assume that you didn't get any chemicals on them.
So that leaves, did you brake them in slowly so as not to heat glaze them?

I think we have covered everything?
The last thing you can try would to put the old pads back in to see if then the system works correctly.
This should also prove if your hydraulics are all correct.




Dave
I'll keep in mind of the bleeding habit, in fact, I may try to bleed it again using your methods this week. I'm certainly not comfortable with the idea that my brakes are not at full braking power.

The rotors are brand new OEM blank. I had the pads and rotors replaced together. They were gently broken in as per EBC's instruction to drive gently for the first 500km. After that, I put about 2000km of normal street driving, not a lot of sudden braking or hard braking before the track day.

Getting my old pads on could be a problem.... [biggrin]

 


D1JL

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OK, don't put the old pads back on. LOL

My last thought is; did you wash the new rotors before use as they normally come coated in an oil.

When you inspect everything again, you might try taking the surface off the pads with sandpaper.



Dave
 


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XuperXero

XuperXero

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Thread Starter #8
OK, don't put the old pads back on. LOL

My last thought is; did you wash the new rotors before use as they normally come coated in an oil.

When you inspect everything again, you might try taking the surface off the pads with sandpaper.



Dave
I'm aware of the anti-corrosion oil on it, that's why I flooded it with brake cleaner before putting them on. But I'll sand the pads like you said when I do bleed them again.

If after everything said in this thread fails... I'm tempted to swap pads back to OEM to see the difference, but with dealer mark up, that drive's me away from OEM. Dilemma...

Thanks for the input so far Dave.
 


D1JL

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#9
The only thing left is the pads.
Personally I only use OEM pads.
Maybe you could try another (cheap) brand just to see if there is any difference.

Good luck.



Dave
 




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