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How to test rear brakes

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Old 08-05-2011, 10:57 AM
  #16  
Sysgen
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Originally Posted by Oddjob
What pads are you using on the rear? Why not blues back there too?

By the way - its normal to go thru all of two to three sets of front pads before killing off a set of rears, even w/ a higher pressure rear bias/proportioning valve.
Cause I'm cheap Initial it was to test if this fixed my vibration issue and it did. I might add some in the back but it would not be necessary because with the Hawk blues in the front I had so much brake it was amazing.

I know about the fact that fronts go faster that the rears, on my initial post I say that the rears don't seem to wear at all, I'm not even sure I get brake dust on the wheels.

I'll try to test this weekend.
Old 08-06-2011, 06:13 PM
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Here's what I tried, I jacked up the car and tried to turn the wheel by hand with a friend on the brakes and could not turn the wheel. Same thing with a 3 foot bar, no way to turn the wheel with almost all my weight on the bar.

Then I started the car and tried to put it in 1st and had no problem at all, even with my foot hard on the brakes, the wheel turned freely, even with the engine idle

What the hell does this mean? Can't be the calipers cause both wheels turned freely.

I even tired removing the fuse from the ABS and it did not make any difference. What's left, brake booster? Is it possible the brake booster could be good for the front brakes but not for the rears?
Old 08-06-2011, 08:44 PM
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Originally Posted by Sysgen
What's left, brake booster? Is it possible the brake booster could be good for the front brakes but not for the rears?
No.

I don't know anything about ABS, but I would guess that either it is the problem, your proportioning valve is broken, or you've got air in the lines, somewhere.

Good luck

Last edited by teamking; 08-06-2011 at 09:04 PM.
Old 08-07-2011, 12:46 PM
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951MAN
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Sysgen,

Just stop by the garage for a little pit stop and I will check it out with you. If I remember correctly the previous owner of your car had also some issue with the rear brake something that was probably overlook by his wrencher since the car was used for street only.

I once drove this car on the track (LCMT) back in 2005 and got my first and last spin at corner #4 . My impression was that either I had some kind of brain fart or some brake problem provoke that spin. So thank for your post now I know .
Old 08-07-2011, 01:00 PM
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Thanks Mic, so your first and only spin was in my car I feel honored somehow

That would explain all my spins also

Will revert with my findings
Old 08-13-2011, 06:15 PM
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Ok, changed the brake master, lift the rear of the car and in first gear the car will stall if I press the brake but if I give it a little gas the wheels still turn even though I press hard on the brake. Sometimes only one wheel will turn and the other one is stopped.

With the ABS enabled or disabled doesn't make a difference.

So here's the big question, is this normal? Would someone try this test? Are you able to completely stop both wheels when giving it some gas?

Old 08-14-2011, 11:39 AM
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StyleLab
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Hey Stephane, I could give you hand if you like plus I have a motive power bleeder we could run some blue brake fluid through to see if your calipers are being bled proper.

P.S. We moved back to Montreal and I now have a 2 car garage in my basement!

Nick

Originally Posted by Sysgen
Ok, changed the brake master, lift the rear of the car and in first gear the car will stall if I press the brake but if I give it a little gas the wheels still turn even though I press hard on the brake. Sometimes only one wheel will turn and the other one is stopped.

With the ABS enabled or disabled doesn't make a difference.

So here's the big question, is this normal? Would someone try this test? Are you able to completely stop both wheels when giving it some gas?

Old 08-14-2011, 01:15 PM
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Wow, great news Nick ! Thanks for the offer but I don't think my problem is bleeding. I'm willing to pay a virtual beer to anyone that can try and lift the back of there cars and confirm that they can stop then wheels even when giving it some gas

Is it possible that the engine is strong enough to overcome the breaks???
Old 08-14-2011, 01:43 PM
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Originally Posted by Sysgen

Is it possible that the engine is strong enough to overcome the breaks???
Yes. This is how big smokey burn-outs are done. Hard on the brakes, the fronts are what keep the car in place while the rears are overpowered by the motor.

You apparently don't have LSD which is why one wheel will stop while the other will turn.

Normal.
Old 08-14-2011, 03:41 PM
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Originally Posted by ninefiveone
Yes. This is how big smokey burn-outs are done. Hard on the brakes, the fronts are what keep the car in place while the rears are overpowered by the motor.

You apparently don't have LSD which is why one wheel will stop while the other will turn.

Normal.
That makes a lot of sense, never tried doing that but I can see it, Thanks and indeed I do not have a LSD

I dismantled my old master and found this

First picture you see the locking pin and the hole for the oil. All makes sense, but in picture two you'll see a small disk that was sitting in the bottom, it did not align properly with the hole, and it can't rest flat with the bottom because of the locking pin that sticks out. Anyone knows what the hell is that thing? My replacement MC did not have that.



Old 08-14-2011, 09:14 PM
  #26  
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Does your parking brake work? See if it's more effective at stopping the wheels while accelerating.

I'd expect, if you have the brakes on hard, the engine wouldn't be able to overpower the car.

I know when I've done some boost tests, and I want to build boost pressure, but not exceed the local speed limits, I'll left-foot brake - and I never seem to have a problem keeping the engine at bay (usually in 2nd or 3rd gear.)
Old 08-14-2011, 10:07 PM
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Originally Posted by Van
Does your parking brake work? See if it's more effective at stopping the wheels while accelerating.

I'd expect, if you have the brakes on hard, the engine wouldn't be able to overpower the car.

I know when I've done some boost tests, and I want to build boost pressure, but not exceed the local speed limits, I'll left-foot brake - and I never seem to have a problem keeping the engine at bay (usually in 2nd or 3rd gear.)
My parKing brake works but have not tested it in this scenario but it has happened in the past that while backing out of my driveway that I forgot to remove it and I can still move but you notice quickly that something is wrong.

Different situation here, you are applying the brakes on all four wheels, not just the two rear wheels.
Old 08-15-2011, 12:13 AM
  #28  
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Originally Posted by Sysgen
Different situation here, you are applying the brakes on all four wheels, not just the two rear wheels.
Actually, the parking brake uses shoes applied to the inside of a drum - actuated via a cable. The regular brakes use pads applied to a disk, actuated by hydraulic pressure. If the regular brakes are less efficient than the parking brake against the engine, you have a serious problem.



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