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View Full Version : I probably f*cked up my brakes.



Yuikio
12-02-2005, 09:14 PM
Had to replace the driver's side rear caliper, and both rear rotors and pads. Got everything on and torqued down, and went to bleed the brakes using the ghetto "pump pedal carefully and check if fluid comes out" method. This worked fine for me before, but this time, the system refuses to pressurize. I added new fluid well over the top of the line to the brake system, I didn't even come close to the floor when pumping the pedal, and the bleeder hose was well submerged in fluid. I pumped the pedal for like 10 minutes but it never got normal. Not even a hint of firm-ness. This sounds like what would happen if I got air in the system, but I pumped the pedal for a long time. Seems like the air would have gotten pushed out, but I don't know.

What could I have broken or overlooked? I STFA and the tech section on AW but I still don't know.

[az]

offroader1006
12-02-2005, 09:19 PM
all you did was replace the one caliper along with rotors/pads?

how much fluid did you get out of the system?

nramsey
12-02-2005, 09:26 PM
You mean the pedal never got firm while you had the bleeder valve open? If so, that's normal. You don't build any pressure until the system is all closed up with full fluid and no air in the lines.

If you mean something else can you provide some more details? Were you using a one person brake bleeder kit or anything? It's nearly impossible to bleed brakes yourself without using Speedbleeders or some type of single person bleeding kit.

Yuikio
12-02-2005, 09:46 PM
Hmm. During the install I let about 6 oz out of the system into a milk jug, but when I was trying to bleed, I never got anything to come out. All I did was replace the caliper and rotors/pads on the rear.

nramsey, I thought that too, but then I tightened the bleeder valve back up and screwed the cap back on the MC to build pressure, but that didn't work either. The pedal never got firm at all. I've bled the brakes this way before, wihtout a pressure bleeder, just pushing the pedal down halfway until fluid comes out the caliper, but this time it just didn't work. I'm wondering what I could have possibly messed up. All the lines are tight, no leaks, the fluid level is fine, and it seems like I pumped enough to get any air bubbles out of the system, but no dice.

I wasn't trying to bleed out of the caliper I installed, it was the other side that never had any problems.

bitterchild
12-02-2005, 09:53 PM
6oz is a lot of brake fluid. like 20% of the system.

I don't get it. you've got everything closed and you're wondering why you can't puit the pedal to the floor?

or it's just spongy?

i don't see you mention a proper bleeding procedure anywhere.

Yuikio
12-02-2005, 10:02 PM
Everything is closed, but when I pump the pedal to squeeze fluid out of the system there's no pressure in the system. The pedal is worse than spongy; it feels like it's barely doing anything.

I followed the ghetto bleeding instructions on AW, which are connect a hose to the bleeder screw, submerge hose in a little brake fluid to make sure it doesn't suck in any air when pumping the pedal, and make sure you don't squeeze out too much fluid from the MC. It worked great last time. It's not a power bleeder, but it should work, I think.

No fluid is coming out of the caliper. I never said that before.

turbojunkie
12-02-2005, 10:13 PM
You need to pump the pedal while the bleeder is closed, then hold the pedal down, then with the pedal held down open the bleeder until the fluid stops flowing, then close the bleeder, then repeat until all air bubbles are gone.

turbojunkie
12-02-2005, 10:14 PM
^^^ forgot to mention.......you need 2 people.

trailboss
12-02-2005, 10:47 PM
i had to bleed the abs system cause the pedal wouldn't get firm and there was air in there. It also helps if there is two people.

DRA4
12-03-2005, 12:02 AM
Next time, bring your girlfriend to press the pedal.

nramsey
12-03-2005, 12:17 AM
Or get some of these...work great.

http://www.speedbleeder.com/

Mawhitey
12-03-2005, 05:16 AM
Not to scare you, but this method can cause the Master Cylinder to fail, pushing the piston past it's normal travel and allowing the seals to catch on the rougher, unused part of the master cylinder walls.
This makes the seals flip, and therefore fail to pressureize. I am sorry to scaremonger, but this i have had this a few times in the past, hence i only use an air pressurized bleeder now

Yuikio
12-03-2005, 10:28 AM
^^I've read that too. I should probably just try a power bleeder or something similar.

Yuikio
12-03-2005, 03:25 PM
OK, for those of you that were wondering (nobody, but humor me for posterity)

There was an air bubble in the new caliper, since it had never had fluid sent through it. Put the bleeder hose and stuff on there, and it worked perfectly.

I ran out of brake fluid ,though, and I was going to bleed my clutch since it's been squeaking because of the SuperBlue. So JustBrakes/Greasemonkey, here I come.

Neo1130
12-03-2005, 03:36 PM
Originally posted by Yuikio
OK, for those of you that were wondering (nobody, but humor me for posterity)

There was an air bubble in the new caliper, since it had never had fluid sent through it. Put the bleeder hose and stuff on there, and it worked perfectly.

I ran out of brake fluid ,though, and I was going to bleed my clutch since it's been squeaking because of the SuperBlue. So JustBrakes/Greasemonkey, here I come.

Super blue makes your clutch squeek? How so?

Yuikio
12-03-2005, 06:20 PM
Well, the hydraulic clutch uses the same fluid as the brakes, and I guess the dye that makes it Super Blue doesn't agree with the hydraulic seal in the clutch cylinder. That's what I've read.

It had been groaning and squeaking with a sticky throw, but literally as soon as I turned the car on with the new brake fluid the clutch was back to normal. Really weird.

$teady$upreme
12-04-2005, 03:55 AM
But my instructor taught me the method turbojunkie just mentioned~


Originally posted by Mawhitey
Not to scare you, but this method can cause the Master Cylinder to fail, pushing the piston past it's normal travel and allowing the seals to catch on the rougher, unused part of the master cylinder walls.
This makes the seals flip, and therefore fail to pressureize. I am sorry to scaremonger, but this i have had this a few times in the past, hence i only use an air pressurized bleeder now