Reason fro replacing Brake Master Cylinder
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Reason fro replacing Brake Master Cylinder
Did you need to replace your Brake Master Cylinder?
I think mine is needs to be replaced.
Replaced brake pads then proceeded to bleed brakes, 3 times using these methods. (NOTE: after installing the rear pads when I stepped on the brake pedal to let the pistons come out, I heard like a spring give. Now I do not know if that thing I heard is a seal that failed or a return spring / pin that gave.)
Also when bleeding the brakes, as soon as I open the nipple right before the pedal reached the floor, there is a noise emitted from the master cylinder like a groan.
1) Using Motive brake bleeder Right Rear / Left Front / Left Rear / Right Front
Got all bubbles out. Pedal travel was deep, slightly past throttle pedal.
2) Manually bled brakes In same order, 2 man method. I never let the fluid go
past 3/4 full on the resevoir. Still same result.
3) Manually Bled it doing the furthest from the master cylinder first. Same result
made sure that ABS was actuated to let any bubble escape.
Thanks
I think mine is needs to be replaced.
Replaced brake pads then proceeded to bleed brakes, 3 times using these methods. (NOTE: after installing the rear pads when I stepped on the brake pedal to let the pistons come out, I heard like a spring give. Now I do not know if that thing I heard is a seal that failed or a return spring / pin that gave.)
Also when bleeding the brakes, as soon as I open the nipple right before the pedal reached the floor, there is a noise emitted from the master cylinder like a groan.
1) Using Motive brake bleeder Right Rear / Left Front / Left Rear / Right Front
Got all bubbles out. Pedal travel was deep, slightly past throttle pedal.
2) Manually bled brakes In same order, 2 man method. I never let the fluid go
past 3/4 full on the resevoir. Still same result.
3) Manually Bled it doing the furthest from the master cylinder first. Same result
made sure that ABS was actuated to let any bubble escape.
Thanks
Last edited by Drift4; Apr 8, 2007 at 04:06 PM.
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Check your pedal assembly under the dash, there are springs and bearings down there maybe something has gone afoul. Generally master cylinders are pretty robust and just to blow apart all at once.
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Thanks Sponge Bob, but yeah I checked it already, there is no spring in the pedal cluster for the brake pedal......I don't know what you are talking about bearings?...there are no bearings on the pedal cluster.
I am wondering if someone has an exploded picture of the master cylinder?
Last edited by Drift4; Apr 8, 2007 at 04:08 PM.
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This is a dumb question but it has to be asked. There are 2 nipples to bleed the brakes on each caliper -- the inside and the outside. You got both, correct?
Last edited by JTB; Mar 31, 2007 at 05:24 PM.
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Once you button everything up and drive the car what symptoms are you experiencing? Does the car brake normally; I assume not as you keep trying to bleed them.
So has this popping/groaning sound continued since bleeding or are you still trying to bleed the brakes? Sorry if I’m asking simple suggestions bit I don’t know here you are at in the process.
So has this popping/groaning sound continued since bleeding or are you still trying to bleed the brakes? Sorry if I’m asking simple suggestions bit I don’t know here you are at in the process.
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Does the car brake normally; I assume not as you keep trying to bleed them.
So has this popping/groaning sound continued since bleeding or are you still trying to bleed the brakes? Sorry if I’m asking simple suggestions bit I don’t know here you are at in the process.
So has this popping/groaning sound continued since bleeding or are you still trying to bleed the brakes? Sorry if I’m asking simple suggestions bit I don’t know here you are at in the process.
the pop sounded only once, the groaning is everytime you open the bleeder valve/nipple and when the pedal is just about to reach the floor is when you hear it.
Last edited by Drift4; Apr 1, 2007 at 06:26 PM.
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Did you let the fluid level get low? Sometimes air can get into the master cylinder side and you have to take it off and bench bleed it. I think this may have happened to me because I'm having the same exact issues you are after my brake job.
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2) Manually bled brakes In same order, 2 man method. I never let the fluid go
past 3/4 full on the resevoir. Still same result.
Can you please elaborate in this technique? So your saying air can get trapped in the master and not be able to be bled?...isn't that like installing a new one and bleediing it? I don't know where it would trap air while bleeding the entire brake system?
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Sure I read it, but the symptoms sound like air trapped in the master cylinder. Scroll down a bit on this page or search for "master cylinder bench bleeding"
http://www.babcox.com/editorial/tr/tr502b.htm
http://www.babcox.com/editorial/tr/tr502b.htm
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Sure I read it, but the symptoms sound like air trapped in the master cylinder. Scroll down a bit on this page or search for "master cylinder bench bleeding"
http://www.babcox.com/editorial/tr/tr502b.htm
http://www.babcox.com/editorial/tr/tr502b.htm
"When replacing a master cylinder, be sure to bench bleed it before installing it in the vehicle"
I have not replaced my master cylinder yet...I have a brand spanking new one ready to go in. But thanks for the suggestion.
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Sigh... I know what it is and when it's recommended. I also was trying to get a point across that air might have gotten in there and gotten trapped (which is why you bench bleed a new one in the first place). Just trying to give you a possible avenue for repair without replacing something that might not need it... no need to bold and underline things.
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Sigh... I know what it is and when it's recommended. I also was trying to get a point across that air might have gotten in there and gotten trapped (which is why you bench bleed a new one in the first place). Just trying to give you a possible avenue for repair without replacing something that might not need it... no need to bold and underline things.
but I will let you guys know what the outcome is, i will be replacing the master tomorrow, and i will definetly run fluid throught it....and do a complete re-flush along with the clutch.
Last edited by Drift4; Apr 8, 2007 at 04:13 PM.