Most people will bleed the brakes by pushing the pedal to the floor, this is what destroys the original old Master Cylinder.
During the Master Cylinders life it only travels in a small path and eventually wears a little metal away and creates a small ridge or lip at the end of the travel. Now when you bleed the brakes you push the internals of the Master Cylinder past their normal wear area and cut or damage the o-ring and cause a small leak that will get bigger.
I always place a block of wood under the brake pedal to only allow it to be bleed under normal or less brake travel, I havent replaced 1 Master Cylinder yet since I have started to do this.
Last brake job I bought a vacuum pump and now I can bleed all the brakes by my self!
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Mark V
Look for me on the PS3 network, I am usually playing Uncharted 2 demo right now. My PS3 name is delorean6683 "New" Rock Auto Forum Discount
They say if you play a Microsoft CD backwards you hear satanic messages. Thats nothing cause if you play it forwards it installs Windows....
1998 Windstar GL 3.8L
1998 Explorer XLT 4.0L SOHC
2001 Corvette 6 speed 5.7L
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