June 13, 20169 yr My 2002 OBW daily driver: The rear caliper banjo bolt was loose and leaked much of the fluid in the system. I've pumped the pedal at least 50 times at each caliper and pedal still goes to the floor. Is there tons of air from going empty or the MC was compromised from going dry?
June 13, 20169 yr Author I tried the ABS cycling and it wouldn't work by grounding the appropriate pins, the ABS never cycled. But I've bled ABS cars before without doing the ABS sequence thing.
June 14, 20169 yr maybe I'm confused - if you assure there's fluid in the reservoir and bleed one corner at a time - do you ever get rid of all air observed at each corner? Are you saying you do, and the pedal still goes to the floor? or, can you never get the air out at even one corner? there are people that claim, on older cars, using full travel of the pedal to bleed can compromise the MC seals (from corrosion or pitting???) wonder if a gravity bleed or one of those power-pump (w'ever, can't remember right now) might work?
June 14, 20169 yr Couple of weeks ago I gravity bled my brakes and my pedal is firm again. Try it. Good luck, Sam
June 14, 20169 yr maybe I'm confused - if you assure there's fluid in the reservoir and bleed one corner at a time - do you ever get rid of all air observed at each corner? Are you saying you do, and the pedal still goes to the floor? or, can you never get the air out at even one corner? there are people that claim, on older cars, using full travel of the pedal to bleed can compromise the MC seals (from corrosion or pitting???) wonder if a gravity bleed or one of those power-pump (w'ever, can't remember right now) might work? That was my first thought as I've seen it happen. Age is far less relevant than care. 5 years old in a humid climate with no fluid changes can be a problem where frequent fluid changes and a dry climate can have little issue after decades. Next question: exactly what procedure are you using to pump the pedal? The proper way is to pump the pedal, hold it down, then open the bleeder for just a moment (to keep from bottoming the MC), close it, repeat.
June 14, 20169 yr Author I got it working now. while bleeding (two methods - pedal and one man pressurized tank on MC tool) there was no end to the air bubbles, pedal had zero resistance. Probably pushed the pedal 50-100 times at each wheel. Also used a one man pressurized tool to push fluid through. It wasn't the method. I shortened my pedal travel (not pushing to floor) and bled for the 4th time and it worked. Probably coincidence, maybe not? I think it had so much air in the system from driving with leaking fluid/empty MC, it just took forever to get all the air out. And because of all the air not much fluid was moving in the beginning either. Id pump the pedal 20 or 30 times and the reservoir level would barely drop. Today it dropped much faster once I got close to the end. Every Subaru I've bled was easy. But with a caliper or MC repair you just get localized air bubbles, I've replaced calipers and just bled that one line lots of times even though it's said you "can't do that". Easy peasy. I think this time the air was wide spread and far more of it.
June 14, 20169 yr Yea, if you get air in the master cylinder, it really needs to be removed and bench-bled to get all the air. The bottleneck from the master bore down into the lines is so extreme that you'll almost never push all the air through it. It's possible you've pushed enough through now to get it...
June 14, 20169 yr I had the problem with a Ford Transit a couple of weeks ago that I destroyed the master cylinder seals by pushing the pedal all the way down. Result was pumping air in each time I push the pedal... Was also such a never ending story. After changing the master cylinder, everything was fine instantly.
June 15, 20169 yr Like chux said, once you get air in the MC it's almost impossible to get it all out without bench bleeding. At times I've had to resort to unbolting the MC from the booster and pulling it forward and pushing the front of the MC down so any air in the bore can get up through the vent port and back into the reservoir.
June 15, 20169 yr Author Ahhhhhh okay. You guys have had a hard time bleeding MCs before? I wonder how many MCs are deemed failed because they just need bled? Think that happens?
June 15, 20169 yr Getting the ABS to cycle is tricky, I did it once on my '00obw. It took a few tries to get it to do it. It was something with grounding those pins then the ignition had to go on, then the pedal had to get pressed within so many seconds and held or something. Hi grossgary, sent you a pm but I don't think the forum notifies for pm's anymore.
June 15, 20169 yr Ahhhhhh okay. You guys have had a hard time bleeding MCs before? I wonder how many MCs are deemed failed because they just need bled? Think that happens? It definitely does
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