Coroner81
Newbie
With the ports blocked, and the truck off, the pedal is rock hard, and doesn't budge. No fade, no movement.With the MC ports plugged, did the pedal eventually start to sink or was it firm for a good while?
Assuming it held the entire time, I’d use some hose clamp pliers to pinch both rear hoses and see if it firms up. Could be a hose expanding or maybe a cylinder extending too far?
This is a long shot, but may be worth looking at this video. Somewhere in the back of my mind I remember someone having a soft pedal that was remedied this way.
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There's only one rear hose on my truck, it's 1 year old, and I'm replacing it tomorrow for poops and giggles just to eliminate something else. There's definitely an air issue, and not just a soft pedal. I keep getting streams of bubbles while bleeding, and the pedal will not pump up and build pressure at all. I'll check out the video in a few when my better half is done watching her stuff on TV. Thank you
Not trying to be a dick, but, my brakes work and yours don't. I'd try gravity bleeding it, especially since you said that you have removed the abs...
It is a very simple system once the abs is removed. Either you aren't good at bleeding brakes, or you have another bad master cylinder. Gravity bleeding will at least eliminate option 1.
If there are no leaks and no abs - The master is the only place that can allow air to enter.
I'm glad your brakes work. Gravity bleeding won't find where air is getting in. I have no problems bleeding brakes. It's not rocket surgery. The MC is working fine. Plugging the ports results in a rock hard pedal.
I'm going with option 3. Air is getting in the lines. Somewhere.
Air can enter anywhere there's a fitting. Not just at the MC. And yes, it was bench bled until piston travel didn't exceed 1/8".
2 pf my bleeder screws were corroded, and didn't seal completely when tightening. Didn't notice that right away because everything was wet from bleeding. That could possibly allow air back in while bleeding.
Wheel cylinders are brand new, and have new bleeder in them. I have used teflon on the bleeder, and still get the same issue. This isn't a trickle of small bubbles. This is a long stream of huge bubbles.