Weird brake bleeding problem

[JoeMadoo]

Hey there, I have a strange issue with my brakes. Basically every round of bleeding I do, the pedal gets worse and worse feeling. After 4 rounds, the pedal goes straight to the floor. Now I wouldn't consider myself stupid, I've done this many times before. Just putting that out there. I also have the ABS deleted and new lines ran.

A few weeks ago, I bought some ss lines and installed all 6 of them. Did 1 or 2 rounds of bleeding using the friend method. The pedal had some sponginess, but stopped the car just fine, so I ran with that for about a week. Decided to finish bleeding them today so I bought a quart of fluid and made my rounds to every caliper, adding fluid to the reservoir when necessary. Again using the friend technique. The fluid is clear and bubble free coming out of every caliper with good flow. Yet the brake pedal drops to the floor with only the pressure of the push rod going in to the master cylinder, pretty much whether the bleeder valves are open or closed.

There are no visible leaks from any of the lines, calipers, or the master cylinder. I used brand new Dot 3 fluid.

Thinking it could be something internal in the master cylinder? I can see it shooting fluid up into the reservoir when the brake pedal is pressed to the floor.

[jlevie]

The pedal going to floor with no bleeders open and no visible leaks would mean that the master cylinder has failed. There's a good chance that a failed master cylinder will leak into the brake booster, but not always. Once the master cylinder has been removed, use a bit of rag tied to a wire to probe the bottom of the master cylinder. If there is brake fluid there the booster will have to be replaced as brake fluid will kill a booster pretty quickly.

[JoeMadoo]

Thanks I will look into it.

[jalopi]

Just throwing this out there - not to insult someone I don't know - but does your friend know what he's doing? I know pumping a pedal is simple... but there are some people who just can't figure it out...

Try gravity bleeding your brakes, see if that works. (crack the bleeders open and wait until they start dripping. Let them all drip for 10 minutes or so while watching the master res. level. Then close the bleeders up)

Hope that works for you