smoove2022

Hey I was bleeding my front brakes yesterday for about 2 hours... This was just after I intalled the earls braided lines. I accidentally let the fluid in the master cylinder resevoir empty completely (for the front brakes). Should it have taken that long to bleed them? After 2 hours and 2 bottles of brake fluid I was still getting air bubbles comming out at the calipers. Do I have air in the master cylinder? Can I bleed the master cylinder while it's still on the car? When I was bleeding it (2 person method) we noticed that the brake fluid in the resevoir was spurting up, is this right? Funny thing is, even with the air that is still in brake lines my cars stops ALOT better with the earls lines...

Petes 84Z28

Yes.

Only if you can raise the rear of the car high enough so that the MC sits level; otherwise, you need to remove it and clamp it in a vice. Don't spill brake fluid on your paint - keep a bucket of water or a hose handy to wash off any spilled fluid immediately.

Completely normal.

Don't 'pump up' the brakes to build pressure when bleeding the MC; you'll just aerate the fluid and make it more difficult to bleed. Use slow, steady strokes.

smoove2022

So assuming I can raise the back of the car so the MS is level and bleed it while it's on the car, will I need to bleed the lines again at the calipers? Are there plugs available at autostores for bench bleeding the MS otherwise?

studdmstr

More than likely the air bubbles that you are seeing are coming from around the threads of the bleeder screw. After 2 hrs of bleeding I'm pretty sure that you have all the air out of the master cylinder. If your pedal feels firm and not spongy, then more than likely you have all the air out.

smoove2022

Still feels a bit spongy

studdmstr

Then yep you probably still have air. Back to bleeding you go!

Chickenman35

You have air in the MC. It has to be " Bench bled" ( Procedure is called " Bench bleeding" but can be done on the bench or in the car ) You can bleed it on the car but it's a PITA and will take two people.

Go to your local Parts supplier. Ask for a bench bleeding kit. Comes with every new M\Cyl. Should cost about $2.50

Note that with some kits the little tapered fittings that go into the M\C ports are not long enough. If that is the case remove the front and rear lines from the prop valve and install them on the M\C that you're trying to bench bleed. Stuff the tapered adpater in the ends of the tubes.

You

ronterry

You can try taking her for a good criuse, and then rebleed the system. Don't forget to take a rubber malet to the calipers while bleeding the system. This will losen up air bubbles that like to stick inside the calipers.
Worked for me, had the same problem.
I have ABS on my Vette, so I would also kick in the ABS on a dirt road several time.

Ron

smoove2022

Hey thanks guys! Do I need to bleed at the prop valve too?

SweetS10v8

your getting lots of good info, but I hope its not an internal leak past your piston cup seals in the master cylinder.

Just after reading how much you have bled and it still is spongy makes me wonder if the the cup seals are allowing fluid to pass over the them from the high side to the low pressure side of the piston. Making them spongy....

If nothing else works, you might look there.