rebuilt calipers now pedal is soft after bleeding

**Konakid** · 01-07-2009, 03:19 PM

I have replaced everything in the corona's brake system bar the metal lines, booster and front rubber lines.

Have bled it and the pedal goes straight to the floor still, has absolutely nothing.

When i got the car 3 months ago it was fine, brakes worked but since it wasnt really in a drivable state i took it to the shops only twice. Then i swapped to RA60 calipers, rebuilt them, new rotors, pads, new rear wheel cylinders, machined drums, new drum shoes, then i bled them and they were barely working.

I get the car home, bleed them properly (starting with the furthest away wheel from the brake master) pedal has pretty much nothing again, pop the bonnet and there is brake fluid pissing out between the master and booster. Completely rebuild the master, new stainless steel piston as the old one was pitted, new gasket, $260 bucks later, bolt it up, new fluid, bleed, absolutely nothing again.

I can pump the pedal up and it gets harder, i can visually see the master sucking in fluid as the pedal is depressed but then when released it forces the fluid back up the reservoir and bubbles like there is a clot in the lines and there is a lot of pressure behind it.

All vac lines are still connected to the booster and it seems to be working perfectly.

Calipers have the bleed screws pointing up

Master has not been bench bled

Fluid comes out of all four pistons in a steady stream.

Pedal is completely soft, will go to the the floor on first push but can be pumped up.

Anyone got any ideas?
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**RA35GT** · 01-07-2009, 03:21 PM

Did you bleed the master on the car?

**WDE_BDY** · 01-07-2009, 03:30 PM

How big are the RA60 calipers compared to the originals? Master may just be the wrong size for the calipers and therefore not able to push enough fluid.

Callum

**parrot** · 01-07-2009, 03:56 PM

Bench bleed your master cylinder, after making sure the front piston is located correctly within the cylinder, and the piston stop screw is located correctly once the piston is in front of it.

It has to be a master cylinder thing.

If you are bench bleeding anyway, I would dismantle and check you have assembled correctly.

**Konakid** · 01-07-2009, 04:55 PM

Thanks for the replies!

I had the master rebuilt for me and when i got it back, it had blue fluid coming from both front and rear ports so im guessing it had already been bled?

The RA60 calipers are the same size as the originals but they allow for a vented rotor.

Maybe i have rebuilt the calipers incorrectly?

**RA35GT** · 01-07-2009, 05:33 PM

It wouldnt hurt to bleed the master cylinder on the car as well. As you never know what happened to the master cylinder after they bled and tested the master cylinder.
http://www.cygnusx1.net/Supra/Librar....aspx?S=BR&P=7

Its pretty hard to rebuild the calipers incorrectly dood and if you did you would of seen leaks by now.

if after bleeding the master and calipers again the pedal is still soft.

Get four hose clamps and clamp all the brake lines. Then test the pedal. If it comes good then you have a caliper issue. Remove one clamp at a time to isolate the faulty caliper.

If the pedal is still soft you either still have air in the lines or the master is no good.

**frostyadonis** · 01-07-2009, 06:46 PM

did you adjust the rear brake shoes?
cos if you didn't the wheel cylinders will have excessive travel in the piston area
and i take it you fitted ventilated disc rotors with the ra60 calipers

**parrot** · 01-07-2009, 07:18 PM

A trap I have seen is people thinking they can bleed the master on the car by releasing the piston stopper bolt on the side of the master cylinder. The pistons then move back and you are screwed.

**wa5** · 01-07-2009, 09:04 PM

Konakid wrote..... Calipers have the bleed screws pointing up END

Are the bleed screws right at the top IE could any air be getting stuck in the calipers?
is it possible that you have reversed the calipers... IE left on RHS and vice versa?

**Konakid** · 01-07-2009, 10:47 PM

Thanks all, will bench bleed the master tomorrow and see how i go.

**CrUZida** · 02-07-2009, 12:31 PM

Originally Posted by 7M-GTE MX73

It wouldnt hurt to bleed the master cylinder on the car as well. As you never know what happened to the master cylinder after they bled and tested the master cylinder.
http://www.cygnusx1.net/Supra/Librar....aspx?S=BR&P=7

Its pretty hard to rebuild the calipers incorrectly dood and if you did you would of seen leaks by now.

if after bleeding the master and calipers again the pedal is still soft.

Get four hose clamps and clamp all the brake lines. Then test the pedal. If it comes good then you have a caliper issue. Remove one clamp at a time to isolate the faulty caliper.

If the pedal is still soft you either still have air in the lines or the master is no good.

^^ Do what this says ^^

Don't bother bench bleeding the master, just do it on the car (with care, and a big rag).
So much easier to do it on the car.