Brake bleeding

apsmith49921 · Feb 19, 2023

So I put new stainless lines and ats brembos on the car. I cannot get the pedal to feel correct. I have bled all the calipers and go no bubbles but the pedal is still total garbage.

One thing to note. When I changed the front brakes I let the reservoir run dry on accident so the front lines emptied completely

ttocs · Feb 19, 2023

get a power bleeder from harbor freight

cobrajeff96 · Feb 19, 2023

You need to make sure that the calipers are fully bled, and by that I mean both bleeder screws on each caliper. You now have two per side. And so the correct bleeding sequence will be:

Passenger rear
Driver rear
Passenger front (inside / outside / inside)
Driver front (inside / outside / inside)

You will go through a bit more fluid now because of the extra bleed steps and the overall larger volume of the front calipers. Do it the old fashioned way, the two-person method. It's tried and true and will never fail as long as the master cylinder has fluid above its drain and you don't accidentally release the brake pedal with a bleeder screw still open. Don't use old fluid, even if it's the newish fluid that you just ran through the system. Needs to be brand new from unopened bottles.

ttocs · Feb 20, 2023

if you got air into the lines before the abs pump, the pump needs to be cycled to get the air through it and bleed it. There are computers that can do it for you or when I put my baers on I didn't have the computer so I found a dirty parking lot and got it up to speed, then jumped as hard as I could on the brakes to get the abs pump to cycle and work the air through it. After that I was able to use the power bleeder to get the rest out.

cobrajeff96 · Feb 20, 2023

I've never had that issue, myself. When key is off, ABS module should be wide open. I wouldn't think you'd need to cycle it, should just bleed without any special considerations. The later models S197+ I've heard are different and usually require the external computer.

On the subject, you may need to bleed the master cylinder if air was allowed to get below the fluid reservoir, it should have bleeder screws on the side of it. OEM m/c that is.

apsmith49921 · Feb 20, 2023

I tried bleeding the master. I didn't get much air out of it. Bleed both screws on it as well

ttocs · Feb 20, 2023

cobrajeff96 said:
I've never had that issue, myself. When key is off, ABS module should be wide open. I wouldn't think you'd need to cycle it, should just bleed without any special considerations. The later models S197+ I've heard are different and usually require the external computer.

On the subject, you may need to bleed the master cylinder if air was allowed to get below the fluid reservoir, it should have bleeder screws on the side of it. OEM m/c that is.

yes if you get air into the abs pump it takes a little bit of work to get it out. I had the same problem when I did my swap and changed the MC.

J_lope82 · Feb 20, 2023

I just bled mine yesterday because I replaced the hydroboost. I did it the old school way with two people. You said you ran the master cylinder dry. Don’t let it run dry or you will need to start all over. Check it after you bleed each caliper to make sure it’s not dry.

ttocs · Feb 20, 2023

this is a great way to help

lwarrior1016 · Feb 20, 2023

The guys at wilwood told me, the easiest way is to have 3 people. Take the lid off the master, crack a front and rear bleeder, then have a 3rd person push the pedal all the way down nice and slow. That will move the most fluid. Then tighten the bleeders, release the pedal, and do it again. Make sure the master stays full.

apsmith49921 · Feb 20, 2023

I should have clarified I ran the master dry when I installed the new lines not last night when attempting to bleed them

oz95gt · Feb 20, 2023

If you're car is a GT you might need a Cobra master cylinder to account for the extra pistons , remember reading years ago about GT to Cobra rotor and caliper swap you would have a soft/doughy pedal with the GT master cylinder

lwarrior1016 · Feb 20, 2023

gt master cylinder works just fine with cobra brakes. The Ats brakes may require a different master for optimal pedal feel, but shouldn’t be a problem for bleeding.

96blak54 · Feb 20, 2023

The guys at wilwood told me, the easiest way is to have 3 people. Take the lid off the master, crack a front and rear bleeder, then have a 3rd person push the pedal all the way down nice and slow. That will move the most fluid. Then tighten the bleeders, release the pedal, and do it again. Make sure the master stays full.

100 % make sure the reservoir stays full! I found myself making circles to all 4 corners bleeding each brake once and move to the next brake untill no air in the lines. This took awhile.

cobrajeff96 · Feb 21, 2023

I was gonna say having two bleeders open might drain that m/c quicker than you can check it.

apsmith49921 · Feb 21, 2023

It's a cobra so master shouldn't be an issue. Would it be helpful to have a real vacuum bleeder? The big one from like HF or something

96blak54 · Feb 21, 2023

apsmith49921 · Feb 21, 2023

Ok the air one is on sale for 25 bucks

ttocs · Feb 21, 2023

that is the one I used. You will still probably need to cycle the abs pump after you bleed them, and then bleed them again after it is cycled. Like I said I just found a dirty parking lot and you just have to get the abs to kick in and it will work the air out into the lines where you can then bleed it.