jlwdvm

Switching over to the Brembo BBK for my 2011 GT while I also do suspension up grades. I took the calipers off the front when I started the project (10 days ago) and capped the hard lines. I think as the car has sat, most of the brake fluid has leaked out (master cylinder looks almost empty). I will be changing the rear pads too, as well as upgrading to Motul brake fluid. I haven't touched the brake pedal since I started. Do I need to bleed the master cylinder? How?

JAJ

Before you touch anything, top up the master cylinder. Then hook everything up and bleed the wheel cylinders. If there's any possibility that the ABS pump hasn't lost its prime, this will do it. If you can't get a firm pedal after that, then a trip to a dealer or a shop with the right tools is in your future.

Next time you undo the brake lines, push the brake pedal about half way down and block it there. That blocks off the master cylinder reservoir and prevents the fluid from draining out.

jlwdvm

I started bleeding the brakes last night...finally!. Bleeding according to the instructions in the shop manual with a vacuum pump that can maintain 25"Hg (I'm using an electric medical vacuum used for surgery). I sucked out about 175ml from the right rear, 125 from the left rear, and about 75 from each front Brembo. I've opened up my second bottle of Motul (I'm flushing the whole system). The vacuum tube never filled completely with fluid, I couldn't tell if I was sucking air into the tube from where it slipped over the bleeder screw. The tube seemed very snug. Anyway, I turned the car on and the brake peddle went to the floor initially, but I was able to get it firm by pumping several times (I just wanted to see how it felt). I'll have to get some help and bleed the conventional way to see what kind of peddle feel I can get. Hope I don"t have to have it towed to a brake shop! Any thoughts?

jlwdvm

Vacuum bleeder

ShaneM

motive speed bleeder, about $65 makes the job a snap.

rebus

I used the motive bleeder to flush the system and it works fine. There is a lot to be said for manual bleeding, you can get a lot more applied pressure with the pedal, and if done properly can't be beat. I gravity bled mine followed by manual bleeding. Remember to start at the farthest wheel working towards the closest and never let the master cylinder run dry. If air gets trapped in the ABS distribution block it can get tricky getting it out.

jlwdvm

When I removed the front breaks, most of the fluid dripped out of the system over several days while I got the front sway bar on, springs and struts installed, etc. There was a little fluid left in the master cylinder once I notices what was happening (very little). If air gets into the master cylinder will it come out when the brakes are vacuum or manual bled? If air got into the ABS is there any other way to get it out besides having it hooked up to a scanner at a brake shop? I never touched the brake pedal while the lines were open until I got to the rears. Depressed it half way and blocked it to keep them from draining.

ummduh

well if the master went dry you're going to need to bench bleed it to get the air out. it is usually nearly impossible to get that air out without bench bleeding. then you'll have to rebleed the entire system again.

never let the master go dry.