Bleeding Brakes

[Rocket Man]

I used to pressure bleed back when master cylinders were iron. Made a cap with an air fitting on it. For sure the best and easiest way but with today's plastic reservoirs it doesn't seem like a good idea. Old vacuum pump and a Mason jar with a couple tubes soldered in. (pretty much as shown above). The old brake pedal deal never did work for me. Sometimes just leave the bleeder open and let gravity do it would work, usually not. Used to really hate any brake work that opened the system.

Now I hate antifreeze, seems like there is always a seep somewhere undetectable.

Why do you feel pressure bleeding is not a good idea with plastic reservoirs? The bleeder I’ve been using has a pressure gauge on it and it pumps up like a garden sprayer. Just pump it up to 15 lbs and it’s not going to hurt anything, that’s nothing in terms of pressure. It does say to not exceed 20 lbs but at 15 I only had to pump it up once and then add a couple pumps to bleed all 4 brakes and run 4 pints through it.

 

[Larryjb]

If 15 or 20 psi were to crack or damage the plastic reservoir, that it would have been ready to blow apart anyway, probably when you'd need it most.

 

[dnt1010]

2009 Tahoe with Active Barke system GM Code J92 I will be replacing ABS assembly unit (Module/Modulator valve/ABS pump/Accumulator) so the entire system will be opened up and full of air. Can a brake bleed be done using the Motive pressure bleeder without using a scan tool to activate the brake bleed program? From what i am seeing around the internet the Active brake systems are very finicky and must be done right or it will have problems.

 

[Rocket Man]

I’m not sure as I’ve never tried that but I would think if you’re replacing the abs assembly you’ll need to use a scan tool. You should be able to bleed the regular system so the brakes work good and then drive it to a shop to bleed the ABS.