Cycle ABS to get air out

[3500GMC]

Any cheats? TEC2 would be nice yeah.

2000 Buick Century 3.1. Had to do both rear brake lines from ABS unit to hoses. Used a mighty vac with canister. Haven't done the pump and bleed yet.

 

[ak diesel driver]

none other than the obvious slide the tires on snow,grass,gravel etc

 

[btfarm]

none other than the obvious slide the tires on snow,grass,gravel etc

Agreed. I usually take a spin out in the pasture if there's no snow. Do about four attempts at lockup to full stop.

Sent from my SCH-I535

 

[Will L.]

No, really officer! I was just trying to reset the antilock brakes...just ignore all the tire marks!

 

[Ed HD]

I agree. Find a gravel road, pasture, etc and cycle the ABS a few times. Thing is, you gotta bleed the calipers out, then do that, then bleed, then do it one more time, to make sure all the air's gone...

 

[3500GMC]

Forgot to check back, yes all is well and the Boooickk is healed. Took it for the ride of it's life down back behind the house, lol. Had grass aflyin' :hihi:

 

[schiker]

I just replaced my hydro boost, master cylinder, and flushed the brake lines. I used a Motive Power Bleeder.

I bench bled the MC and installed it with fluid. I connected the brake lines and left them just barely snug at first. I attached the motive bleeder and pumped it up slightly and cracked the lines right at the MC and let a little fluid out of each line and tightened them. Then I started at farthest wheel (back passenger side) and started flushing the lines. I opened the bleeder and let ~ 2 cups of fluid flush out it started to look much cleaner so I went to drivers side back tire repeat after a cup the fluid looked really clear so I let a little more out of passenger side then drivers side again. Next did front passenger side first and then drivers.

I attached a clear hose to the front and saw at least one air bubble come out but it wasn't much.

I DID NOT cycle the antilock brakes to try and bleed further but the pedal feels more firm than before. However, my anti-lock brakes don't seem to work anymore anyway and my anti lock light is on. I have done a few hard stops back to back and it stops fine no excessive fade etc. I am thinking the motive power bleeder does a good job of flushing out the system and makes it a one person job.

What if anything do I need to do to bleed the antilock system further???

Did you feel a spongy pedal or what before skidding around the back yard???.

 

[3500GMC]

Yeah the pedal was low and not quite as firm. It will take a few tries. In general when the system is opened even with new fluid there are tiny bubbles that get sent throughout so until they become one bubble, it's very hard to get ALL the air out in one shot. This has been my findings anyway..

 

[schiker]

I have only done a handful of bleeding jobs the worse being the hydraulic clutch. I like the Motive Power Bleeder at least for bigger brake jobs. I was a little surprised how long it took to bench bleed the master cylinder but I wasn't shocked because the hole to get fluid into the piston is small. Same with the clutch they are real small holes and just doing the manual style pumping, hold, and bleed method doesn't discourage making bubbles or collect them together very well. If you have a lot of air it seems to froth the fluid at the master cylinders trying to pull fluid into the piston area from the reservoir.

To me the way the motive power bleeder just puts a small psi on the system pushes the fluid out with laminar flow. It keep the fluid calm ( no air bubbles or major turbulence) and pushes the fluid out like a plug. It is like a faster gravity bleed that can push bubbles out easily. To me this is key as vacuum style bleeder have to pull through that little hole at the bottom of the reservoir and pulling a vacuum isn't exactly the same thing as the air bubbles might separate or act differently with the small hole restriction behind them. Better than nothing but not as good as pushing them out.

I recommend it for bleeding systems and will try and adapt the method to other bleeding operation when I can.

 

[3500GMC]

Sounds like a worthy tool (motive) as it is an 'encouraged' gravity of sorts. The problem with a mighty vac is your always picking up bubbles from the threads on the bleeder. Makes it uncertain if the air is really OUT. All kinds of nooks and crannies in a hydraulic brake system.