Bleeding Brakes with ABS

[8thTon]

OK, I've never bled brakes on any vehicle with ABS. I tried searching with little useful results - can someone fill me in on what is required on the Ranger?

 

[91stranger]

Really? Start from the passenger rear and work you way closer and closer to the master cylinder. What's the back story? i.e. Why are you needing to bleed brakes?

 

[8thTon]

I know how to bleed brakes in general and have done it many times. My understanding was that the ABS valve blocked the lines and had to be told to open first.

The fluid is dark and I may have a minor brake drag caused by air - it needs to be bled and probably never has been.

 

[91stranger]

There's some video's on youtube for this specific issue. Something about the R-ABS valve. Nothing I've ever dealt with.

 

[adsm08]

If you have not opened the system above the ABS unit then you don't need to do anything special. The ABS bleed procedure is only needed if air has been introduced into the unit. The valves do not block the lines between the master cylinder and the wheel ever. One of the safety requirements for building an ABS system is that the failure of said system cannot impact the function of the braking system as a whole.

The valves you are thinking of are between the ABS fluid pump and the wheels, and are what allow for the unit to selectively and rapidly apply the brakes without you pumping the pedal. They just shut off the pump from the rest of the system. You need to do the ABS bleed when air gets into the ABS unit because it can dump air into an otherwise bled system during an ABS event.

The poor man's version is to bleed the brakes, go out and lock the wheels up a few times, and then bleed again.

 

[pjtoledo]

If you have not opened the system above the ABS unit then you don't need to do anything special. The ABS bleed procedure is only needed if air has been introduced into the unit. The valves do not block the lines between the master cylinder and the wheel ever. One of the safety requirements for building an ABS system is that the failure of said system cannot impact the function of the braking system as a whole.

The valves you are thinking of are between the ABS fluid pump and the wheels, and are what allow for the unit to selectively and rapidly apply the brakes without you pumping the pedal. They just shut off the pump from the rest of the system. You need to do the ABS bleed when air gets into the ABS unit because it can dump air into an otherwise bled system during an ABS event.

The poor man's version is to bleed the brakes, go out and lock the wheels up a few times, and then bleed again.

agreed, but it's less dramatic if done on a slippery surface. wet pavement, grass, gravel, dirt etc. due to a longer stop it gives the ABS more time to cycle and purge.

 

[adsm08]

agreed, but it's less dramatic if done on a slippery surface. wet pavement, grass, gravel, dirt etc. due to a longer stop it gives the ABS more time to cycle and purge.

Well, yes. Its best done down hill in the snow, but that's not always an option.

I usually try to do it several times on a dry road, if I can't trigger an ABS service bleed with a scanner. My Solus does most US and Asian vehicles through 2012, but 10 and 11 were roll over years for a lot of makers, so I can get it to talk to a lot of cars through 2015 because the software didn't change. I don't get a lot of work on stuff newer than that.

 

[8thTon]

If you have not opened the system above the ABS unit then you don't need to do anything special. The ABS bleed procedure is only needed if air has been introduced into the unit. The valves do not block the lines between the master cylinder and the wheel ever. One of the safety requirements for building an ABS system is that the failure of said system cannot impact the function of the braking system as a whole.

The valves you are thinking of are between the ABS fluid pump and the wheels, and are what allow for the unit to selectively and rapidly apply the brakes without you pumping the pedal. They just shut off the pump from the rest of the system. You need to do the ABS bleed when air gets into the ABS unit because it can dump air into an otherwise bled system during an ABS event.

The poor man's version is to bleed the brakes, go out and lock the wheels up a few times, and then bleed again.

Thank you, that's what I was looking for!

I don't believe it was ever opened up, the fluid looks old. I should be able to do a normal bleed, making sure the reservoir stays full.

 

[adsm08]

Thank you, that's what I was looking for!

I don't believe it was ever opened up, the fluid looks old. I should be able to do a normal bleed, making sure the reservoir stays full.

Yes.

 

[Dirtman]

A scanner with ABS bleed feature only sets you back about 300 bucks these days. But yea obviously if you haven't replaced the abs pump and just want to do a flush there's nothing fancy needed. Just pay closer attention to the master cylinder reservoir than normal. Worst case on a non-abs truck if the master cylinder runs dry is you start all over lol. An ABS truck is gonna bite you in the ass a bit more if you do that...

 

[adsm08]

A scanner with ABS bleed feature only sets you back about 300 bucks these days. But yea obviously if you haven't replaced the abs pump and just want to do a flush there's nothing fancy needed. Just pay closer attention to the master cylinder reservoir than normal. Worst case on a non-abs truck if the master cylinder runs dry is you start all over lol. An ABS truck is gonna bite you in the ass a bit more if you do that...

I'd get a pressure bleeder bottle. I'm working on making one, I'm just not working very hard.

Basically the bottle is full of brake fluid, the bottle is pressurized (mine will run off a tire) and it pushes old fluid out and new in at the same time.

The only car I have found so far that kind of setup didn't work on because of the ABS was a Chevy Malibu Maxx. That we did need the Solus for, but can say from first hand experience no non-hybrid Ford will give you that kind of trouble.

 

[8thTon]

I usually use the vacuum bleeder kit from my MtyVac - it's not the best because it can pull air in around the bleeder screw treads and then you can't tell if the bubbles you see are from that or the system. Still, it's bled a lot of brakes and worked well enough.

 

[adsm08]

I usually use the vacuum bleeder kit from my MtyVac - it's not the best because it can pull air in around the bleeder screw treads and then you can't tell if the bubbles you see are from that or the system. Still, it's bled a lot of brakes and worked well enough.

Yeah, I don't like the vac pump for exactly that reason. I have a pry bar that I can stick in between my seat and brake pedal and it will hold the pedal down while I got work the bleeder, if I need to do them myself.

 

[fastpakr]

On smaller systems I'll sometimes flush enough fluid through to get fresh fluid at the bleeder, then run a long hose from the bleeder back into the reservoir and leave the valve open while I cycle fluid through. Works especially well on motorcycles.

 

[8thTon]

Yeah, I don't like the vac pump for exactly that reason. I have a pry bar that I can stick in between my seat and brake pedal and it will hold the pedal down while I got work the bleeder, if I need to do them myself.

It helps if I only crack the bleeder very slightly.