Brake bleeding - need sanity check

[FasterBass]

Hey all,

Need your sage advice.

09 Yukon SLT 4wd. Yesterday I noticed drivers front caliper was stuck and rotor was HOT. Ok, no problem. $100 and new caliper later I figured I'd be fine.

Swapped the new caliper in, used a pressure bleeder, no brakes. Hmm. I remember when doing the brakes the first time I just did pads and rotors that I could not unstick one of the rear bleeders. Seems like I'll have to do a full bleed, so went and replaced the rear caliper too.

Status: two new drivers side calipers.

Go to bleed and went through 3 bottles of fluid just trying to get the driver's rear brake to stop producing bubbles. It is at this point I figure I need to do an abs bleed. Worth noting that I also tried to drive it and try to activate abs. Pedal was horrible but would stop with some pumping.

Now here is where I think I messed up. Followed instructions on my Innova 5610, which said to start at drivers front caliper. Bled that one, moved to pass front. DID NOT REFILL Reservoir. I didn't have a sense of how quickly the abs bleed depleted the reservoir and I think I ran the mc dry. When I checked the bottle on pass front it was a frothy mess. Drivers front was not bubbly.

I then proceeded to try to bleed my way out of this mess to no avail. I probably pressure bled and abs bled the truck another 3 or 4 times respectively and kept getting frothyness from the abs bleed on the front circuit.

So here's where I am. After screaming a few hundred f bombs and sleeping, I think I must have hurt the original 140k master cylinder. It's either that or the abs pump is fried, but since the truck was braking fine earlier today I don't think that's it. Can anyone with more experience lend their 2 cents here before I light this truck on fire (or have it towed to a shop)? Thanks all.

 

[FasterBass]

Hey all,

Need your sage advice.

09 Yukon SLT 4wd. Yesterday I noticed drivers front caliper was stuck and rotor was HOT. Ok, no problem. $100 and new caliper later I figured I'd be fine.

Swapped the new caliper in, used a pressure bleeder, no brakes. Hmm. I remember when doing the brakes the first time I just did pads and rotors that I could not unstick one of the rear bleeders. Seems like I'll have to do a full bleed, so went and replaced the rear caliper too.

Status: two new drivers side calipers.

Go to bleed and went through 3 bottles of fluid just trying to get the driver's rear brake to stop producing bubbles. It is at this point I figure I need to do an abs bleed. Worth noting that I also tried to drive it and try to activate abs. Pedal was horrible but would stop with some pumping.

Now here is where I think I messed up. Followed instructions on my Innova 5610, which said to start at drivers front caliper. Bled that one, moved to pass front. DID NOT REFILL Reservoir. I didn't have a sense of how quickly the abs bleed depleted the reservoir and I think I ran the mc dry. When I checked the bottle on pass front it was a frothy mess. Drivers front was not bubbly.

I then proceeded to try to bleed my way out of this mess to no avail. I probably pressure bled and abs bled the truck another 3 or 4 times respectively and kept getting frothyness from the abs bleed on the front circuit.

So here's where I am. After screaming a few hundred f bombs and sleeping, I think I must have hurt the original 140k master cylinder. It's either that or the abs pump is fried, but since the truck was braking fine earlier today I don't think that's it. Can anyone with more experience lend their 2 cents here before I light this truck on fire (or have it towed to a shop)? Thanks all.

Also worth noting that after all that bleeding I have 0 pedal. Like, I had to use the parking brake to keep from hitting the back of my garage when parking it. It's worse now than when i had just replaced the calipers.

 

[wjburken]

Sorry to hear that you’re having issues.

When bleeding brakes, you did commit one cardinal rule which is letting the MC run dry.

The other thing I see is start in the caliper furthest away from the MC and work your way closer. Right Rear, Left Rear, Right Front, Left Front. I personally have had good luck with a vacuum bleeder. The one I have I bought from Harbor Freight for approx $100. It comes with a large reservoir that mounts to the MC to help keep it from running dry.

If it was me, I’d bleed your Master Cylinder then bleed your 4 calipers then do the ABS bleed and then bleed your 4 calipers again to get any residual air out.

Make sure to keep an eye on the MC level.

Others may have different suggestions.

 

[FasterBass]

Sorry to hear that you’re having issues.

When bleeding brakes, you did commit one cardinal rule which is letting the MC run dry.

The other thing I see is start in the caliper furthest away from the MC and work your way closer. Right Rear, Left Rear, Right Front, Left Front. I personally have had good luck with a vacuum bleeder. The one I have I bought from Harbor Freight for approx $100. It comes with a large reservoir that mounts to the MC to help keep it from running dry.

If it was me, I’d bleed your Master Cylinder then bleed your 4 calipers then do the ABS bleed and then bleed your 4 calipers again to get any residual air out.

Make sure to keep an eye on the MC level.

Others may have different suggestions.

Thanks for the help! Yeah, normally I would always do farthest from MC to closest but was following the instructions on the Innova 5610. Whenever I do the pressure bleed I always start from farthest away.

Ok, so MC first. Total PITA but what the hell. I'll try anything at this point.

 

[solli5pack]

When I did my Yukon with the Tech 2 it had me follow the same procedure. D/S then P/S front then P/S D/S rear. It is a real pita. You almost need 3 people, one in the truck, someone on the calipers and another keeping the reservoir full. Also big help to have all 4 wheels off. I would say you have some air trapped in your system. Go grab a gallon of brake fluid and flush it good!

 

[RichardCranium]

Sorry to hear that you’re having issues.

When bleeding brakes, you did commit one cardinal rule which is letting the MC run dry.

The other thing I see is start in the caliper furthest away from the MC and work your way closer. Right Rear, Left Rear, Right Front, Left Front. I personally have had good luck with a vacuum bleeder. The one I have I bought from Harbor Freight for approx $100. It comes with a large reservoir that mounts to the MC to help keep it from running dry.

If it was me, I’d bleed your Master Cylinder then bleed your 4 calipers then do the ABS bleed and then bleed your 4 calipers again to get any residual air out.

Make sure to keep an eye on the MC level.

Others may have different suggestions.

Solid procedure here.

And don't fret, you'll get it back. It's just going to take some time and repeating the procedure over a few times. I can also tell you, as a former BMW Master Tech, getting air into the ABS system can be a pain. Even with proper tools to help you electronically bleed the ABS system. What we always did, once we had enough brake pedal to feel safe enough to drive, is take the vehicle out and stomp/hold the brake pedal a few times. Get it into ABS mode, force the pump to push that air out. If you don't have what you need to properly bleed the ABS system itself, this will be another useful procedure to proper bleed that system.

(don't bring your beer with you on that drive to activate ABS, you'll have a waste and a mess)

 

[wjburken]

Solid procedure here.

And don't fret, you'll get it back. It's just going to take some time and repeating the procedure over a few times. I can also tell you, as a former BMW Master Tech, getting air into the ABS system can be a pain. Even with proper tools to help you electronically bleed the ABS system. What we always did, once we had enough brake pedal to feel safe enough to drive, is take the vehicle out and stomp/hold the brake pedal a few times. Get it into ABS mode, force the pump to push that air out. If you don't have what you need to properly bleed the ABS system itself, this will be another useful procedure to proper bleed that system.

(don't bring your beer with you on that drive to activate ABS, you'll have a waste and a mess)

Used an open patch of grass or a gravel road to bleed the ABS module many times.

 

[j91z28d1]

something sounds off to me.. why was the caliper locked up? you said it wasn't stuck?


if above advice doesn't work, try this.. at this point I'd throw a new master on it. bench bleed that.. once installed do a slow manual bleed, if it will gravity bleed some, let it do that. (I haven't had good luck with vac bleeder and power bleeders. they just make a mess and waste fluid for me.) if it won't, have someone push the pedal down and hold with the bleeder open. close before lifting, till you get fresh clean fluid at all four corners. then run your abs bleed, but I found what worked for me is to not follow the manual, just run thru the program, do what it asks of the pedal, but don't worry about opening the bleeders, then see what you have for pedal and go from there. if it's decent do the pump hold bleed thing. if it still goes to the floor at that point, you're byond my knowledge haha.

the auto bleed really needs that pressurized filling system it call for to work correctly. I've never had any luck with it. but I run thru the program to active the pump and stuff, seems to work.

 

[mattbta]

MC seal(s) could be shot if the pedal went all the way to the floor during manual bleeds. Want to keep a 2x4 under to prevent from overextending and thus blowing out the seal(s).

 

[FasterBass]

something sounds off to me.. why was the caliper locked up? you said it wasn't stuck?


if above advice doesn't work, try this.. at this point I'd throw a new master on it. bench bleed that.. once installed do a slow manual bleed, if it will gravity bleed some, let it do that. (I haven't had good luck with vac bleeder and power bleeders. they just make a mess and waste fluid for me.) if it won't, have someone push the pedal down and hold with the bleeder open. close before lifting, till you get fresh clean fluid at all four corners. then run your abs bleed, but I found what worked for me is to not follow the manual, just run thru the program, do what it asks of the pedal, but don't worry about opening the bleeders, then see what you have for pedal and go from there. if it's decent do the pump hold bleed thing. if it still goes to the floor at that point, you're byond my knowledge haha.

the auto bleed really needs that pressurized filling system it call for to work correctly. I've never had any luck with it. but I run thru the program to active the pump and stuff, seems to work.

I bought a new mc under the assumption that, after 140k let's take an old part out of the equation. I'll bench bleed, install and update. Probs sunday

 

[Just Fishing]

I have had good luck using a suction bleeder for issues like this.
Put it on the bleed nipples and let it chooch while pumping the brakes.

The one I have uses compressed air to create the suction, super cheap on amazon.

https://www.amazon.com/gp/product/B013WKCKW0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

You will need to do all 4 in order, and you might need to do it twice + the ABS if the pedal is still spongy afterwards.

 

[iamdub]

I bought a new mc under the assumption that, after 140k let's take an old part out of the equation. I'll bench bleed, install and update. Probs sunday

Are you pushing the pedal to the floor? If so, you may have damaged the seal(s) in the MC.

My experience: '08 Tahoe, ~150K miles. Bleeding brakes just as I've done countless times on many vehicles. RR, LR, RF and when bleeding the final corner, the LF, the pedal went soft and would not firm up. Nothing but bubbles in the hose. I know I didn't let the MC go dry. After starting all over again with a soft pedal no mater what, I got a new MC. Bench bled it, installed it and bled the system all over again. Been great ever since.

Turns out, the bore of the MC wears where the piston is routinely cycled through the miles and miles of normal driving. This leaves the far end of the bore, where the piston never goes, unworn and slightly tighter. When you floor the pedal during bleeding, you're repeatedly jamming the piston, with its aged and weakened seals, into a tighter bore. I'm sure it's more common for a failure to not happen from this, but there are instances. So, yeah, drop a brick or 2x4 or something to block full pedal travel.

Also, I've never stopped during a brake job, put the wheels on, drove to a grassy field or gravel pit to cycle the ABS, drove home, got back under the car then bled the [now hot] brakes again. When you turn the key on and all the cluster lights come on for the self-checks, the ABS solenoids are also cycled. I hang the hose and bottle on the corner I'm bleeding, crack the bleeder and test the pedal. It just needs to "leak down" under firm foot pressure and not be a totally loose pedal. You want it to take about three seconds to make a full stroke. If you still have to really press on it, the bleeder is too tight. Give it an ~1/16 turn or so and test the pedal again. To bleed, slowly but steadily push the pedal a few times to your pedal block. Then, just as you're beginning another stroke, turn the key to on (not start) while maintaining your slow stroke. Give it a stroke or two, turn the key off, a few more strokes, key on, few strokes, etc. Check the hose for bubbles and top off the MC reservoir. I suggest you borrow a friend to watch the hose or even just use their phone if they're unavailable to hang out. Set the phone up to watch the hose and Facetime/video chat it while you watch it with your phone from the driver seat. When you see a few strokes cycles with no bubbles, go close the bleeder screw, set up and repeat at the next corner.

If you have a power bleeder, use it as normal (but keep an eye on that MC reservoir!) but have someone cycle the key a few times while you're operating the bleeder at each corner.

 

[Hrocks]

I have had good luck using a suction bleeder for issues like this.
Put it on the bleed nipples and let it chooch while pumping the brakes.

The one I have uses compressed air to create the suction, super cheap on amazon.

https://www.amazon.com/gp/product/B013WKCKW0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

You will need to do all 4 in order, and you might need to do it twice + the ABS if the pedal is still spongy afterwards.

I'm all in with Just Fishing...I used to do amateur road racing and bled the brakes (by myself) on my Corvette every week that I was going to be at the track. (brake fluid is hyGROscopic: it attracts moisture and is deadly on the track. People say that they "boiled" their brake fluid...what they really did is boil the couple of percent of water in their braking system. Your pedal goes to the floor. Not something you want to have happen to you when you're going foot on the floor "till you see God" then brake.) In any event, the gizmo that JF references above is good, however the one that's right next to it is even better. (and foolproof) https://www.amazon.com/dp/B09PYBGVSQ/ref=syn_sd_onsite_desktop_0?ie=UTF8&psc=1&pd_rd_plhdr=t

I have a Snap On bleeder that's almost exactly like the BILITOOLS unit above. The accessory refilling unit really makes it idiotproof. I often used ATE brake fluid because it came in two different colors so that you could clearly see when you had expunged ALL of the old brake fluid. That way I didn't need anyone to pump the brakes or constantly guestimate when I had cleared the system of the old fluid. I would buy that kit and you can use it not only for bleeding the brakes, as you can extract almost any liquid. e.g. --if you have a lawn mower, tractor, etc.etc. you can suck the oil out of it without having to turn the thing upside down. In any case, spending the $65 for the combo above will save you from going to a shop and getting ripped off having them bleed the system for you, AND you will know that there's NO air in you system.

 

[FasterBass]

Tuesday night update. Bench bled the new mc (poorly, I might do it again with an actual bleed kit) installed. Pressure bled first, then abs utilizing the closed bleeder method first. Then pressure bled again. No pedal. Tried the open bleeder abs bleed method, then pressure bled again. Now I have no pedal but if I pump it up I have a solid pedal. Ran out of time and fluid to do any more.

Def think the MC was on the way out or the culprit. With the pedal pumped up it seems the brakes a much more responsive to pressure.

Based on @Hrocks suggestion I just purchased a vacuum kit as a last ditch attempt. Also got a MC bleed kit and will try that one more time once it comes in.

Based on the above symptoms ( has a decent pedal once pumped up) do you all think I just need to keep going here, or is there something else I am missing?

 

[j91z28d1]

man what a hard bleed. I've not dealt with anything this bad.

i do think it pumping up to something is atleast a sign you have something but a lot of air somewhere. hope the vacuum bleeder to works.

if all else fails I've used this way before..

Brake Bleeding Bottle

Brake Bleeding Bottle: Recently I had the pleasure of replacing the hydraulic clutch slave cylinder on my wife's Mini Cooper, which is worthy of an I'ble in itself (check back later...). Once the new one was installed, it has to have the air bled from the line exactly as …

www.instructables.com

Get a small Gatorade bottle, clean it and dry it well, some clear hose the inside the size of the bleeder nipple, drill a hole in the cap, stick the hose to the bottom, fill about have way with fluid. open the bleeder, put the hose on it and just pump the pedal. the air will come out in the down stroke, on the up it will suck the fluid from the bottle back in instead of air. I have a homemade one hanging on my tool box at work, I use it sometimes when I don't have a 2nd person handy. you're so deep in this, I can't say I know why it's fighting you so badly. just throwing out things that have worked for me before.

 

[Dustin Jackson]

@FasterBass If it makes you feel better man I'm also having trouble bleeding my brakes, I am going to try a hand vacuum bleeder unit also and see if that helps

 

[wjburken]

I have had good luck with this vacuum bleeder from Harbor Freight. Bought when I had a tough time bleeding a friends brakes for them.
HOLT INDUSTRIES Pneumatic Air Operated Brake Bleeder with Auto-Refill Kit - Item 57057 https://hftools.com/app57057

 

[Hrocks]

I have had good luck with this vacuum bleeder from Harbor Freight. Bought when I had a tough time bleeding a friends brakes for them.
HOLT INDUSTRIES Pneumatic Air Operated Brake Bleeder with Auto-Refill Kit - Item 57057 https://hftools.com/app57057

Should work fine. Same principle.

 

[FasterBass]

Thanks for the support y'all. I've been working on cars for more than 20 years and I can honestly say this is the toughest non-fabrication problem I've had on a vehicle. This is for sure the most modern vehicle I've worked on, and my lack of experience with abs systems and OBD2 shows.

Two things that are keeping me going:

1. If I pump up the brakes there doesn't seem to be any fluid leaking from lines. The garage was dry after letting it sit a few days.

2. I'm fixing this thing out of pure spite for being such a pain in the ass.

 

[FasterBass]

@Hrocks I got the one you suggested. Be here Thursday.