Still air in brakes after bleeding for a week

[JoeMakesUVOs]

LOL, yeah on the adjuster assembly not being a part of the brake hardware kit, the parts gods have deemed it to be a different part of the brake assembly on the majority of drum brakes out there, because it technically isn't involved with holding the brake shoes to the backing plate. Glad to hear that you decided to put new shoes on as well, and although by what I saw in your pics, the shoes appeared to be OK and could possibly been fine for reuse. But since you spied cracking, and you also have/had wheel cylinder/brake shoe adjuster issues along with the wheel cylinder rebop, a definite wise choice to go ahead and replace the shoes as well. Hopefully you took each brake apart (separately!) and did some cleaning to the brake baking plate to get rid of brake dust, brake fluid, and oily contaminants as well. I also use this opportunity to clean the back of the axle flange & axle seal to make sure nobody is leaking as ANY fluid contamination (Brake fluid or gear oil out of the diff) getting on the shoes will adversely affect the brakes, and you get to get right back into the drums to fix it...
And, back on the adjuster subject - The part you have circled is the slip washer that fits on the cad plated, (lowest part in the adjuster part picture, in a "goldish" color) adjuster fork, (note the notch in the part) and its job is to give the adjuster wheel (the "star" looking notched & threaded wheel) the ability to spin on the other, threaded adjuster (zinc plated) without binding against the unthreaded adjuster fork, and allow the two forks to spread the brake shoes out as needed to keep the adjustment correct to the drum. The tang/notch of the two pieces is so the slip washer doesn't spin around, but I think it'll be OK if it does, because if it does spin, it'll eventually find a place to bind itself at, probably on the brake shoe. I definitely recommend a little bit of lube on it (I usually use some anti-sieze compound, but DO NOT let that stuff get all over the place, which it can certainly do if you get it on your hands, fingers, or shop rags...) And lastly, don't forget going forward (provided the brakes bleed out correctly, and I'm sure they will this time) to occasionally USE THE EMERGENCY BRAKE (just "once in awhile" is fine) if you have an automatic transmission equipped truck, since the adjusters do their adjusting via E-brake application, but no worries about it if your truck has a manual trans (and be sure the E-brake DEFINITELY WORKS then, at all times!) and hopefully this round of repair gets you stopping right.

 

[Scooterwrench]

First thing take the master off and bench bleed it,that will take the air out of that part of the system.
Second,stop pumping the brake pedal! All you're doing is foaming the air in the lines and pulling the air back into the master. Have your helper mash the brake pedal down then you open the bleeder screw for about three seconds and close the bleeder then tell your helper to take his foot off the pedal and repeat until no more air spits out of the bleeder. Check the fluid in the reservoir after no more than three bleeds.
Don't worry about that stupid brake warning light. Once you get pressure on both sides of the system that differential switch will reset and the light will go out. That light was the lamest device ever put on brake systems. It only comes on after there is a failure,by then you know you've got no brakes.

 

[Caman96]

EXACTLY what I commented on, exactly illustrated with what I see.

See post #13

 

[HawkDsl]

Tip for BRAKE LIGHT on OBDI trucks... after you sort out the fix on your brakes, disconnect the battery for at least 30 seconds, and it will reset the brake light.

 

[Schurkey]

I definitely recommend a little bit of lube on it (I usually use some anti-sieze compound

Anti-seize is a THREAD lubricant, with the understanding that threaded fasteners are moved into position (torqued) and then they don't move again until it's time to disassemble them. Might be decades of NON-relative movement.

Anti-seize is powdered metal in a grease-like carrier fluid. Usually powdered aluminum, sometimes powdered copper, rarely powdered nickel. The grease carrier may burn away on high-heat applications. Any way you look at it, anti-seize is an ABRASIVE when used on parts that have relative movement. It's only a lubricant when the powdered metal acts as microscopic "ball bearings" between threads that haven't had relative movement and would have rusted together since they were torqued into place.

There are many quality lubricants specially-made for brakes. Anti-seize is not among them.

Don't worry about that stupid brake warning light. Once you get pressure on both sides of the system that differential switch will reset and the light will go out. That light was the lamest device ever put on brake systems. It only comes on after there is a failure,by then you know you've got no brakes.

Of course not. It also comes on when the park brake is depressed. And having the light come on does not mean you have "no" brakes, as you may still have perfectly-functional front (but not rear) or rear (but not front) brakes.

It may come on when the ABS is unhappy, but then it does represent some sort of failure, just not the failure you're describing--where one part of the hydraulic system has unequal pressure compared to the other part.

 

[Scooterwrench]

Anti-seize is a THREAD lubricant, with the understanding that threaded fasteners are moved into position (torqued) and then they don't move again until it's time to disassemble them. Might be decades of NON-relative movement.

Anti-seize is powdered metal in a grease-like carrier fluid. Usually powdered aluminum, sometimes powdered copper, rarely powdered nickel. The grease carrier may burn away on high-heat applications. Any way you look at it, anti-seize is an ABRASIVE when used on parts that have relative movement. It's only a lubricant when the powdered metal acts as microscopic "ball bearings" between threads that haven't had relative movement and would have rusted together since they were torqued into place.

There are many quality lubricants specially-made for brakes. Anti-seize is not among them.

Been doing it for years,has never failed me. I re-wet it with non-detergent 30w when servicing later. As you know I'm running anti-seize in my crankcase and it's been in there for just under 4000 miles now. If anti-seize were so abrasive that motor would be ground down into powder by now. It's probably the reason I haven't had to get out and kick rods out of the road.
It's basically powdered bearing material,aluminum,bronze and graphite. Anybody running up there in the rust belt should be smearing a little anti-seize on their brake adjuster screws.

Of course not. It also comes on when the park brake is depressed. And having the light come on does not mean you have "no" brakes, as you may still have perfectly-functional front (but not rear) or rear (but not front) brakes.

It may come on when the ABS is unhappy, but then it does represent some sort of failure, just not the failure you're describing--where one part of the hydraulic system has unequal pressure compared to the other part.

My ABS took a $hit and the light was one but the brakes still worked fine and if you lose pressure in one half of the system you're gonna know it before the stupid thing lights up.

 

[MountainDont]

No anti-seize on my threaded adjuster! It only gets brake lube grease, as per the Chilton manual. CRC or Permatex. I have some of each. I'm sure Ford and Chevy make good stuff, too. I used the Permatex, not anti-seize. If you want to see anti-seize in my photos, look at the axle hub.(*)

Here is the photo of the adjuster spring which I hate! The Chilton manual said to put it on last, but since it goes on the back, it's a royal pain to snap on. Driver side shown.

As for resetting the Brake Warning Light, here is the procedure:
1. Shut the bleeder.
2. Start the engine.
3. Begin slowly pressing the brake pedal. The light will eventually go out, possibly after several cycles of the pedal.
4. Turn the engine off.
5. Key in run. Observe Red light off.
6. IF you bleed with the Key On, Engine Off, and you have daytime running lamps, you will need to use a battery charger to keep from killing it.
7. Pedal person must remember to be careful with the speed he presses brake, especially after the engine has been on and the vacuum assist is still strong and the pedal is still soft. You can set the light very easily when bleeding the rear.

(*)Note: the Chilton manual said to put anti-seize on the backing plate where the shoes rub, but of course that is not visible in this picture. New cylinder shown.

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[MountainDont]

Success!

After a prolonged amount of bleeding, pitfalls, and bunny trails, I have finally fixed the brakes. I am, however, a bit disgruntled that they seem a bit softer than I want them. At least there is no air anymore.

It turns out that the rear wheel cylinder(s) was definitely the culprit of the air. After the new cylinders were put in, I noticed that we had drained out the fluid in the tank. My educated helper is of the opinion that I should have done a bench bleed. I don't have a kit to do that, not to mention that this would surely put air in the system by removing the master cylinder. In any case, we did all four wheels, the rears more than once, then ran the ABS bleed* twice. We then bled all four wheels again, ran another ABS bleed, and then one final time. The last 20 or so bleed attempts, we found no air. (Before changing the slave cylinders, we got air all the time.)

Test drive was a success. Forward and reverse tried out and felt good. I forgot to pull the E-brake yet. I'll try that and see. I thought they adjusted in reverse.

* Oh, and we tried a bit of a new thing. Remember me discussing about the "button" on the ABS module, that's normally covered with a little dust cap? And that I've read that you need a special tool to press it? Well, I had my edu-ma-cated helper take a screwdriver and mash that thing during the ABS automated bleed. He said that air came out!

We switched positions, but he is more prone to setting the red brake light because he presses the brake pedal too hard during the rear bleed. Anyway, we ran another ABS bleed with me at the "button" on the Kelsey-Hayes. It was all I could do to hold it, and I wasn't ready. The second time with me on the button, it felt like I had 80 pounds of pressure on that thing and it was barely enough, and then it squirted a little brake fluid!

I think that was important, but how much, I don't know. I had tried bleeding that button countless times before, and never had seen a drop of fluid until then.

 

[Schurkey]

Success!

Excellent.

I am, however, a bit disgruntled that they seem a bit softer than I want them. At least there is no air anymore.

Bleed the master cylinder as described below.

It turns out that the rear wheel cylinder(s) was definitely the culprit of the air.

Kinda expected.

I noticed that we had drained out the fluid in the tank. My educated helper is of the opinion that I should have done a bench bleed.

DO NOT remove the tubes from the master cylinder. Unbolt the master from the booster. Tip the front of the master cylinder "down". Tickle the primary piston, you may see air bubble into the reservoir from both the primary side, and the secondary side.

I thought they adjusted in reverse.

Duo-Servo generally do. Leading/trailing, no.

Remember me discussing about the "button" on the ABS module, that's normally covered with a little dust cap?

That dust cap and "button" is NOT on the ABS module. It's on the combination valve, which is bolted to the ABS module.

What you're seeing is the stem of the metering/holdoff valve, which affects the front brakes.

I've read that you need a special tool to press it?

Generally when bleeding with a pressure bleeder.

Well, I had my edu-ma-cated helper take a screwdriver and mash that thing during the ABS automated bleed. He said that air came out!

I've seen the Youtube videos where that happens.

Didn't work for me. I got nothing.

 

[MountainDont]

Bleed the master cylinder as described below.

DO NOT remove the tubes from the master cylinder. Unbolt the master from the booster. Tip the front of the master cylinder "down". Tickle the primary piston, you may see air bubble into the reservoir from both the primary side, and the secondary side.

Do I leave the cap on the reservoir while doing this? I'm kind of wondering how far it will tilt down with the 3 lines still attached. Like 20 degrees or less?

I've seen the Youtube videos where that happens.

Didn't work for me. I got nothing.

As for the button pressing, I think my helper just put his full weight onto the brake during the ABS bleed. I mean, that button was stronger than my leverage with a screwdriver could muster. When I was doing the ABS bleed, I had just used casual pressure on the pedal. I've seen a bunch of YouTube videos about the button. Air and fluid escaping. But I hadn't seen anyone do it during the ABS bleed.