Brake bleeding problem

So i went to my good trusted filipino mechanic friend, (hes an actual mechanic with his shop) and I was told it was the master cylinder that was mad, so i will be replacing that and get back to you guys when I do

you got fluid coming out of the other 3 wheels, right? I hesitate to attempt to fake any level of brakes knowledge knowing Blaine is in this thread, but the m/c only has 2 ports so if you're only not getting fluid out of one wheel I would doubt that the m/c is the issue. I believe the front brakes each have their own port on the combo block, so it could be that the issue is there if not in the line or at the caliper itself. But I would seriously doubt the m/c is the issue here.

If you feel like spilling a bunch of brake fluid you could disconnect the line to the front right on the combo block and hit the brakes. If you get fluid out, your problem is further downstream. I guess I might then disconnect the line at the caliper to see if if its the line or the caliper. And as a last resort I'd completely remove the bleeder screw to see if you get fluid out of the caliper. Although I might actually try that last step first now that I think about it.
 
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you got fluid coming out of the other 3 wheels, right? I hesitate to attempt to fake any level of brakes knowledge knowing Blaine is in this thread, but the m/c only has 2 ports so if you're only not getting fluid out of one wheel I would doubt that the m/c is the issue. I believe the front brakes each have their own port on the combo block, so it could be that the issue is there if not in the line or at the caliper itself. But I would seriously doubt the m/c is the issue here.

If you feel like spilling a bunch of brake fluid you could disconnect the line to the front right on the combo block and hit the brakes. If you get fluid out, your problem is further downstream. I guess I might then disconnect the line at the caliper to see if if it’s the line or the caliper. And as a last resort I'd completely remove the bleeder screw to see if you get fluid out of the caliper. Although I might actually try that last step first now that I think about it.
well the m/c has always had a tiny leak, so i’ll still change that, i’m not sure if it was just the front right because the front left was good but i also think the rear left was a bit funky? or nearly all of them were weird, i’ll change the m/c if that doesn’t work, i will change all the calipers. I inspected the lines and they’re all good as far as i can see + was told
 
Fwiw, I've been using Motive products Power Bleeder for almost 30 years in all my cars, including the tj with great results. It makes bleeding foolproof, IMHO, and a one person job. They make different size adapters for all brake fluid reservoirs. Of course, this is only to help you with bleeding not other problems you may be having.
 
Fwiw, I've been using Motive products Power Bleeder for almost 30 years in all my cars, including the tj with great results. It makes bleeding foolproof, IMHO, and a one person job. They make different size adapters for all brake fluid reservoirs. Of course, this is only to help you with bleeding not other problems you may be having.

thank you this actually could help
 
thank you this actually could help

Another nice thing about the Motive Products Power Bleeder is that you don't have to keep filling the brake fluid reservoir as you bleed the calipers. You fill the container once and then do all your bleeding.
 
From my experience when bleeding if you pump the pedal you WILL introduce air to the system. Also pads, rotors, shoes and drums does not add up to a complete overhaul. That would require calipers and wheel cylinders to also be replaced. But I’m not the brake guy. Get in touch with Blaine he solves brake issues and instructs how to bleed properly.

B
 
you got fluid coming out of the other 3 wheels, right? I hesitate to attempt to fake any level of brakes knowledge knowing Blaine is in this thread, but the m/c only has 2 ports so if you're only not getting fluid out of one wheel I would doubt that the m/c is the issue. I believe the front brakes each have their own port on the combo block, so it could be that the issue is there if not in the line or at the caliper itself. But I would seriously doubt the m/c is the issue here.
Depends on the system. ABS has 2 ports at the combo block. Non ABS has 3. The front brake hard lines plug into 2 ports which are common to each other inside the block or a Tee. If you are not getting fluid out of one side in the front, it isn't the master. There is only one line to the rear axle which then Tees off to both sides. If you aren't getting fluid out of one side properly, again, it isn't the master.
If you feel like spilling a bunch of brake fluid you could disconnect the line to the front right on the combo block and hit the brakes. If you get fluid out, your problem is further downstream. I guess I might then disconnect the line at the caliper to see if if its the line or the caliper. And as a last resort I'd completely remove the bleeder screw to see if you get fluid out of the caliper. Although I might actually try that last step first now that I think about it.
Good.
 
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From my experience when bleeding if you pump the pedal you WILL introduce air to the system. Also pads, rotors, shoes and drums does not add up to a complete overhaul. That would require calipers and wheel cylinders to also be replaced. But I’m not the brake guy. Get in touch with Blaine he solves brake issues and instructs how to bleed properly.

B

Well not too long ago i did install some new RC lines that have been working well, i already changed the drums before, i just re did the parking brake cable, and replace all the internals for the rear drums, only thing i haven’t touched is actually the calipers
 
Well not too long ago i did install some new RC lines that have been working well, i already changed the drums before, i just re did the parking brake cable, and replace all the internals for the rear drums, only thing i haven’t touched is actually the calipers

How about the soft lines up front?
When I was in your situation an email then phone call to @mrblaine solved all my issues.


B
 
Blaine's probably tired of repeating the best way to bleed brakes.
@AndyG thread about his brakes was the last time I saw it, but can't find it now.
 
Blaine's probably tired of repeating the best way to bleed brakes.
@AndyG thread about his brakes was the last time I saw it, but can't find it now.

Best I remember:

Crack the valve

One pedal stroke

Close the valve

Not pump and hold.


Next day - one small burp at each bleeder to catch entrained air.

If you get on the phone with Blaine, he knows so much and he is so specific you need to have something to write on, and be ready for school.
 
Best I remember:

Crack the valve

One pedal stroke

Close the valve

Not pump and hold.


Next day - one small burp at each bleeder to catch entrained air.

If you get on the phone with Blaine, he knows so much and he is so specific you need to have something to write on, and be ready for school.

I still have my notes from a few conversations. 😉
 
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Best I remember:

Crack the valve

One pedal stroke

Close the valve

Not pump and hold.


Next day - one small burp at each bleeder to catch entrained air.

If you get on the phone with Blaine, he knows so much and he is so specific you need to have something to write on, and be ready for school.

This is the only way to bleed em that has worked for me. 🤷🏼‍♂️
 
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Yeah, he's definitely spoken out against the pump it up and hold, then break the bleeder free while under pressure pedal falls to floor then retighten bleeder strategy. I have a buddy who wants to do it that way. I just shake my head and do what he says.

I don't recall pumping up to build pressure being part of his recommended approach, which I've seen touted here & elsewhere. The only thing I'll add to what AndyG said above is to leave the pedal pushed to the floor while the screw is being tightened (which was implied, but not explicitly stated). Once the system is closed you can release the brake pedal. Then repeat.
 
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Yeah, he's definitely spoken out against the pump it up and hold, then break the bleeder free while under pressure pedal falls to floor then retighten bleeder strategy. I have a buddy who wants to do it that way. I just shake my head and do what he says.

I don't recall pumping up to build pressure being part of his recommended approach, which I've seen touted here & elsewhere. The only thing I'll add to what AndyG said above is to leave the pedal pushed to the floor while the screw is being tightened (which was implied, but not explicitly stated). Once the system is closed you can release the brake pedal. Then repeat.
For the TL,DR crowd, our method is below in bold if you want to skip the rest of the drivel.

Pumping the pedal on modern masters aerates the fluid. The more you pump, the more tiny bubbles you get in the fluid. That is bad and good. Bad because fluid shouldn't have tiny air bubbles in it, good because you can use that to tell when you have fluid from the master at each corner when you do a flush. When you see the tiny bubbles in the clear hose. Go to the next corner.
My method that we use is what works for us, every single time. Others do it lots of different ways, I've tried most of them and I'm not able to make them work as well as a good 2 person manual bleed. They doesn't mean they don't work or aren't successful for others, I just can't make any of them work every time.

The problem with vacuum bleeders is sealing the straight threads of the bleeder screw at each wheel cylinder.
The problem with speed bleeders is you can't tell if you have a problem because you aren't able to see the flow and rate at each corner.
The problem with pressure bleeders is you can't always get enough pressure to induce the turbulence needed to get the crap out of the piston bores.
The problem with reverse pressure bleeding is you can push the crap that is in the piston bores up into the combo valve and master bore.

Here is ours again-

Cap off of the master and I flip it upside down and lay it back over the opening to slow down a splash that can happen. If the cap isn't off or loosened, a fast drop in reservoir level can produce a vacuum which makes the bleeding process harder. While the cap is vented, it is a very small vent designed to allow the pressure in the reservoir to equalize to atmospheric without leaking fluid. In case you ever wondered why some of the caps look the way they do.

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Fluid level full in the master reservoir.

Engine off, key on to power up the dash, parking brake off. You need to know if the brake light is tripping which indicates a shifted shuttle valve.

The valve moves when the pressure is too high on one side. The low pressure side is being closed off or mostly closed off to prevent loss of fluid in the event of a leak. Good safety feature, terrible for brake bleeding. While we do use a lock out tool that replaces the switch in the combo valve to stop the shuttle from moving, we bled 100's of rigs before that and always managed to get it done easily. In fact, I kinda like not using one because that tells me the system is functioning, the valve will move when needed, and the circuit is good so it will work when it should. Roughly around 03-04, they changed something about the switch. Before then, we never had a single instance of the valve shifting during bleeding. After that, we get some rigs that had to have the dash light reset at every pedal push.

What put us onto looking for a better way or to bleed with the key on was I could hear the valve in the combo block clicking as it shifted.

I use a bottle to collect the fluid and a clear hose on the bleed screw. The hose end in the bottle does not have to be under fluid. That is an old wive's tale. If you want to verify why, simply open a bleeder and watch what happens. Fluid will run out which means air is not going in and again, we still have the issue of not being able to seal straight threads at the bleed screw so even if the requirement was to have the hose in fluid to stop air from going into the caliper, it would still get in around the threads, it doesn't. Even if it did, the bleeder is the high point, fluid would push the air up to the bleeder inside the caliper and it would leave at the next bleed cycle exactly as designed.

If you are not having the helper push the pedal down enthusiastically enough that you have to hold the hose on the bleed screw, then they need to do so with some more enthusiasm. A pedal push down should squirt fluid out of the bleeder and across the floor 3-5 feet if you didn't have the hose in place.

1- you open bleed screw with as wide a swing as possible
2- helper pushes pedal to the floor and holds it at the bottom
3- close bleed screw and tell the helper to let the pedal up.

Repeat 5-7 times per corner.


I start with a gravity bleed. (remember the hose in fluid silliness?) When I have fluid dripping out of the bleeder at each corner, I know I can start the manual bleed. You can also use the gravity bleed to diagnose. If you open the bleeder on a full system and fluid doesn't come out after enough time that it should have, there is a problem.

The tiny bubbles in the fluid will coalesce after some time. A bleed the next day of 1-2 pumps per corner typically gets rid of them. If you do more pumps, you are putting more bubbles in the fluid. Granted, they will work their way back up into the reservoir or corner eventually but we don't need that if we don't have to.

If you have a problem that indicates there is air in the system, stop and find the problem. More bleeding isn't going to fix it. More bleeding just wastes time and fluid and will not ever solve a problem. Bleeding just gets air out of the system and if the above method doesn't do that, then the problem will not be fixed, found, or solved by doing more of it.

Last bit of annoyance I deal with frequently has to do with bench bleeding masters. If you could do it in the vehicle, it wouldn't be called bench bleeding. ;)
 
we still have the issue of not being able to seal straight threads at the bleed screw so even if the requirement was to have the hose in fluid to stop air from going into the caliper, it would still get in around the threads, it doesn't.

Thanks for sharing a qualified opinion Blaine. Isn't it amazing how many times folk lore overrides sound physics in the mechanical world.
I appreciate you .
 
Thanks for sharing a qualified opinion Blaine. Isn't it amazing how many times folk lore overrides sound physics in the mechanical world.
I appreciate you .

I'd be more comfy if you referred to it as qualified observation since it isn't my opinion, that's just how it works. I just paid attention to it, but yes, there is so much folk lore and mythology regarding the simple hydraulics that are a brake system, it is almost criminal. To this day we are still battling the ignorance that is a master "upgrade". A master upgrade doesn't exist. That isn't how it works. Master bore size is designed around piston area and booster output, nothing else.
 
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I'd be more comfy if you referred to it as qualified observation since it isn't my opinion, that's just how it works. I just paid attention to it, but yes, there is so much folk lore and mythology regarding the simple hydraulics that are a brake system, it is almost criminal. To this day we are still battling the ignorance that is a master "upgrade". A master upgrade doesn't exist. That isn't how it works. Master bore size is designed around piston area and booster output, nothing else.

Observation is a more appropriate word. And in hydraulics it's all about ratios and area . When it come to folk lore , the one I've dealt with is the " upgrade "
of wider brake drums and shoes stopping you so much better. Longer lasting , sure , but without increasing diameter , the leverage ratio remains unchanged
and the stopping power is unchanged.