Cannot get brakes to bleed

[mrblaine]

Blaine,

I apologize, I’ve learned to be weary of terms like left and right or front or rear since some idiot like myself could mix them up flange size is impossible to mix up. I’ll start with the rear and give it a whirl, I appreciate your help greatly!

I am nothing if not accurate. There is only one front, one rear, one left, and one right. The lights tell the whole story for the directionally impaired. The tests are very simple.

Flip your turn signal to indicate a left turn. Now get your ass out of the seat and go see which side of vehicle the little lights are blinking on. That is the left side. Repeat the test for the right side. If you can't remember it, write it down on a cheat sheet and carry that with you at all times while driving.

Get a short stick long enough to go between the front of the seat and the brake pedal. Use that to push down the brake pedal and walk around the rig until you find the brake lights that are illuminated. That is the rear of the vehicle.

Take the stick out and toss it unless you forgot to write down which end is the rear of the vehicle. Turn the head lights on. Get out, walk around the rig and find the end that is lit up by the biggest white emitting lights. That is the front of the rig.

You can do the front and rear identification with the transmission. Put it in drive or first gear, ease into the throttle or ease out the clutch and ease into the throttle to see which way the vehicle moves. That is forward, that also means the end that will smack something first while moving forward is the front.

 

[Dave.R]

I am nothing if not accurate. There is only one front, one rear, one left, and one right. The lights tell the whole story for the directionally impaired. The tests are very simple.

Flip your turn signal to indicate a left turn. Now get your ass out of the seat and go see which side of vehicle the little lights are blinking on. That is the left side. Repeat the test for the right side. If you can't remember it, write it down on a cheat sheet and carry that with you at all times while driving.

Get a short stick long enough to go between the front of the seat and the brake pedal. Use that to push down the brake pedal and walk around the rig until you find the brake lights that are illuminated. That is the rear of the vehicle.

Take the stick out and toss it unless you forgot to write down which end is the rear of the vehicle. Turn the head lights on. Get out, walk around the rig and find the end that is lit up by the biggest white emitting lights. That is the front of the rig.

You can do the front and rear identification with the transmission. Put it in drive or first gear, ease into the throttle or ease out the clutch and ease into the throttle to see which way the vehicle moves. That is forward, that also means the end that will smack something first while moving forward is the front.

Thanks for the clarity. If only we could always work on the Jeep from the drivers seat.

 

[qslim]

@mrblaine would have made a great military drill instructor.

 

[Dave.R]

After turning on my Jeep and oriented it pointing north, I was able to remove the master cylinder and bled the southern most port (I’m in the northern hemisphere) first, and then the Yankee northern port after that and it worked well.

Still seems a touch soft but I was able to get the MC to 1/8 of an inch, If measured from the white headlight to red taillight direction.

Thanks for all the help.

 

[mrblaine]

After turning on my Jeep and oriented it pointing north, I was able to remove the master cylinder and bled the southern most port (I’m in the northern hemisphere) first, and then the Yankee northern port after that and it worked well.

Still seems a touch soft but I was able to get the MC to 1/8 of an inch, If measured from the white headlight to red taillight direction.

Thanks for all the help.

Happens with those parts. They are barely better than stock but they have great marketing.

 

[Dave.R]

Happens with those parts. They are barely better than stock but they have great marketing.

I knew it was mostly hype, just was a convenient kit till I ordered your 17 inch gig later this year.

 

[Dave.R]

Took the LJ out tonight to compare, and with that I can't get the pedal to the floor at a stand still and especially while driving. The TJ stops damn well, but takes almost all the pedal to do so. I'm going to try to bleed the MC again and swap it, but something I noticed yesterday that I thought I'd run by the brake God, When the pedal comes back up, there is a slight moo? sound. Kind of sounds like those old toys you'd flip over and they'd moo.


When I did the MC yesterday, I ran the plunger until fluid was at both ports, plugged them, cracked the rear, compressed, and tightened the plug a few times till I had a steady fluid stream. Then did the front in the same manner, and then pumped the plunger up until I could only move the plunger about 1/8 or so.

I'm not entirely sure how to know when I'm done bleeding the ports without being able to see the bubbles.

Sorry for all the questions, trust me, I'm sick of it too. I would think it was a problem with the calipers, but they are just stock replacements.

 

[mrblaine]

Took the LJ out tonight to compare, and with that I can't get the pedal to the floor at a stand still and especially while driving. The TJ stops damn well, but takes almost all the pedal to do so. I'm going to try to bleed the MC again and swap it, but something I noticed yesterday that I thought I'd run by the brake God, When the pedal comes back up, there is a slight moo? sound. Kind of sounds like those old toys you'd flip over and they'd moo.

Not sure what causes that sound but if mine was doing it, I'd be looking at replacing the booster. Can you lock up the front tires?

When I did the MC yesterday, I ran the plunger until fluid was at both ports, plugged them, cracked the rear, compressed, and tightened the plug a few times till I had a steady fluid stream. Then did the front in the same manner, and then pumped the plunger up until I could only move the plunger about 1/8 or so.

I'm not entirely sure how to know when I'm done bleeding the ports without being able to see the bubbles.

Sorry for all the questions, trust me, I'm sick of it too. I would think it was a problem with the calipers, but they are just stock replacements.

If you got it to where the plunger only goes in the eighth or so, it is bled.

 

[Dave.R]

Not sure what causes that sound but if mine was doing it, I'd be looking at replacing the booster. Can you lock up the front tires?

If you got it to where the plunger only goes in the eighth or so, it is bled.

The road was damp yesterday, and I have no problem getting the front end to lock and skid, but it takes most of the pedal to do so. When stopped I can get it to the floorboards if I push pretty hard, my other jeep (LJ) I can only get about half way down.

I would suspect the booster more, but when the Jeeps off, it's a super firm pedal I can't get to the floor, and when it's on is when it's soft. So I would have thought the BB is still working. But it's about the only thing I haven't replaced yet. What started all of this was sticky calipers that I decided to replace, the MC and BB were working fine previously.

After the MC was bleed I plugged the ports till I was just ready to install and then hooked up the lines, am I somehow letting air back in then? I had considered having my wife hold down the pedal as I hooked up the lines, but I was worried that might suck air into the MC from the top of the lines.

 

[Kid Mechanic]

Sounds as if you just need to go back through the bleeding pattern for the calipers.

I bleed brakes by myself with a tube in a jar method. Get your wife to help with pedal, it will make it as though she saved the day and you will be in her debt forever.

 

[mrblaine]

The road was damp yesterday, and I have no problem getting the front end to lock and skid, but it takes most of the pedal to do so. When stopped I can get it to the floorboards if I push pretty hard, my other jeep (LJ) I can only get about half way down.

I would suspect the booster more, but when the Jeeps off, it's a super firm pedal I can't get to the floor, and when it's on is when it's soft. So I would have thought the BB is still working. But it's about the only thing I haven't replaced yet. What started all of this was sticky calipers that I decided to replace, the MC and BB were working fine previously.

After the MC was bleed I plugged the ports till I was just ready to install and then hooked up the lines, am I somehow letting air back in then? I had considered having my wife hold down the pedal as I hooked up the lines, but I was worried that might suck air into the MC from the top of the lines.

No, you aren't letting air back in since fluid is running out.

 

[Dave.R]

Sounds as if you just need to go back through the bleeding pattern for the calipers.

I bleed brakes by myself with a tube in a jar method. Get your wife to help with pedal, it will make it as though she saved the day and you will be in her debt forever.

I feel like I've bleed the hell out of them. I've read Blaine say 5-7 pumps is all you should need per corner. I'm going to try that again today and hopefully get it.

My process is RR-LR-RF-LF - Open the bleeder, have her put the pedal to the floor, lock the bleeder, let the pedal up, and then she spikes the pedal once to reset the light, and we do it all over again. The first time we do it we seem to get a bubble or two, but only the first time till I'm running solid liquid.

 

[mrblaine]

I feel like I've bleed the hell out of them. I've read Blaine say 5-7 pumps is all you should need per corner. I'm going to try that again today and hopefully get it.

My process is RR-LR-RF-LF - Open the bleeder, have her put the pedal to the floor, lock the bleeder, let the pedal up, and then she spikes the pedal once to reset the light, and we do it all over again. The first time we do it we seem to get a bubble or two, but only the first time till I'm running solid liquid.

When you do it again, only do 2 pumps per corner to get the last little bubble out. If you do more, you are putting more air back in since the master aerates the fluid during bleeding.

 

[Kid Mechanic]

Pump a couple time, hold. Unlock bleeder, pedal goes to floor, lock bleeder.

If you are getting a soft pedal there is a leak. Some times you need to rotate a new caliper to get trapped are out by removing from bracket. Bang it with a rubber mallet to dislodge trapped air. All kinds of tricks when putting on new stuff.

edit; I forgot, don’t let the pedal go all the way to the floor, just close. Again, brain a little rusty.

 

[mrblaine]

Pump a couple time, hold. Unlock bleeder, pedal goes to floor, lock bleeder.

If you are getting a soft pedal there is a leak. Some times you need to rotate a new caliper to get trapped are out by removing from bracket. Bang it with a rubber mallet to dislodge trapped air. All kinds of tricks when putting on new stuff.

Awesome, you just put more air in the fluid.

 

[Dave.R]

When you do it again, only do 2 pumps per corner to get the last little bubble out. If you do more, you are putting more air back in since the master aerates the fluid during bleeding.

I will give that a try. I did notice occasionally I don't get a bubble but rather a "aerated" looking section maybe an inch long. That might be the air getting whipped into it like you're talking about.

 

[mrblaine]

I will give that a try. I did notice occasionally I don't get a bubble but rather a "aerated" looking section maybe an inch long. That might be the air getting whipped into it like you're talking about.

That is exactly what it is. Modern masters fairly well suck in that regard. The small bubbles will be present throughout the fluid. It is impossible to get them out with a manual bleed. We do the bleed, then the next day do a 1-2 pop per corner to get the rest after the small bubble coalesce into one larger bubble in each caliper.

 

[Kid Mechanic]

Please

Awesome, you just put more air in the fluid.

Please explain. I’m always ready to learn more.

 

[hosejockey61]

FWIW I had that moo sound in another vehicle and it was the brake booster.

 

[mrblaine]

Please

Please explain. I’m always ready to learn more.

One pedal pump with the bleeder open or closed entrains very small bubbles into the brake fluid. Doing several just ensures that you wind up with them in the fluid in all the lines faster. They eventually settle out but you can not get rid of them in the first bleed. If you watch the fluid closely in a clear line, the big easy to see bubbles go away quickly in a few pumps per corner. If you continue, then what you will see is the fluid with 100's of very tiny bubbles start to come out. You can pump the master dry and they won't stop, they have to settle and then get bled out.

I've bled the brakes on 100's of TJs. Not once have I done so that I did not get a couple of small bubbles out of each corner. I made it a habit to start checking every TJ I worked on just to see. None did not have a couple of small bubbles at each corner. That is when I really started paying attention and doing the couple of pumps after the tiny bubbles settle out.

Pumping the pedal with the bleeder closed only makes it worse.