Brakes going soft after raising car?

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I don't know why I posted "would not lubricate". Of course I mean I would. Gettin more stupid I guess.
 
I adjusted the rear brakes, 2 clicks on each side. Made the pedal feel more firm thats for sure... I also raised my front drivers side to adjust my transmission and what do you know... if feels like I got air in it again :mad::BangHead::wtf: good news, transmission feels better, brake pedal is higher but bad news is I will bleed them again... I will also tighten the lines to ensure the fittings are slipping ever so slightly allowing air to get in.

We are at the park again so it'll happen later tonight and I probably won't be able to drive the car after because it will be to late.

Question- I've done it both ways (with help from wife) when you all bleed your brakes do you press the pedal and open bleeder. Or do you pump the pedal 3x before opening the bleeder?
 
Sounds like you have some air trapped in the system that keeps getting up to the master cylinder when you jack the car around.
 
Sounds like you have some air trapped in the system that keeps getting up to the master cylinder when you jack the car around.

Yeah thats what I am thinking as well, I dont know how to get it out though. I've literally bled the brakes so many times. But most of the times the system was bled was before I made and installed the new brake lines. I guess I have multiple jobs on the car this week...
 
Yeah thats what I am thinking as well, I dont know how to get it out though. I've literally bled the brakes so many times. But most of the times the system was bled was before I made and installed the new brake lines. I guess I have multiple jobs on the car this week...

Maybe put the front of the up on stands and remove the master cylinder cap and let it sit a few days.
 
Raising front end to get air to top may work. Leaving cap off? Rob i disagree. Brake fluid absorbs mousture from the air.

when i bleed brakes, i use a pedal depressor and do it myself. One pump,lock pedal down and open bleeder
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Many many times i just gravity bleed. No pedal action whatsoever. Cap off and keep resevoir full. One bleeder at a time. Two or three minutes per bleeder, and i watch closely for bubbles. I just refill between closing and opening next one.
 
Left front. You get air immediately? Reason i ask is to determine if air is in caliper or up the line somewhere. calipers, in front or drum brakes. I dont recall.
 
Raising front end to get air to top may work. Leaving cap off? Rob i disagree. Brake fluid absorbs mousture from the air.

when i bleed brakes, i use a pedal depressor and do it myself. One pump,lock pedal down and open bleeder View attachment 1715635306

Although air is not "in the system" normally, there is air between the cap and top of the fluid in the master cylinder. There is also a vent in the master cylinder cap. The cap is there only to keep fluid from spilling out, it's not an air tight system. That's not how it works. I do agree brake fluid does absorb moisture. But it's designed to. At least everything but DOT5. Were it not for fluid sloshin all over the place, you could throw the masted cylinder lid in the ditch and go.
 
Left front. You get air immediately? Reason i ask is to determine if air is in caliper or up the line somewhere. calipers, in front or drum brakes. I dont recall.

That pedal depressor is nice, I've used my syringe bleeder before and it worked pretty well. I've also gravity bled my brakes before as well, the only problem with that is the rears barely gravity bleed at all.

I have front discs and rear drums.
 
Although air is not "in the system" normally, there is air between the cap and top of the fluid in the master cylinder. There is also a vent in the master cylinder cap. The cap is there only to keep fluid from spilling out, it's not an air tight system. That's not how it works. I do agree brake fluid does absorb moisture. But it's designed to. At least everything but DOT5. Were it not for fluid sloshin all over the place, you could throw the masted cylinder lid in the ditch and go.
Its air tight enough. Alcohol base fluid, will take on moisture.
Most master cylinder boots are designed to drop with the fluid,vent in cap is to allow air in above the boot, designed to work like a bellows.
 
That pedal depressor is nice, I've used my syringe bleeder before and it worked pretty well. I've also gravity bled my brakes before as well, the only problem with that is the rears barely gravity bleed at all.

I have front discs and rear drums.
3/8” round bar,steel platd with a 3/8 hole. Knob is to push on. wedge plate against front of seat. Easy.
 
Its air tight enough. Alcohol base fluid, will take on moisture.
Most master cylinder boots are designed to drop with the fluid,vent in cap is to allow air in above the boot, designed to work like a bellows.

I agree, but still it's not air tight as far as moisture. That's the whole reason for recommended brake fluid changes, because it gets contaminated over time. It won't hurt a thing to leave the cap off a day or two. He can put a shop cloth over it if he's skiddish.
 
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Put car on all four jack stands, jack up the front of the car all the way up higher than the rear. Then bleed the rear should way a good squirt of fluid coming out. If you wanna do it with a vacuum bleeder, attach the vacuum bleeder to the bleeder screw while it’s shut, then pump up to 25 inches and crack open the bleeder screw so you can pull all that air out. If that doesn’t help you need to blow the lines out and master cylinder, then bleed the master cylinder first then the brakes you might have some sediments in the rear lines.
 
Put car on all four jack stands, jack up the front of the car all the way up higher than the rear. Then bleed the rear should way a good squirt of fluid coming out. If you wanna do it with a vacuum bleeder, attach the vacuum bleeder to the bleeder screw while it’s shut, then pump up to 25 inches and crack open the bleeder screw so you can pull all that air out. If that doesn’t help you need to blow the lines out and master cylinder, then bleed the master cylinder first then the brakes you might have some sediments in the rear lines.


The the lines are brand new. I may been again in a couple of days... the car isn't moving right now as the front of it is taken apart...
 
The the lines are brand new. I may been again in a couple of days... the car isn't moving right now as the front of it is taken apart...
How are they bent? Kind of like the factory style? Of were the hand bent etc.
 
How are they bent? Kind of like the factory style? Of were the hand bent etc.

I made them with steel line and bent them with a brake tube bender to mirror factory (as much as I could). The picture of the fittings, all of the flares look like the middle and one on the left. I ended up buying a flare tool to make better flares, that picture shows store bought (left), flares with new tool (middle) and flares with cheap rentals (right)

The only things not new in the brake system is the prop valve and lines from MC to prop valve. I got the prop valve locally from someone. Traded my stock distribution block for his prop valve...

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I made them with steel line and bent them with a brake tube bender to mirror factory (as much as I could). The picture of the fittings, all of the flares look like the middle and one on the left. I ended up buying a flare tool to make better flares, that picture shows store bought (left), flares with new tool (middle) and flares with cheap rentals (right)

The only things not new in the brake system is the prop valve and lines from MC to prop valve. I got the prop valve locally from someone. Traded my stock distribution block for his prop valve...

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I was going to ask if you used a double flare on those lines. The one on the right looks like a single flare and for brake systems that is bad. That flare won’t hold up under brake line pressures and it will fail. Then you’ll have a big poop sandwich on your hands.
 
It's a pain, and brake fluid and paint don't get along well. It's possible that your rebuilt master cyl is defective. That happened to me last year, caught it when bleeding the master, metal debris in fluid. Start over with rebleeding the master, then the lines. If your problem persists keep looking, a leaky master may not show immediately, but you will not like what the brake fluid does to your firewall! Just looking at all connections is sometimes not enough, run your finger over it, make sure they are all dry.
You may need to replace the emergency brake cable if it is sticky and will not free up with oiling the entire casing front to rear. Your choice, rust blaster first, then oil.
Don't know if they are still available, but one of these is nice for rear ballpark adj.
Good Luck, nice Dart.
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@DentalDart did you ever get the problem figured out and get all the air out of the system?

Really I'm not quite sure. I haven't bled it in a while a the brakes are holding up nicely for the past couple of months, granted I haven't been driving it much. I did however buy all new calipers, pads, master cylinder and little parts to replace all that stuff.

I got some new aluminum heads and figure I may redo the entire brake system with rear disc's when I have a new motor built for the car.
 
Really I'm not quite sure. I haven't bled it in a while a the brakes are holding up nicely for the past couple of months, granted I haven't been driving it much. I did however buy all new calipers, pads, master cylinder and little parts to replace all that stuff.

I got some new aluminum heads and figure I may redo the entire brake system with rear disc's when I have a new motor built for the car.
I’m in a similar situation. Ive bled my brakes twice now and the pedal still isn’t very good. Now, I have 13” cobra brakes on the front so a different designed caliper than you have but similar symptoms. I think I might order a Motive pressure bleeder and bleed it that way.
 
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