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Brake Bleeding

Grey5.0

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Hey,

This is the second time I've tried to bleed these brakes (pp1 package ) and can't get them tight. I like my brakes on the touchy side,when I first got the car they were super tight. Currently I can press my foot to the floor.

How I'm currently/have done/doing it.
Start passage rear, driver rear, passenger front, driver front.

Have someone in the car they pump and hold or pump pump hold. Twist valve see bubbles and turn off. Do that until no bubbles then move to the next one.

Every time I get done the car is exactly the same and if I start the process again there are always bubbles. Idk if I'm doing something wrong or what but I've gone through 4 bottles of fluid and still not tight.

I checked for leaks and there are none. The tank never goes under min.

I am doing this with the car running, any ideas what I'm doing wrong? The pads all look to have about a 1/4 plus on the backs. Rotors are smoothish for a 45k car.

I'm stumped, thoughts?
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Bad master, air in the ABS unit, leak......
 

paulm1

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yeah try it without the car running. Also, see if you can borrow, rent, buy a pressure bleeder. if you can bleed it with that and dont see any bubbles but the pedal is still soft it's the master.
 

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Grey5.0

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yeah try it without the car running. Also, see if you can borrow, rent, buy a pressure bleeder. if you can bleed it with that and dont see any bubbles but the pedal is still soft it's the master.
Like all the way off or on start? I have a bleeder but the came doesn't fit.
 

Dana Pants

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Your problem is super weird. Try bleeding with pressure:



You could also have bent/delaminating pads which also lead to squishy pedal.
 

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I have the power bleeder and it makes it much easier. You just need to buy the unit and the correct cap/adapter.

Then you fill the reservoir, pump it up to about 20 psi and crack open the bleeder valve and capture the fluid.

If you've done that and you're not getting voids or any spitting or sputtering, then as others have said, there's a defect somewhere in your system (either the master or possible leak somewhere).

A leak usually presents itself with visible fluid somewhere and/or the level on the reservoir drops slowly over time (as you pressurize with brake engagement it pumps out some fluid from the system).
 

NightmareMoon

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If you keep seeing bubbles, you need to get rid of those.

make sure the bleeder valves are tightened off while there is pressure and fluid coming out, that means during the press stroke on the pedal, otherwise theycan suck air back in.

i do recommend a pressure bleeder like the Motiv, makes it easier and you only need 1 person.

Also check the pads for glazing. If they’re glazed they won’t have that original bite feel, but if your foot goes to the floor thats probably an air in the lines problem.
 

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paulm1

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Another thing to check is to detach the master from the booster, just pull away a few mm and see if any fluid is back there. If so master is bad. Master could still be bad even if its dry there but its a quick thing to rule out.
 
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If you keep seeing bubbles, you need to get rid of those.

make sure the bleeder valves are tightened off while there is pressure and fluid coming out, that means during the press stroke on the pedal, otherwise theycan suck air back in.

i do recommend a pressure bleeder like the Motiv, makes it easier and you only need 1 person.

Also check the pads for glazing. If they’re glazed they won’t have that original bite feel, but if your foot goes to the floor thats probably an air in the lines problem.
you wouldnt have a link to the correct fitting for the top?
Another thing to check is to detach the master from the booster, just pull away a few mm and see if any fluid is back there. If so master is bad. Master could still be bad even if its dry there but its a quick thing to rule out.
Thanks Ill look at this as well, im assuming even with the car off I need to pump and hold or just pump?

Also while the brakes were being held, I did the passenger front and nothing came out, Now this is after I did the rears but I was trying to simply hold and bleed them to see if that would change anything. After i pumped them fluid/air came out.

Thanks again for all the quick responses.
 

galaxy

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you wouldnt have a link to the correct fitting for the top?


Thanks Ill look at this as well, im assuming even with the car off I need to pump and hold or just pump?

Also while the brakes were being held, I did the passenger front and nothing came out, Now this is after I did the rears but I was trying to simply hold and bleed them to see if that would change anything. After i pumped them fluid/air came out.

The car on or off has nothing to do with the fluid portion of the brakes. That's all hydraulics. The car running is only to provide vacuum to the booster for power at the pedal (in simple terms). You don't want the car running becasue 1) it's completely unnecessary and 2) no power to the booster provides better feel at the pedal while going through this process.

You will not get fluid coming out of a bleeder port while "holding" the pedal. The fluid in the whole system is statc. And what I mean by that is if the pedal is not actively moving, no fluid is moving. Even with a bleeder open, if the pedal is stationary, you should not have fluid or air gushing out. Maybe a trikle or so, but not flow. This is the same reason you do not want to release the pedal with a bleeder open. You'll suck air back in.

Sorry if it comes across as me mansplaining this to you, but with your statement about no fluid coming out while "holding" the pedal, I just wanted to make sure you're on the right page.
 

paulm1

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you wouldnt have a link to the correct fitting for the top?


Thanks Ill look at this as well, im assuming even with the car off I need to pump and hold or just pump?

Also while the brakes were being held, I did the passenger front and nothing came out, Now this is after I did the rears but I was trying to simply hold and bleed them to see if that would change anything. After i pumped them fluid/air came out.

Thanks again for all the quick responses.
So you never want to release the pedal with a bleeder open. The person in the driver seat. Should pump the pedal a couple times then press and hold the pedal with significant pressure. Eg. If i have my wife help me i tell her to use both feet. The key is to not release pressure on the pedal until you open and then close the bleeder valve. If the person helping you releases that pedal while you have the bleeder open you just let air back in the system. The pedal is going to travel down when you open the bleeder, the key is not to relese the pedal until you close the bleeder. This requires good communication harder to hear with the engine running. Capice?
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