Brake Bleeding???

icanfixall

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I understand we go to the farthest point from the master cylinder and work back from there but. When do I do the anti lock cylinder under the drivers seat area. Before or after doing the rear cylinders. Thanks all.
 

icanfixall

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Well now thats an ambiguous answer Russ. i will see what happens when I do this mess. Been having a low peddle and then a hig normal peddle. Finally located some wetness on right rear tire inside. Removed wheel and found brakes dry but a wetness under back side of wheel cylinder. New brakes installed about 2 months ago and this wheel cylinder was replaced. Will replace it again and hope for better replacement part... Sure glad the brakes are dry. I did save the other shoes because they were in good shape. Plenty of material left before the rivets were dragging.
 

chris142

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dont pump the pedal.... push down once,hold,open bleeder,close bleeder.release pedal. repeat as needed
 

icanfixall

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Thanks for the help guys but I need to ask why push down on the peddle once and hold??? What I found was a wheel cylinder had failed and this is after just replacing the rear brake shoes. Funny part was the shoes on that side were fine. No brake fluid on that at all. The leak was on the back side of the cylinder and not much of a leak either. I really had to look closely for it. Once I got the cylinder off it was more evident it was a leaker. Very little if any fluid drained out of the line too but sure had plenty of air bleeding out later. The hydroboost master cylinder has the large reservoir so it tuff to drain it when bleeding. That makes it easier for me. I don't have to keep checking it. Getting up and down it really ******* my body now. I do recall when it was easy to stand from laying under anything. Now I have to plan how I'm getting up. Which way will hurt the least. Brake peddle is firm and right at the top but the parking brake is still very low. Russ, I saw what you posted about the shoes needing more metal so the parking brake lever can actuate them at the top. Don't know what I will do about this problem. I really like a parking brake to work and work well.
 

4x4manonbroke

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You push down and hold to get the "Air Bubbles" to move out of the system, if you just pump if and then go bleed, your not doing anything .. I use a small 2x4 place it between seat and the brake pedal.. I did my truck alone, brakes work just fine ...

If you need to "Pump" the brakes, you could be Cavitating the brake fluid... refrain from pumping, it will make it harder to get a good brake pedal.

push down, bleed screw, release pedal wait for pedal to rise(Dont pull up ) repete as needed..
 

ironworker40

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rear antilock valve

I understand we go to the farthest point from the master cylinder and work back from there but. When do I do the anti lock cylinder under the drivers seat area. Before or after doing the rear cylinders. Thanks all.

According to the Ford service manual, bleed antilock valve after bleeding rears, and before fronts. I Have always done this since I owned my first 1987 f 250 that I bought new. I don't ever remember getting air out of antilock valve on any truck I have worked on.

Do you have that sinking brake pedal that most of these trucks have? I have read that it is caused by the antilock valve bypassing. I chased that condition years ago thinking it was the master, then thought I had a bad "new" master so I changed that one, then I changed the antilock valve. It cured it for a period of time but eventually came back. I have owned and driven several of these trucks from 1985-1997 model years and some do it and some don't. Has anyone cured this problem?
 

icanfixall

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The sinking brake peddle is from the rear shoes being way out of adjustment because the self adjusters wont work as designed. So the fronts do all the stopping. Whats happening is the peddle sinks as the master cylinder tries to fill the rear cylinders. Keep the reas manually adjusted and your fine. modifying the system to hydroboost changes all this. The 1 5/16 bore master cylinder is able to supple enough fluid to the out of adjustment rear cylinders.
 

chris142

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most people do it wrong. they pump and pump then bleed. spend all day bleeding and gallons of fluid lol
 

franklin2

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most people do it wrong. they pump and pump then bleed. spend all day bleeding and gallons of fluid lol

You can pump in the beginning when starting out with a dry system, it won't hurt anything as long as the bleeders stay closed. The master keeps adding and adding fluid to the system till you can get just a little bit of pedal, then you can open the bleeder and start making progress. I agree, I would not pump toward the end of the procedure, but sometimes you have to pump in the beginning to get things started.
 

Black dawg

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you shouldnt have to pump the pedal at all, gravity bleeding works 99% of the time, and then if there is still trapped air running the pedal works.
 

79jasper

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I like the speed bleeders.
I don't really pump them at all. Down, rest a second, up, rest, repeat.
A pressure bleeder would be best.
I like the first and last on the rabs, makes sure it's all out.
Now I've heard with out masters, we should release the bleeder before squeezing the piston back in because in can do damage to the piston cups in the master. Is that a possibility?
I know for abs cars you can foul the system doing that.

Sent from my SM-G900R4 using Tapatalk
 

franklin2

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Now I've heard with out masters, we should release the bleeder before squeezing the piston back in because in can do damage to the piston cups in the master. Is that a possibility?
I know for abs cars you can foul the system doing that.

Yes, someone in the know told me that also about the newer cars and trucks. Pushing the piston back pushes all that old rusty fluid back up in the complicated abs valve system and can cause it to fail. After I was told that, I started to also do it on these older trucks. It's doesn't hurt the master, but our systems can also do without all that rust being pushed back up in the system, and also if you keep the master topped off, it will overflow and make a mess unless you release the bleeder and let the excess fluid come out there. By the time you do that, and then bleed them a little bit from the master, you should have mostly new fluid in the system, getting rid of that old stuff.
 

oregon96psd

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Yes, someone in the know told me that also about the newer cars and trucks. Pushing the piston back pushes all that old rusty fluid back up in the complicated abs valve system and can cause it to fail. After I was told that, I started to also do it on these older trucks. It's doesn't hurt the master, but our systems can also do without all that rust being pushed back up in the system, and also if you keep the master topped off, it will overflow and make a mess unless you release the bleeder and let the excess fluid come out there. By the time you do that, and then bleed them a little bit from the master, you should have mostly new fluid in the system, getting rid of that old stuff.


If you've got rust in your brake system your gonna have bigger problems than possibly messing up a rabs valve...
 

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