Air in brake line

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JG510

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I have a 2007 Yukon SLE 4.8L v8. I bled my brakes the other day because I wanted to flush out old fluid. I did the 2 person method, one person pumps 3 times, while leaving pedal on the bottom, second person opens bleeder then closes bleeder and repeats. I started with the right rear side then left rear, and everything was going good. As soon as I opened the front right bleeder valve, a lot of air came out and now the brake pedal drops to the floor. any suggestions on how I can fix this?
 

RST Dana

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I have a 2007 Yukon SLE 4.8L v8. I bled my brakes the other day because I wanted to flush out old fluid. I did the 2 person method, one person pumps 3 times, while leaving pedal on the bottom, second person opens bleeder then closes bleeder and repeats. I started with the right rear side then left rear, and everything was going good. As soon as I opened the front right bleeder valve, a lot of air came out and now the brake pedal drops to the floor. any suggestions on how I can fix this?

Refill master cylinder and repeat?
 

Rocket Man

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The pedal should never be allowed to go all the way to the floor or you'll damage the master cylinder. Most people put a piece of wood down so that doesn't happen or just make sure the person closes the bleeder before that happens. Sounds like at the least you need to bleed the master and start over. I use a Motive pressure bleeder and it's so easy to bleed brakes it's crazy. You might look into one.
 

Meccanoble

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I'm thinking some air snuck in through the process. Best to try again. Remember to follow correct order of wheels and make sure that bleeder is closed before pedal come sback up.
 

Trailblazzin

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The pedal should never be allowed to go all the way to the floor or you'll damage the master cylinder. Most people put a piece of wood down so that doesn't happen or just make sure the person closes the bleeder before that happens. Sounds like at the least you need to bleed the master and start over. I use a Motive pressure bleeder and it's so easy to bleed brakes it's crazy. You might look into one.

I replaced both front calipers and during the process of bleeding, my "helper" unknowingly pressed the pedal to the floor multiple times. Is my master shot? My pedal is no longer firm, it is spongy when driving.
 

Rocket Man

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I replaced both front calipers and during the process of bleeding, my "helper" unknowingly pressed the pedal to the floor multiple times. Is my master shot? My pedal is no longer firm, it is spongy when driving.
Most likely. If bleeding them again doesn't fix it then you'll know the answer for sure. If you're going to bleed them that way, put a piece of 2 x 4 on the floor so it can't happen again.
 

Trailblazzin

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Most likely. If bleeding them again doesn't fix it then you'll know the answer for sure. If you're going to bleed them that way, put a piece of 2 x 4 on the floor so it can't happen again.

Sorry not trying to hijack this thread but wanted to get back with my results. So far so good, I was able to use a vacuum bleeder and get out all the air and the pedal firmed up and all seems good.
 

Walrusmt

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It's like you were living my life lol. Exact same thing happened to me - I'm heading into the drive to follow the process again, this time with a different helper. Hopefully my results are as good as yours.
 

Scottydoggs

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i bet the master went dry, once you get air in the master the rest wont bleed right.

them power bleeders can push that out.

if you dont have one, have your helper pump the pedal, then crack the lines off the master, you'll hear air spit out, do both lines. line stated, snug the line back up before the pedal pusher lets it up. pump, repeat till no air spits out.
 

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