Brake Issues

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DaveP
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Jeep Year: 2012
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Brake Issues

Unread post by DaveP »

I'm having some issues with a soft brake pedal that was really noticeable wheeling this weekend. With the engine off, I can pump the pedal and it gets firm. When the engine is on and I apply the pedal it goes all the way to the floor with little resistance.

To complicate troubleshooting, I just changed my rear pads and rotors this weekend. I have checked my brake fluid and it was low but above minimum. I am planning on bleeding my brakes to see if some air got in with the low fluid.

Would anyone be available this week to give me a hand double-checking this problem? Brake problems are new for me and I don't have a lot of experience here.
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Kurt
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Re: Brake Issues

Unread post by Kurt »

Dave,

Sounds like air in the brake lines. A thorough bleeding is in order. Being 4 years old it's a good time to flush the lines and bleed out the old fluid and put fresh in so be sure to have enough fluid on hand to do it.

I can give you a hand any day this week except Friday afternoon. Also available this Sunday thru next Friday.
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DaveP
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Re: Brake Issues

Unread post by DaveP »

Thanks Kurt. I sent a PM to plan a time to meet.
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pirahnah3
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Re: Brake Issues

Unread post by pirahnah3 »

I would def think air in the lines. Its easy to do accidentally when doing brake work.
'97 thats been chopped up and put back together, and ready to take on the trails.
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DaveP
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Re: Brake Issues

Unread post by DaveP »

Kurt and I bled the lines and a small amount of air from the front passenger line. The pedal was extremely soft after bleeding with no obvious leaks. We're thinking maybe a master cylinder problem? I did notice an air hiss when the engine turned off.

However, I drove home and the brakes felt better. The pedal felt firm when I pulled in the driveway. Not really sure what to think.
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MDSRACING398
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Re: Brake Issues

Unread post by MDSRACING398 »

On older stuff I have seen air get into master when low and gets trapped in there. On those you couldn't bleed it out without taking off because pedal doesn't full engage master cylinder. That's were bench bleeding comes into play. Not sure if issue if master is cheap enough i'ld start new but a thought
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DaveP
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Re: Brake Issues

Unread post by DaveP »

Confirmed that the master cylinder failed. I had it replaced today and it seems back to normal. Unfortunately, the shop said I have another project coming up because my all joints are failing. Ball joint wrench fest soon?
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Kurt
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Re: Brake Issues

Unread post by Kurt »

Bad MC... I thought that was the case. ;)
Ball joints are always fun. Need a good ball joint press to get them out.
Good time to get a loaner from Autozone or Advanced for the job when the day comes.
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pirahnah3
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Re: Brake Issues

Unread post by pirahnah3 »

Well glad you have the brakes figured out.

I gotta do ball joints myself before winter. Well those and a few other things lol.
'97 thats been chopped up and put back together, and ready to take on the trails.
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del_TJ
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Re: Brake Issues

Unread post by del_TJ »

I've used the Harbor Freight ball joint kit a couple of times and it works great.
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