Brake Issues

User avatar
DaveP
BSJ Member
Posts: 57
Joined: Tue Mar 12, 2013 9:44 am
Jeep Year: 2012
Jeep Model: JK Wrangler
Location: Chelmsford, MA

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.
User avatar
Kurt
BSJ Member
Posts: 4207
Joined: Wed Dec 23, 2009 11:53 am
Jeep Year: 1992
Jeep Model: YJ Wrangler
Real Name: Kurt K.
Location: Pepperell, MA

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.
"Build It, Run It, Break It, Improve It, Repeat!"
NEA Treasurer 2016, 2017, 2018, 2019, 2020
BSJ Treasurer 2020
User avatar
DaveP
BSJ Member
Posts: 57
Joined: Tue Mar 12, 2013 9:44 am
Jeep Year: 2012
Jeep Model: JK Wrangler
Location: Chelmsford, MA

Re: Brake Issues

Unread post by DaveP »

Thanks Kurt. I sent a PM to plan a time to meet.
User avatar
pirahnah3
BSJ Member
Posts: 1317
Joined: Mon Jun 27, 2016 9:26 pm
Jeep Year: 1997
Jeep Model: TJ Wrangler
Real Name: Jim

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.
User avatar
DaveP
BSJ Member
Posts: 57
Joined: Tue Mar 12, 2013 9:44 am
Jeep Year: 2012
Jeep Model: JK Wrangler
Location: Chelmsford, MA

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.
User avatar
MDSRACING398
BSJ 101 Planning Commitee
Posts: 3294
Joined: Fri Feb 12, 2016 10:24 pm
Jeep Year: 1985
Jeep Model: CJ7
Real Name: Mark

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
Do it right the first time!
Second place is First Loser! Work Harder
Semper Fi
User avatar
DaveP
BSJ Member
Posts: 57
Joined: Tue Mar 12, 2013 9:44 am
Jeep Year: 2012
Jeep Model: JK Wrangler
Location: Chelmsford, MA

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?
User avatar
Kurt
BSJ Member
Posts: 4207
Joined: Wed Dec 23, 2009 11:53 am
Jeep Year: 1992
Jeep Model: YJ Wrangler
Real Name: Kurt K.
Location: Pepperell, MA

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.
"Build It, Run It, Break It, Improve It, Repeat!"
NEA Treasurer 2016, 2017, 2018, 2019, 2020
BSJ Treasurer 2020
User avatar
pirahnah3
BSJ Member
Posts: 1317
Joined: Mon Jun 27, 2016 9:26 pm
Jeep Year: 1997
Jeep Model: TJ Wrangler
Real Name: Jim

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.
User avatar
del_TJ
BSJ 101 Planning Commitee
Posts: 381
Joined: Thu Aug 26, 2010 1:19 pm
Jeep Year: 1998
Jeep Model: TJ Wrangler
Location: Newton, MA

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.
Post Reply