Lots of Bleeding

[rkcbvw]

I tried searching for solution and i know this has been discussed but I am pulling my hair out on this: I have been working on a cj build (almost 2 years now) and feel like I am spending way too much time trying to get my brakes to bleed. I have put 3-4 big bottles of fluid trying every method I can think of (2 person, 1 man check valve, gravity feed etc). FYI I have swapped master cylinder from cherokee which was working in my 1980 cj fine. This winter I replaced a front caliper and brake lines. Since then I cannot get them to bleed. Pedal goes to floor even without running motor. I bled mc, I have since tried plugging ports on mc and pressure is firm with ports plugged. Makes me think MC is ok..?? I bled brakes all the way around many many times now. I lift each tire with brakes applied and I can turn every wheel by hand with only slight amount of resistance. Seems like if I have a wheel cylinder out either front or back would hold ok. What am I missing or what should I check?

 

[Lumpy Grits]

Get a new MC and pressure bleed.
LG

 

[rkcbvw]

When I plugged the MC I threaded 2 fine thread bolts into the ports finger tight. When I pumped my brakes they were firm plus fluid squeezed out past the threads of the bolts. Wouldnt this rule out my MC as problem or do you still think that is it? I do have to admit the MC did sit for 5 or 6 months mostly empty of fluid.

I also do not have a proporsioning valve could this be my problem?

 

[Posi]

This winter I replaced a front caliper and brake lines. Since then I cannot get them to bleed.

Did you install the calipers on the correct side so the bleeders are at the highest point? If you didn't it wouldn't be the first time that happened.

 

[rkcbvw]

they are both facing up.

 

[Hedgehog]

You are pulling air past something in the system, likely a bleeder or more likely the fitting. I'd bet its a fitting very close to the master cylinder. The thing simply can't build pressure.

 

[rkcbvw]

thanks, I will look.

 

[Lumpy Grits]

Is this M/C of yours, the correct PN for what you have it in?
What jeep is it in?
LG

 

[Hedgehog]

Something else I just thought of. All Master Cylinders are not made the same. Yours might not be pushing enough brake fluid to run the brake set up your jeep requires. I am beginning to think it would be wise to purchase the correct part for your jeep rather than guess about what might be wrong. It appearse that you've given it about as good a try as you can.

 

[mtnwhlr]

Why are you putting a MC for a Cherokee on your CJ? You said it sat dry for some time did you bench blead it before installing it?

 

[rkcbvw]

Why are you putting a MC for a Cherokee on your CJ? You said it sat dry for some time did you bench blead it before installing it?

I used the mc to add power brakes to my cj which has worked great. I used the existing mc/booster for over a year and then decided to start the jeep rebuild which was reason the mc sat for 6 months. The only thing that has changed since my rebuild is a new brake caliper on front drivers wheel. Thanks for suggestions.

 

[hole]

Try bleeding the fronts first, then rear, then finish with fronts again.
http://www.jeep-cj.com/forums/f19/what-proper-way-12118/?highlight=bleeding+brakes

 

[Posi]

I have since tried plugging ports on mc and pressure is firm with ports plugged.

I was going to suggest you cap the MC but I see you already have. This would lead me to believe the MC is working as it should.

I also do not have a proporsioning valve could this be my problem?

My first thought would be no, because the prop valve just meters the fluid delaying the front brake action. I will give this some more thought
Although the method Hole suggests is for Jeeps with a prop valve I would still give it a try. Please post your results.

 

[Posi]

What are you running disc/disc, disc/drum?

 

[rkcbvw]

What are you running disc/disc, disc/drum?

Disc/drum.

 

[rkcbvw]

thanks for your help guys, I decided to take each wheel off again and look things over and found that I was given wrong caliper. I have 2 rights. When I checked before my bleeder was on top for both sides and my right side banjo was on top but I did not notice the banjo on my left was on bottom. rigged/flipped it to test and brakes hold rock hard. Thanks again.

 

[Posi]

Good to hear you found the problem, like I mentioned it wouldn't be the first time that happen.
If your running disc/drum you should be running a prop valve as well, summit sells the self adjusting ones.

 

[rkcbvw]

Good to hear you found the problem, like I mentioned it wouldn't be the first time that happen.
If your running disc/drum you should be running a prop valve as well, summit sells the self adjusting ones.

thanks for the advice.