Brake issues

[Frank Z]

I have one that fits the caliper...but it's too big for the brake line banjo.

:rattle:

 

[Frank Z]

Almost forgot....

Mega thanks to Joe and Led for the assistance today.

 

[techno1154]

I am happy you are making some progress,...one part eliminated. Now on to the others until the defected part show itself and is removed from the circuit. Good work guys.

 

[Led]

Almost forgot....

Mega thanks to Joe and Led for the assistance today.

I just like being around people that make me look cheerful:moon:

 

[Talyn]

Could the caliper have been leaking past the piston seal, but behind the dust boot?

 

[Frank Z]

Could the caliper have been leaking past the piston seal, but behind the dust boot?

Yep, that's about it.

A first for me....an invisible leak.

 

[Joe94xj]

Any luck? Or are you still tossing wrenches in the street?

 

[Frank Z]

Wrenches? Meh....I've progressed to Axles (D60's and 14bt) over the roof...overhand.

New calipers finally on....peddle still goes to the floor.

Laid under the rig while by better half handled the brake pedal and watched the lines again, both front and rear. I could see the front pistons slowly moving away from the rotors. grabbed my handy-dandy pocket flashlight and looked again.....and I saw it.

Seems the Braided SS. Brakelines don't have an adequate surface area to provide sufficient pressure on the copper washer between the banjo and the caliper.

I could see a hint of brake fluid seeping out from under the washer. as soon as the peddle was released the fluid would get pulled back.

Next step is to find some extended lines with a OEM Chevy banjo block.

 

[Joe94xj]

Getting closer. Sounds like you may have figured it out.

 

[Joe94xj]

The block end of your hose's are round correct? The ones i have are squared and seem a little bigger than yours if I am remebering right. You are welcome to try mine before you spend an more money. Wont be needing them for a few weeks.

 

[Frank Z]

Thanks for the offer Joe. I'm gonna hunt around for some Chevy lines until I get another SS set.

 

[Joe94xj]

Ok. If you cant find what your lookin for give undercar a call. They stock alot of brake stuff and have good prices.

 

[Digger87xj]

yet another problem of reman products. The brain surgeons sand blast the caliper so much they flatten the concentric sealing grooves that are supposed to circle the opening. Who knows how many times that caliper has seen the factory.

 

[Talyn]

What did you torque the banjo bolts to? They do require more than you would think to seal.

 

[Andy in Pa.]

If you get a set of SS lines with the square-ish banjos (like a lot of aftermarket SS lines have) just drill them out to the larger banjo bolt size. Thats what I did with mine and it worked perfectly.

 

[Frank Z]

New copper washers and new hoses....same old fading pedal.

Went to the carwash a few blocks from the house and gave brake system a serious hose-down. I'll get under it again later and look for leaks again.

 

[Frank Z]

I've been under, over, in, out, through, and around the entire system again...No leaks to be found anywhere. I clamped off both the front lines again and the pedal is rock solid after doing so.

I suppose the next option is to throw more money at it. Gonna try a new proportioning valve next. The current valve is from a ZJ that I installed when I did my rear disc conversion. It stayed put when I did my WJ coinversion, but now with Chevy calipers I'm having issues but I really am not certain that the Prop valve is at fault (yet that is).

I'm at my wits end and am simply out of ideas.

Any suggestions on a better option as far as prop valves are concerned?

 

[xj-grin]

Only that I don't think its your prop valve -- I ran those same Chevy calipers (waggy version) for years on the XJ with a stock 99 prop valve and no issues whatsoever (with rear discs as well).... Sorry I don't have any other ideas though - its been vac bled at this point?

 

[techno1154]

I clamped off both the front lines again and the pedal is rock solid after doing so.

How did you clamp them? By pinching the rubber hose or you use plugs in the master cylinder?

Go as close to the calipers as you could get and close the lines there,...just before the calipers.

 

[Joe94xj]

Frank are there any big bore master cylinder upgrades out there for the cherokee? I am wondering if your master cylinder might be to small for those calipers.