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anthonyh75
01-18-2005, 01:51 PM
Ok my brakes never have worked all that well. I only have 265/75/16 tires on so im not trying to stop 33's or anything. My 96 zj had the same size tires on it and it stopped well enough. I replaced the MC and now my the truck doesnt start to slow down until the peddle is almost all the way to the floor. I tried bleeding the brakes wich didnt help much. I did read from searching that you cant pump the breaks to gain preassure as this can create smaller air bubbles. That may be part of my problem. I tried bleeding the brakes again and replaced my pass rear caliper (Bleeder valve stuck). Still the peddle goes all the way to the floor. I then replaced the porportioning valve. It seemed that I wasnt getting good preassure to the rear brakes. Still the peddle goes almost all the way to the floor. I know I must be missing something stupid. Any suggestions or help would be great. Thanks

MaineZJ
01-18-2005, 02:07 PM
first guess, air up by the MC

JpRngr
01-18-2005, 03:53 PM
Did you bench bleed the MC before installing it? If you didn't, your MC probably still has a butt load of air in it.

To bench bleed, you mount the MC in a vise, install bleeder tubes in the outlet ports fed into the reservoir. With the reservoir full of fluid, pump the input rod until all signs of air have stopped coming out of the ports.



Corey

anthonyh75
01-18-2005, 04:38 PM
Yeah I bench bled the MC. I thought the new MC may have been bad as well so I took it back and replaced it with another one. I was careful to fully bench bleed the new one before putting it back on. It does seem like a problem with air. I had decent peddle before I tried to fix all of this. The truck just didnt seem to stop very well. I couldnt lock up the brakes no matter what speed I was going. Well not even enough to kick on the abs. Any other ideas guys? Is there any adjustment for the throw of the peddle or plunger that goes into the MC. It just seems like there is air or that the new MC isnt engaging soon enough. The brakes seem to work but not until the peddle is about an inch from bottoming out. Thanks again

JpRngr
01-18-2005, 09:35 PM
Does the pedal feel normal, just very low? Or does it feel like there's resistance on the pedal before it firms up? If it feels like there's just a bunch of free travel before it gets down to where it engages, I would bet the new MC's pushrod is different. Do you still have the old MC that you could compare it with? If it has some resistance but doesn't build enough until the pedal's low, you have air somewhere.

Corey

anthonyh75
01-19-2005, 10:09 AM
The peddle has almost no resistence until it is almost all the way to the floor then it firms up pretty good and the brakes work pretty good. I think it bottoms out on the floor before I can actually get full brake preassure. The MC looked the same although I dont have the old one anymore to compare. I replaced a MC on a older F350 and the power booster had any adjustment on it for the amount of throw needed for the push rod. Does anyone know if the booster on the zj has any ajustment?

anthonyh75
01-20-2005, 09:35 AM
Ok I finally have good brake preassure. Bleed the hell out of the brakes yesterday and for some reason bleeding with the MC cap off helped. I still dont have all that great of stopping power with the new MC, one new Caliper, New Porportioning valve, New brake fluid, Any other ideas other than going with the kung Fu brakes.

MaineZJ
01-20-2005, 09:40 AM
what condition are all the soft lines?

anthonyh75
01-20-2005, 04:39 PM
The lines look to be in pretty good shape. I have replaced the front with Stainless Steel lines hoping that would prevent and flex. I didnt notice any improvement in stopping after replacing them. All the other lnes look to be in ok shape. No cracks and they are not brittle or anything.