my brakes started to feel spongy a couple of weeks ago and the other day my brake light came on so i checked the fluid levels and it was all brown and murky so i siphoned all the old fluid out and put new in. Also the caps seal looked broken so i went and got a new one from a JY. when i went to bleed my brakes the rear brakes would only squirt out fluid and wouldnt have a good stream unlike the front brakes which bleed perfectly. After bleeding the rears for a while we reset the battery and the brake light is still on and the brakes still feel a bit spongy. what could it be? what could cause the rear brakes not to bleed properly?

thanks,
joma

ps. i already unplugged the sensor at the master cylinder to make sure it wasnt that parking brake sticking and the light went off
pps. when the brakes started feeling spongy i checked the fluid levels and it never changed for the past couple weeks. i also inspected all the brake lines, no leaks. the brake lines actually looked pretty new so the previous owner mustve replaced them

 

for one thing, when bleeding brakes you have to do it in the order of farthest from the reservoir first...rear pass, rear driver pass, front pass, front driver side.
Did you check your rear break drum cylinders? How are your brake pads? pull up on ur break pedal and see if your break lights turn off. You might need new break pads too. If its spongy it can also be your master cylinder (o-rings deteriorating, needs rebuild).
I experienced the same thing when I first got my XJ and all those were the culprit.

 

Master cylinder went out sounds like mine done the same thing a few weeks ago replaced it bled the brakes and it stops really good now, fyi if you replace the master if your jeep is a pre 94 get one for a 95 up there better,

 

I'm a bit concerned about how air got in the rear lines in the first place. Unless you opened the system for repairs, air in the lines means you either ran the MC dry, or the MC is shot, or you have a leak somewhere. A leak in the rear lines or blown MC seal would also make them impossible to bleed. Any sign of fluid anywhere? Along the lines? Wheel cylinders? If no leak, do as the above poster mentioned and grab a new MC.

 

started the jeep this morning and the light didnt come on!!! and the brakes feel a whole lot better. hopefully the light stays off.