I have a problem my 94 full size blazer has some brake issues. I been noticing a spongy brake. Pedal going further to the floor and the brake light comes on and stays on. I have replaced the front brakes and found a leaking wheel cylinder on the RR. I have replaced all that and bleed the brakes and still spongy brakes and the light comes on I have to pump the brakes to make them work with good pressure. The light stays on and i have to kick the pedal and it goes out. i have no vaccum leaks or fluid leaks. I have replaced the master cylinder and front brake pads and RR wheel cylinder. Up in arms and sick of pumping brakes to stop any suggestions would help out tremedously.

Thank You
Jason

 

There have been more than a few vehicles which I have had a heck of a time getting all of the air out of the system. Many of them I have cracked the bleeders and let sit for a few days, just topping off the master cylinder, only to still have a spongy brake pedal. Sometimes it takes more patience than a saint to get all of the air out. If you see a surge of fluid in the master cylinder when you press on the brake, then the air is not entirely out of the master cylinder.

 

ok i craked all the bleeders and let the them drip for about 2 hours. Then bleed all the brakes again.And still having the same issues
I drove it and slammed on the brakes and the ABS kicked in a little but the front tires locked up and squealled. Its really bad squealling in reverse when slamming on the brakes from about 30 mph. Any suggestions now would be very helpfull

Thanks
Jason

 

Bad Master cylinder? ive bought rebuilt and got a dud right out of the box before.just a thought...did you bench bleed the master before bolting on? sounds alot like a master cylinder thing.

 

I agree with rlawrencek, I had the same problem with my 1974 corvette stingray. my brakes got to were I had to pump them or slam on the pedal real fast to get them to work. I also got a dud master cylinder the first time I replaced it. bench bleeding is very important, it seemed to take forever, and you have to get all the air out of it. even when its just little bubbles. it took me probably half an hour to get all the air out. make sure you put those plastic screw-in plugs to so it does not leak at all. if you don't when you release the piston it will pull air back into the cylinder.