About every third time I apply the brakes in my YJ it will go all the way to the floor. It still stops, but seems to loose all hydraulic pressure. If I press it a few more times it builds pressure up again. Would bleeding my breaks help? There are no leaks anywhere!
1987 YJ Laredo/3" Body/30X9.5" All Terrains/Rebuilt 258/BA 10/5
Bleeding them would be a good start. How many miles on the components? My sons Laredo has 250,000 miles on it, we have been slowly replacing everything, the body, frame and rear end housings are about the only thing not worn out, oh yeah and the transfer case hasn't been used much. Hope this helps out.
Did you check the wheel cylinders in the rear? Double check all of the hose and line fittings, and around the master cylinder for leaks.
Bleeding may help but if air comes out you need to find out how it got in there. Otherwise this will just keep happening. If everything else looks ok your master may be worn out and leaking internally.