i baught a 280zx from a guy bout 4 months ago and i noticed there was a bottle of brake fluid next to the master cylinder. i decided to change the front and back brakes and everything was fine for 2 months. i dont drive it far, i only put 5 miles on it a day. after two months i noticed the petal go 80% to the floor. i put more fluid in and bled it and went along well for another month. it started drinking the container of fluid from the resivoior and i only drove 2 miles to work. i kept topping it off. i checked for leaks at the calipers, none. the only resevior that is draining is the first one farthest away from the booster cylinder?

 

Welcome to ZDriver!

Have you checked the firewall at your brake pedal for fluid? If all 4 calipers are dry (You took off each tire & thoroughly inspected each one right?), and there is no fluid leaking from the outside of the master, then it's probably leaking from the plunger side.

 

I had the same problem. It would be fine, then the fluid would dissapear from the res, no trace of where it went. I replaced the master cylinder and all is good. The hardest part of the install was bleading the new master cylinder

 

I started to take off the brake master cylinder and i noticed there was some sort of glue around it connecting to the plate to the booster, after i took it off, i realized it was leaking at the booster. i replaced it and now just need to bleed the whole system thanks for all the replys