Drove my sons 83 Bird today and felt there was quite a bit of travel in the pedal. They stopped fine but dont think they would re-act well in a panic stop. Anyhow brought it in the garage and popped the cover off the master and the fluid level in the frt chamber was way down. Last summer after he got the car we had to replace the frt hoses and bled the brakes and all was fine. This car sat all winter and there were zero leaks under it when we took it out of the garage. I see no leaking at the master/booster. Any suggestions would be greatly appreciated. After re-filling the master it stops just like it did last year and the pedal is much firmer. Thanks
with nothing leaking i would say when you bled the brakes you let too much go without refilling it before storage. the only place i've known my car to lose brake fluid was the wheel cylendars in the drum brakes. if they havnt been replaced yet, you might want to start there if fluid levels mysteriously get lower and lower without noticable puddles etc. to tell you the truth, i didnt even know my rear brakes were leaking untill i felt something was wrong with the drums and went to replace the shoes.
im sure the other guys would have better insight on this problem tho. does the fluid infact drop when you refill it? or did the top off "fix" it? sounds almost like you fixed it but are rightfully worried about it.
83-86 use two resiviors, not one like the 87-88's. I would bet you have a small leak somewhere. I wonder if you could dye your brake fluid with green to see if you can find an obvious leak? I'll bet food coloring would work fine. Also, a new master cylinder is all of 2 seconds of work and less then $20 at autozone, cheap insurance.
I'm not sure if dying brake fluid would bother its stopping abilities, but it would make it very visable if there were a leak. I would try stepping on the brakes alot, if you want, while its on the jack stands or in the driveway.
First place I'd check would be the wheel cylinders (actually, the first place I'd check would be the lines, but I assume you've already checked those). If they're dry remove the nuts holding the master cylinder to the booster and move it ahead to see if any fluid is leaking out the rear of the m/c and into the booster.
Both wheel cylinders are dry, checked for the master leaking into the booster and no leak there either. Obviously it went somewhere though. I guess I will drive it tomorrow and see whats up.
well duhh,,
thats why you look under the master cyl moutning to the booster and look for ANY signs of wetness. you may find your fluid in the booster, or inside the car.