hi guys, i'm having a problem. i checked the brake fluid in my 70 chevelle and i noticed it was a little low so i added some DOT3. i had good firm brakes before but now my peddle is going almost to the floor. i don't see any leaks and the whole brake system was restored about 8 years ago. the fluid was not low enough to suck air and pumping the peddle doesn't help. i don't know if the fluid that was in there was silicone or DOT. does it sound like the fluid got contaminated or is it a coincident that the master went bad? thanks in advance.

Silicone (DOT5) is usually dyed to avoid mix-ups. All DOT5's I have seen were purple. Is your fluid is clear?