If I were you, I think I'd consider just doing a full brake job if you don't know how long it's been...with all new parts. Less than $100 and a weekend project and the system will be like brand new again. A Haynes or Chilton's manual, as lousy as they are for most things, will walk you thru a brake job perfectly fine if you haven't done one before. Just do one wheel at a time, using the other side as a model for when you forget where a spring goes...