I just purchased a used 18' JW pool with a Hayward ST160 sand filter. This is our first pool and I have no idea what I'm doing (although that never stopped me before) I have no idea how old this system is but the pool seemed in good shape. Iím putting a new liner in since the old liner had some hard areas with major wrinkles. What I am looking for is where to find a user manual. I checked Google and found a parts diagram but couldnít find any manual. Even Haywardís site doesnít list it. Iím guessing this thingís pretty old. Does anyone know where I could find one? The guy I got the system from said to remove the bolts to change the sand but I donít even know how much to get. Any help is appreciated.