SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

I reside in Chandler, Arizona. I have a Rainbird sprinkler system. The sprinklers are on three (3) zones on my timer and the drip irrigation is a totally different section on my timer (if that makes any sense). Problem are a few, I have two (2) or three (3) sprinkler heads that are slowly "leaking" from the top. I have replaced a head on a different one that was doing the same and found that I needed to replace the diaphrams (2) which fixed the problem with that one and also replaced the solenoids. Problem was fixed so when I found these heads doing the same I replaced the other diaphrams (2 more) thinking that I fixed that problem (the solenoids for these have also been replaced). However, it did not and I have a few drip irrigation lines that also run continuously. I would love to have the entire system tuned up and upgraded however not able to. It seems like most of my time is struggling with the sprinklers rather than enjoying my yard. If someone could help out it would be greatly appreciated. My next plan of attack will be to replace the sprinkler heads themselves but hesitant because I just have a feeling that that won't take care of it either.