" should a guy change it out, if so what with, store the old one in the tool box for backup,,,," I did..... but then I am having problems too. Not related to that though. There are a number of threads here that tell you what your output should be and some very knowledgable folk too. If it passes the test then it just depends on how much preventative stuff you want to do and can afford. Some of the experts can help out and tell you what fuel flow you should have. Good luck on your project.