title_body: was working great, now all foam
upvoted_answer: I was in a similar situation as you. I fixed it by venting the keg completely, then sealing everything up and attaching the gas line. I left the pressure off at first though. I slowly rolled it up to about two pounds and poured. I continued to increase the pressure very slowly and now keep it around 8 pounds. It sounds like you are over pressurized when serving.