Hello, been awhile. Hope I can pick your brains for a minute. About a year and a half ago I had some new frost free sillcocks installed. They have a plastic cap with some sort of pressure valve on top of some kind. Anyway this spring I noticed some water dripping out of them through this plastic cap. Of course I paid no attention until I needed water outside today and the one I usually dont use is spraying water like crazy through this top valve. I took off the black plastic cap, as it just snaps on and off. I was expecting something there to tighten or something like a bib nut, but there is nothing but the smooth white plastic of the valve which is spraying water. Is there a quick fix for these types of leaky valves or am I stuck calling the fellow who istalled them? Thanks!