I have a shallow well about 60-80 feet Icut the 2" casing with a saw zaw and the pipe inside it droped.Icould not get the pipe out so I used 3/4" pex to go inside the inner pipe. Then I put a furnco over the 2" pipe reducing down to 1"pvc up about 3'then a 90 then a tee for priming after the tee a check valve then to a Simer shallow well pump with pre charged tank. Ican prime it to where the pump shuts off but whenI turn on hose it comes out for one minute pump turns on but pulls no water. What am I doing wrong please help.

Did you put a foot valve on the pipe? Sounds like water is running back down into the well and you lost prime.

Why did you cut the casing? What problem were you trying to solve?