It sounds like you are on the right track. Heating the female fitting will expand and make it easier to remove the pipe. You may need bigger pipe wrenches also. Terry

: While rehabing a pitcher pump, fitted to a
: shallow well , I've run into a real problem
: trying to remove the old 1 1/4" galvanized down pipe from the cast iron pump base.
: I've been using liquid wrench and a
: propane torch for three days. to no avail.
: The pipe is in good shape but really
: frozen to the cast iron.