I'm sure someone here will know the solution to my problem. Sorry if this isn't the correct place for the question.
I was given an old Daisy 881 a few years ago. It would only hold pressure to 3 pumps. Beyond that the valve would leak out any additional pumps. I purchased a new valve assembly and seal kit to rebuild it. The new valve assembly isn't leaking, but the new chamber seal is not sealng either. I can get one pump in, but any further pumps empties the chamber and starts from scratch. I lubed the new seal when I installed it. I don't see any nicks or deformity with the new chamber seal. Is there some trick to getting them to seal? Or should I just assume I can't see the defect and order another seal?