so bought used from an older gent. he said he put some plummer tape on to stop leak. i bought with very slow leak. decided to take off and look at. so it came with 2 extra of the reg. orings with metal on the out side. tryed over and over. l then started adding pipe tape to stop leak. cant get it to seal???? am i missing something??? is there a trick. im beyond frustrated. any help would be ....GREATLEY APPRECIATED