For something that should be so simple, I seem to have to work at getting the plastic cap to start the threads after inserting a new filter. Of cousre, it is not in an easy place to get to but that is likely a secondary consideration. Anybody have any ideas. The new filter seems to fit very tightly in the cap and that might be working against me as I try to begin turning the cap and filter in the housing and trying to get the threads to 'catch'.