mine was not tightened right from the get go. really tightened it and worked ok. that was probably your problem . try tightening and have someone turn on the flush outside while you watch inside to see if the snugging worked.
It was a rainy few days at Algonquin Prov park...tarps kept us dry.
Wayne --Belle River (Windsor), Ontario
2013 Sunset Trail Reserve 25RB..
2015 White Chev Silverado 2500HD 4x4 (6.0 l gasser)
2003 Mountain Star 890SBRX Truck Camper