My smell from my TT went away when I replaced the toilet. I am fairly sure it was drawing air through the toilet seal, the floor seal not the valve. Always try replacing the installed foam seal with a proper wax one as a first resort.
2004 Chev Silverado Duramax optioned past the max. 2009 Jayco Eagle 308 RLS 765 watts of solar, 6-6 volt batteries (696 amp hour), 2000 watt (4000 surge) whole house inverter.
140 days boondocking in 2016
211/2015, 196/14, 247/13, 193/12