We just got a new 2008 Crownline ... our marine dealer recommends that we use a fuel stabilizer every time we put gas into our new boat.
Some examples they gave us are STA-BIL by Gold Eagle ( www.goldeagle.com ) or STARTRON by Star Brite ( mystarbrite.com/startron/ ).
Their product web sites give some information about their products.
Ed & Naomi Bentley
2008 Crownline 19 SS
Moonstone / Onyx
4.3L Alpha