2004-2005 Kawasaki STX-15F Jet Ski Factory Service Manual., Page 131Get this manual
FUEL SYSTEM (DFI) 3-83 Fuel ilter
Fuel Filter Insta lla tion
rl Routtengthseechtoosneincorpecetnydi(xsehaCtaebr)le, Wire, and Hose Rou Ap cp Install the fuel hoses to the fuel filter, noting its "IN" fitting [A] and "OUT" fitting [B]