2001-2002 Yamaha XLT800 WaveRunner Service Manual, Page 120Get this manual
FUEL FUEL TANK
SERVICE POINTS
Check valve inspection 1Check: Check valve Faulty ReplaceChecking steps: Connect hose to the end of check valve "A" and blow into itAir should come out from end "B"G Connect the hose to the end of check valve "B" and blow into itAir should not come out from end "A"G