2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 135Get this manual
CARBURATION AND FUEL SYSTEM 13Install new PFA gasket onto the sending unit assembly using care not to damage gasket or bend float arm14Install the sending unit into fuel tank, hold float arm to the sending unit body and tilt assembly to ensure float arm does not get caught or bent during installation15Gently push down on sending unit flange ensuring flange is centered16Roughly align capped vent fitting with orientation marks on fuel tank to ensure float arm does not get bent or snagged
CAUTION
Failure to align the orientation marks may lead to interferences with the fuel level float arm and cause incorrect function17While maintaining downward pressure, thread new PFA nut onto fuel tank and hand tightenUse care when starting PFA nut, ensuring threads are properly alignedVerify orientation marks are still aligned between sending unit and fuel tank18Torque PFA nut to specification using the Fuel Pump Service Tool (PU-50326), inextension (if needed) and calibrated torque wrench