2002 Bombardier Quest 650XT Service Manual, Page 97Get this manual
Section 03 ENGINE Subsection 07 (LUBRICATION SYSTEM)
NOTE: When the axial clearance of the oil pump shaft assembly increases, the oil pressure decreasesCheck the inside of oil pump housing and its cover for scoring or other damagesIf so, change the complete oil pump assemblyCheck the oil filter bypass valve for free movementClean the area from contaminationsInstallation
For installation, reverse the removal procedureTightening oil pump housing screws as per following sequence1 4