1997-2001 Honda TRX250 Fourtrax Recon Service Manual, Page 66Get this manual
LUBRICATION SYSTEM Remove the washer and il pump shaftMark the rotors which side is up, so they can be reinstalled the same wayDisassemble the oil pumpOIL PUMP SHAFT
Thoroughly clean all the components Install the outer and inner rotors into the pump body and temporarily insert the oil pump shaftMeasure the pump body clearance