Nissan Automatic Transmission Oil Pump Exploded Diagram & Inspection (AT-22)

This is page AT-22 from a service manual's automatic transmission section, titled 'Repair for Component Parts – Oil Pump.' The top half shows an exploded diagram (figure SAT288) of the automatic transmission oil pump assembly, with labeled components: needle bearing, seal rings, thrust washer, oil pump housing, oil pump outer gear, oil pump inner gear, oil pump gear hub, oil pump plate, oil pump shaft, pressure relief spring, and steel ball, plus a note to 'align these holes.' The lower half provides an inspection procedure in five steps: inspect the oil pump body, shaft and ring groove areas for wear; remove the oil pump plate; inspect gears and internal surfaces for faults and wear; measure clearance between the outer gear and crescent (standard clearance 0.20–0.30 mm / 0.0079–0.0118 in); and measure clearance between the outer gear and pump housing (same standard clearance). The page specifies replacing the oil pump inner and outer gear and the oil pump housing if clearance exceeds 0.35 mm (0.0138 in). Two supporting illustrations (SAT289 and SAT291) show the inspection and feeler-gauge clearance measurement procedures.