4. LUBRICATION SYSTEM ATV 300/250 Oil Pump Driven Sprocket Oil Pump Drive Chain Remove the two oil pump bolts for remove the oil pump. Oil Pump Bolts Screw OIL PUMP DISASSEMBLY Remove the screw and disassemble the oil pump. Pump Body INSPECTION Measure the rotor end-to-pump body clearance. Service Limit: 0.12 mm (0.0048 in) 4-4