The oil pump and pickup are attached to the
Oil Pan and the drive is through the intermediate shaft which rotates half the crankshaft speed. The removal process involves disconnecting the oil pan to the crankcase, loosening or removing the bolts that hold the oil pump to the crankcase bottom and lifting both the oil pump and pickup out of the crankcase, retrieving the baffle plate where necessary. To inspect, take the screws of the mating flange to lift the pickup tube to retrieve the O-ring seal, then loosen and withdraw the screws to take out the oil pump cover. Clean the pump and check the gear teeth and see whether it is damaged or not. Measure pump backlash, with a feeler gauge placed between the teeth of the gears that are meshed, and rotate the gears just a bit to get the maximum clearance and compare with the stated limit. Measure axial clearance of pump; lay a straightedge in the oil pump casing and place a feeler gauge to determine the clearance between the straightedge and pump gears which is again compared with the limit. When either of the measurements is out of the recommended limit, then the pump will be worn out and it needs replacement. To install It has to install the oil pump cover then screws to the recommended torque then re-fit the oil pickup to the oil pump with a new O-ring seal and screws. Install the crankcase baffle plate (where needed) followed by installation of the oil pump to the crankcase, clamping it with mounting bolts, tightened to the required torque and lastly, the oil pan.