As with many of these tutorials, it may be necessary to remove the oil pump from the engine before you begin. It is unfastened by taking off two bolts which fixes the pick-up tube in place, then, the pick-up is removed. Solvent clean the oil pump and then blow dry the oil pump with air compressor. Subsequently, the oil pump housing cover should be taken off and the part is secured by four bolts. Although the oil pump has been removed from the housing, its interior is still needed to be cleaned, and the best way to do this is to immerse a brush and solvent into those areas shown in figure 6 and scrub out any dirt which may be stuck inside the pump housing and pressure relief valve chamber. On the inside of the pump housing, outer race and the rotor, check for signs of wear, scoring or other damages; on the pump cover, check for wear, grooves or other damages; where these are evident, replace the pump with a new one. Take a feeler gauge and measure the outer race-to-housing clearance and compare the findings with the specifications. Insert a straightedge and feeler gauge and check end plate-to-rotor assembly clearance and then look for conformity to specification. The driveshaft-to-housing bearing clearance shall be checked by measuring the inner diameter of the housing bearing and then subtracting it from the outer diameter of the driveshaft, and then comparing the two results with the specifications. It is not possible to service any of the components, so if some of them fail the check, then the whole oil pump must be changed. Check the relief valve spring for being worn or collapsed, and the relief valve piston for scoring, damage and free and smooth functioning in its bore; in case the relief valve fails any of the above test, then replace it completely with a new one. Place the rotor, outer outer housing and race in the oil pump, fill the cavities of the pump with petroleum jelly to enable the oil pump suction when the engine is running. Lastly the cover and the four nuts of the retaining bolts are to be tightened to the specified torque and the pick-up tube is to be fastened to the oil pump body by using a new gasket and tightening the nuts of the pick-up tube to the specified torque.