Never disassemble the oil pressure relief valve spring and plunger from the oil pump; if the oil pressure relief valve is defective replace the complete oil pump assembly. First un-bolt and take-off the timing belt and the crankshaft sprocket, then the oil pan and the oil pump pick-up tube. Next, remove the bolts and its cover using a wrench, after that pull out the oil pump from the block. For inspection, unbolt the cover from the back of the oil pump housing and remove the inner and outer rotors and as a process make sure of the direction they are to be reinstalled. wash all parts in solvent and inspect the rotors, pump cover and housing for such damage as score, wear, pitting or denting; if any, replace the assembly. Check the oil pump cover for warpage with the help of straight edge and the feeler gauge; if found to be warped beyond the limit then replace the pump. The thickness and diameter of the outer rotor should be measured with a micrometer and, if the thickness is less than or the diameter is more than the specified limit, the pump should be replaced. Check the thickness of the inner rotor and if you find it is less than the prescribed limit replace the pump. Insert the outer rotor into the housing and then measure the clearance at the opposite side: if this clearance is higher than the maximum allowable, replace the pump. The inner rotor shall be put in place and the gap between the indentations of the outer and inner rotors taken; if this gap is larger than indicated the pump assembly shall be replaced and the inner rotor put in place with the mark uppermost. Gauge the side clearance with a straightedge against the faces of the pump housing and the rotors: if the measurement is more than the acceptable limit, change the pump. For installation, first, pour engine oil into the housing of the oil pump and install the pump cover and thereafter tighten the bolts up to the recommended torque value. The gasket must be placed on the mating surface of the engine block while the flats of the rotor must be engaged with the crankshaft before the oil pump housing is placed on the engine block. Last, add and torque the pump to block bolts and do the reverse to how they were removed to finally complete the installation.
