To gain access and to do away with the oil pump, the engine should be placed at TDC on the compression stroke of the number one cylinder. Subsequently, the oil pan has to be uninstalled together with the balance shaft assembly. Next, it is necessary to take out oil pump housing mounting bolts, at which they should turn out each bolt gradually and with the same amplitude before removing together with the oil pump. For the geometry check the oil pump rotor to housing, tooth tip plus Feel, groove and rotor to body plus feeler plus straight edge measurements are within limits if not replace the pump. Cleaning continued with the pressure relief valve plug removed, the spring and plunger then examined for distortion and scoring with parts replaced, where required. During installation, fill the spaces between the rotors with petroleum jelly to pump prime, put clean engine oil on the pump housing bolts when instaling the housing and then follow the torque tension. After fitting the oil pressure relief valve and the spring assembly on the plug, apply a new sealing washer and screw to the specified torque. Then, proceed to tighten the oil pump housing bolts by hand until just tight and then go on tightening them gradually and uniformly to the given torque setting. Make sure that engine does not move from TDC compression for cylinder number 1, then fasten balance shaft assembly. Top up the engine with oil and replace the oil filter before reconnecting the battery. Last, turn on the engine and often ascertain that the oil pressure indicator returns to normal; if it does not, shut down the engine and figure out the reason so that the engine is not damaged from low oil pressure.