Q: Is it more practical and economical to replace a faulty oil pump with a new or rebuilt unit, and what steps should be taken if an overhaul is chosen in V8 engine on 1985 Chevrolet El Camino?
A: In most cases, it is more practical and economical to replace a faulty oil pump with a new or rebuilt unit, but if an overhaul is chosen, check on the availability of internal parts before starting. Begin by removing the pump cover retaining screws and the cover itself, marking the gear teeth for reassembly. Next, take out the idler gear, drive gear, and shaft from the body, followed by the pressure regulator valve retaining pin, the regulator valve, and related components. If needed, extract the pick-up screen and pipe assembly from the pump body. Clean all parts in solvent and dry them thoroughly, inspecting the body for cracks, wear, or other damage, as well as the gears. Check the drive gear shaft for looseness in the pump body and examine the inside of the pump cover for wear that could lead to oil leakage. Inspect the pick-up screen and pipe assembly for any damage. Apply gasket sealant to the end of the pipe and carefully tap it into the pump body, ensuring no damage occurs; if the original press-fit cannot be achieved, a rear assembly must be used to prevent air leaks and loss of pressure. Install the pressure regulator valve and related parts, followed by the drive gear and shaft in the pump body, then the idler gear with the smooth side facing the pump cover opening, lubricating the parts with engine oil. Finally, install the cover and torque tighten the screws, then turn the driveshaft to ensure the pump operates freely.