Buick 8665230 PUMP,W/CO

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 beforehand. Begin by removing the pump cover retaining screws and the pump cover, marking the gear teeth for reassembly. Next, take out the idler gear, drive gear, and shaft from the body. Remove the pressure regulator valve retaining pin using needle-nose pliers, followed by the regulator valve and its related parts. For V6 engines, the pick-up screen and pipe assembly can be extracted from the pump body, while on L4 engines, the screen assembly is factory-fitted and cannot be separated. Clean all parts in solvent and dry them thoroughly, inspecting the body for cracks, wear, or other damage, and replace the gears if they show excessive wear. Check the drive gear shaft for looseness in the pump body and inspect the inside of the pump cover for wear that could allow oil leakage past the gears; if either the gears or body are worn or damaged, the entire assembly must be replaced. Inspect the pick-up screen and pipe assembly for damage, and if the V6 screen assembly was removed, replace it with a new one. Apply gasket sealant to the end of the pipe and carefully tap it into the pump body to avoid damage. 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 toward 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 that the pump operates freely.

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 beforehand. Begin by removing the pump cover retaining screws and the pump cover, marking the gear teeth for reassembly. Next, take out the idler gear, drive gear, and shaft from the body. Remove the pressure regulator valve retaining pin using needle-nose pliers, followed by the regulator valve and its related parts. For V6 engines, the pick-up screen and pipe assembly can be extracted from the pump body, while on L4 engines, the screen assembly is factory-fitted and cannot be separated. Clean all parts in solvent and dry them thoroughly, inspecting the body for cracks, wear, or other damage, and replace the gears if they show excessive wear. Check the drive gear shaft for looseness in the pump body and inspect the inside of the pump cover for wear that could allow oil leakage past the gears; if either the gears or body are worn or damaged, the entire assembly must be replaced. Inspect the pick-up screen and pipe assembly for damage, and if the V6 screen assembly was removed, replace it with a new one. Apply gasket sealant to the end of the pipe and carefully tap it into the pump body to avoid damage. 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 toward 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 that the pump operates freely.

Remove the oil pan. For L4 engines, take out the two oil pump flange mounting bolts and the nut from the main bearing cap bolt. For V6 engines, remove the bolt that secures the pump to the rear main bearing cap. Lift off the oil pump and screen as an assembly. To install, align the pump shaft to mate with the oil pump drive shaft tang. Position the oil pump housing flange and install the mounting bolt(s), ensuring no gasket is needed between the pump flange and the block. For L4 engines, install the oil pump screen bracket over the main bearing cap bolt and secure it with the nut. Torque the pump mounting bolt(s) and main bearing nut to specifications. Finally, install the oil pan.

Torque the pump mounting bolt(s) and main bearing nut to specifications.

Install the oil pump and driveshaft extension, engaging the driveshaft extension in the distributor drive gear, followed by the pump-to-rear bearing cap bolt, tightening it to the specified torque.

Consult the relevant part for inspection and overhaul procedures for the oil pump.

Install the oil pump screen bracket over the main bearing cap bolt and secure it with the nut.

Reinstall the oil pan.

Check the drive gear shaft for looseness in the pump body and inspect the inside of the pump cover for wear that could allow oil leakage past the gears. If either the gears or body are worn or damaged, the entire assembly must be replaced.