REMOVAL & INSTALLATION WARNING
The oil pump is on the lower front of the engine block. It consists of two gears with meshing teeth, one with internal teeth and the other with external teeth. Oil pressure is controlled by a pressure relief valve and spring assembly. The inner gear is driven by the crankshaft at twice the speed of distributor driven oil pumps. To service the oil pump assembly, removal is necessary. Proceed as follows:
- Remove the fan shroud.
- Raise the car and support it on stands.
- Loosen the crankshaft pulley screws but don't remove them.
- Loosen and remove the power steering pump belt, air conditioner and alternator belt.
- Remove the crankshaft pulley. Attach a crankshaft sprocket wrench using all of the pulley screws and remove the crankshaft screw.
- Remove the camshaft drive sprocket from the crankshaft.
- Remove the oil pump screws and the front oil pan screws and remove the oil pump by prying in the slots with a large screwdriver.
- Replace the gasket and the crankshaft seal. Trim the edges of the gasket.
- Rotate the crankshaft so the oil pump lugs are either vertical or horizontal.
- Cut off the oil pan gasket flush with the front of the block.
- Align the gears of the oil pump with the crankshaft lugs and carefully tap the pump on as far as possible.
- Apply silicone sealant to the edges of the pump and the oil pan and to the pump sealing surfaces. Tighten the screws to 87 in.lbs.
- Install the crankshaft seal with a seal installing tool.
- Install the camshaft drive sprocket and the crankshaft accessory drive pulley, making sure the pins align with the holes. Install the crankshaft screw.
- Install the camshaft drive belt, belt guard, accessory drive belts and the fan shroud. Start the engine and check for leaks or low oil pressure, and adjust the timing.
- Disconnect the battery ground.
- Raise and support the car on jackstands.
- Drain the oil.
- Disconnect the exhaust pipe at the manifold.
- Remove the starter.
- Remove the bellhousing access plate.
- Unbolt and remove the oil pan.
- Clean the gasket surfaces thoroughly.
- Install a replacement seal at the bottom of the timing case cover and at the rear bearing cap.
- Using new gaskets coated with sealer, install the pan and torque the bolts to 10 ft. lbs.
- Install all other parts in reverse order of removal.
See Figure 3
- Remove the engine oil pan. Refer to the 4-151 oil pan removal procedure in this section.
- Remove the two bolts and one nut, and carefully lower the pump.
- Install in reverse order. To ensure immediate oil pressure on start-up, the oil pump gear cavity can be packed with petroleum jelly.
6-232 and 258 Engines
See Figure 4
The oil pump is driven by the distributor driveshaft. Oil pump replacement does not, however affect distributor timing because the drive gear remains in mesh with the camshaft gear.
- Drain the oil and remove the oil pan.
- Remove the oil pump attaching screws. Remove the pump and gasket from the engine block.
- Installation is the reverse removal. Prime the pump before installation; use a new cover gasket.
8-304, 360 and 401 Engines
See Figure 5
The oil pump is located in, and is part of, the timing cover. The pump is driven by the distributor driveshaft. Oil pump replacement does not, however, affect distributor timing.
- Remove the retaining bolts and separate the oil pump cover, complete with filter and gasket, from the timing cover.
- The drive gear and shaft and the idler gear will slide out of the timing cover after removal of the pump cover.
- Prime the pump before installation, and use a new gasket.