Oil pump parts
1. Pump (chain cover); 2. Pressure reducing valve; 3. Springs; 4. Plate; 5. Retaining ring 6. Crankshaft oil seal; 7. Pump cover; 8. Leading rotor; 9. Slave rotor; 10. Gasket
Removal
1. Remove the belts and tensioner roller.
2. Remove the tray.
3. Remove the crankshaft pulley. Remove the chain cover to access the pressure relief valve.
The original can be found on this resource [TOYOTAMAN]
4. Remove 9 screws (indicated by arrows) and remove the oil pump housing.
5. Remove any remaining seal from the split surfaces of the pump and cylinder block and wash the surfaces with solvent.
6. Remove the leading and trailing rotors.
7. Carefully disassemble the pressure reducing valve.
Examination
1. Wash all parts in solvent, check for wear and damage.
2. Check the condition of the sliding surface of the pressure reducing valve piston and spring. If damage is detected, replace the piston and spring together.
3. Check the gap between the driven rotor and the housing with a feeler gauge.
4. Check the rotor end clearance between the rotor and the cover with a feeler gauge.
5. Use a feeler gauge to check the clearance between the leading and driven rotors.
6. Compare the measurement results with the standard ones. If the gaps exceed the standard, replace the rotors in the set. If necessary, replace the pump body (chain cover).
Installation
1. Lubricate the rotors with engine oil and install them into the housing.
2. Place technical petroleum jelly in the pump cavities, place the gasket, install the cover and tighten the screws.
3. Lubricate the relief valve piston with fresh engine oil and install the valve parts.
4. Install the new chain cover gasket onto the guide pins.
5. Install the chain cover by engaging the oil pump drive rotor shaft with the crankshaft drive gear.
6. Install the remaining parts in reverse order.
7. Fill with oil, start the engine, check for leaks.