1. Drain the oil from the engine crankcase.
2. Remove the oil pan (see subsection 3.1).
3. Unscrew bolt 8 (see figure Lubrication system parts for 1.0L, 37 kW and 1.4L, 50 kW engines) fastening the receiver 20 of the oil pump to the cylinder block.
4. Unscrew the four bolts 19 securing the receiver 20 to the timing gear cover.
5. Carefully remove the receiver 20 and gears 22 of the pump.
6. Clean the oil receiver mesh from dirt and wash it with white spirit. If the screen cannot be cleaned or is damaged, replace the oil pan.
7. Remove cotter pin 5, being careful not to let spring 7 pop out.
8. Remove spring 7 and ball 6 of the pressure reducing valve.
9. Inspect the relief valve seat. There should be no burrs or deep scratches on its inner surface. Ball 6 should move completely freely in the socket. Otherwise, replace the oil pan.
10. Install the gears into the timing gear cover. Place a metal ruler 1 and measure the gap between the ruler and gears 3 (4 – timing gear cover) using a feeler gauge 2. The nominal axial clearance is 0.02–0.1 mm, the maximum permissible is 0.13 mm.
11. If the clearance exceeds the maximum allowable limit, replace the timing gear cover. If the clearance is less than 0.02 mm, install shim 21 (see figure Lubrication system parts for 1.0L, 37 kW and 1.4L, 50 kW engines).
12. Assemble the oil pump in reverse order, having first lubricated the gears, gear shafts, pressure relief valve ball and the mating surface of the oil receiver with engine oil. The tightening torque of the oil receiver mounting bolts is 8 Nm.