To complete the job you will need a piston ring mandrel.
Removal
1. Remove the cylinder head (see "Cylinder head - removal and installation").
2. Remove the engine oil pan (see "Engine Oil Pan - Removal, Gasket Replacement and Installation")
3. Remove the oil intake (see "Oil intake - removal and installation").
4. Turning the crankshaft by the bolt securing its pulley with a 17 mm wrench, set the piston of the first cylinder to the lower position.
5. Using a TORX E10 key, unscrew the two nuts securing the connecting rod cover of the first cylinder.
6. Remove the connecting rod cover.
7. Press the hammer handle against the piston and push it upward.
8. Remove the piston from the cylinder.
9. Remove the liners from the connecting rod and its cover.
10. Fix the piston by the connecting rod in a vice. Slightly moving the ring lock apart, we remove the upper compression ring. In a similar manner, we remove the lower compression ring, the oil scraper ring and its expander.
Tip: The rings are thin, so to avoid breaking them, cut a strip from a plastic bottle that is slightly shorter than the circumference of the piston. Place the edge of this strip under the lock of the upper compression ring, and then around under the entire ring.
Remove the strip from the piston together with the ring. Remove the second compression and oil scraper ring in the same manner.
The advisability of replacing rings depends on the degree of wear of the cylinders. Slightly uniform wear of cylinders (within 0.05 mm) can be compensated by installing a piston of a different class with a larger diameter (see "Piston and connecting rod - replacement").
Installation
1. Thoroughly clean the piston from carbon deposits and deposits. We inspect the piston, connecting rod and pin. Cracks on them are unacceptable.
We select new rings in accordance with the piston diameter - nominal or repair size.
2. Before installing new rings, use a set of feeler gauges to measure the gap between the piston ring and the wall of the groove into which the ring will be installed.
Table 8.1.3. Permissible clearances between groove walls and piston rings
Note: Permissible clearances between the groove walls and the piston rings are indicated in the table. 8.1.3. If the clearance exceeds the maximum permissible value, the piston must be replaced.
3. To select piston rings based on the thermal clearance, install the rings one by one into the cylinder block to a depth of 20-30 mm and use a set of flat feeler gauges to determine the clearance in the lock.
Note: Maximum permissible thermal clearance during wear (for used rings) - 1 mm, the gap for new rings is 0.25-0.45 mm. If the gap exceeds the maximum permissible, the ring must be replaced.
4. Put the rings on the piston. In this case, the oil scraper ring...
...and we install the compression ring with the inscription "TOP" facing up.
We install new rings on the piston, starting with the oil scraper ring expander.
Using a mandrel, we put on the oil scraper ring, and then the lower compression ring (we put the rings on the mandrel and carefully move them down until they fit into the groove).
We put on the upper compression ring without a mandrel: by moving the ring lock apart (no more than is required to put the ring on the piston), we first place the lock on the piston, and then the back part of the ring.
5. Turn their locks so that they are located at an angle of 120° relative to each other. The expander lock must be rotated 180° relative to the ring lock.
6. Lubricate the cylinder wall with clean motor oil...
...and the outer surface of the piston.
7. Place the mandrel on the piston and use it to compress the rings, periodically tapping the mandrel lightly with the hammer handle to ensure the rings are self-installing.
Warning! Connecting rod caps are not interchangeable. The engine is equipped with "split connecting rods" whose covers are made using a special method. The contact surfaces of the cover and connecting rod are uneven, which ensures perfect fit of the parts during assembly.
8. Wipe dry the bearing beds in the connecting rod and cover and install the bearings in them.
9. Lubricate the inner surface of the bearings with clean motor oil.
10. Install the piston into the block cylinder.
Warning! The arrow on the piston crown must point towards the crankshaft pulley.
11. Pressing the mandrel against the block and tapping the bottom of the piston with the hammer handle, we press the piston into the cylinder (at the same time we control the movement of the connecting rod towards the crankshaft journal).
12. Install the cover on the connecting rod and tighten the bolts to a torque of 43.32-53.51 Nm (4.42-5.46 kgf·m).
We assemble and install the other three pistons in the same way.
After installing all the pistons, we assemble the engine in the reverse order of its disassembly.