Pistons and cylinders
In the upper third of each piston, three piston rings are placed in corresponding grooves. They are pressed against the cylinder wall under the action of spring forces. Both top piston rings block the way of gases from the combustion chamber down to the engine crankcase, while the bottom oil scraper ring prevents oil from entering the combustion chamber from the engine crankcase.
The cylinder in which the piston moves up and down is made in a gray cast iron engine block. Cylinder bores honed (polished) crosswise. The walls should not be completely smooth, because. otherwise, the oil needed to lubricate the cylinder cannot be retained on them. The cylinder bores are 0.03 mm larger than the corresponding pistons. Cylinders during engine repair can be reground up to three times.
Crankshaft
The task of the crankshaft is to convert the reciprocating motion of the pistons in the cylinders into rotational motion Separate knees (cranks) located at certain angles to each other. For the engines under consideration, they are located at an angle of 180°, i.e. stand opposite each other. For vibration-free operation, counterweights are located at opposite ends of the crankshaft journals.
In order to avoid bending the crankshaft during operation, it relies on 5 main bearings in the engine block. Each crank with connecting rod left and right «propped up» main bearings.
Behind in relation to the direction of movement on the crankshaft is a disk with a ring gear for the starter gear. This is either the flywheel, on which the clutch is strengthened and, thus, the connection with the gearbox (checkpoint) or the drive disc on the automatic transmission torque converter. At the other end of the crankshaft, a gear wheel is screwed to drive the toothed belt and a pulley for the V-belt (belts).
Elements of the cylinder block 1.6 and 1.8 liter engines
A - models with a manual transmission;
B - models with automatic transmission;
1 - cylinder block;
2 - oil separator;
3 - stuffing box;
4 - gasket;
5 - back cover;
6 - plate;
7 - casing;
8 - flywheel;
9, 11 - liners (main bearings) crankshaft;
10 - crankshaft;
12 - main bearing caps;
13 - sleeve;
14, 16 - adapter plate;
15 - drive plate.
Attention: The installation elements of the cylinder block of the 2.0 liter engine are made in the same way.
Four connecting rods with replaceable bearing shells are mounted on the connecting rod journals of the crankshaft. At the other end are bronze bushings for the piston pins, which are made «floating». Pistons and piston pins can therefore move slightly back and forth on the connecting rod.
Elements of the crank mechanism
1 - upper piston ring;
2 - lower piston ring;
3 - oil scraper ring;
4 - piston;
5 - piston pin;
6 - connecting rod;
7, 8 - connecting rod bearing shell;
9 - connecting rod cover.