Dimensions of the main mating parts of the engine and limits of permissible wear during operation
Mating parts | Dimensions of mating parts, mm | Permissible clearance in the mating, mm | |
| Hole | Shaft | ||
| Piston - cylinder: | |||
| Class A | 76,00–76,01* / 79,0–79,01 | 75,94–75,95 / 78,93–78.94 | 0,15 |
| Class B | 76,01–76,02 / 79,01–79,02 | 75,95–75,96 / 78,94–78,95 | 0,15 |
| Class C | 76,02–76,03 / 79,02–79,03 | 75,96–75,97 / 78,95–78,96 | 0,15 |
| Class D | 76,03–76,04 / 79,03–79,04 | 75,97–75,98 / 78,96–78,97 | 0,15 |
| Class E | 76,04–76,05 / 79,04–79,05 | 75,98–75,99 / 78,97–78,98 | 0,15 |
Piston – piston pin**: | |||
| 21,982–21,986 | 21,970–21,974 | – |
| 21,986–21,990 | 21,974–21,978 | – |
| 21,990–21,960 | 21,970–21,982 | – |
| Upper connecting rod head - piston pin*** | 21,940–21,960 | 21,970–21,982 | – |
| Piston - Upper Compression Ring | 1,535–1,555 (groove width) | 1,478–1,490 (ring height) | 0,15 |
| Piston - Lower Compression Ring | 2,015–2.035 (groove width) | 1,978–1,990 (ring height) | 0,15 |
| Piston - oil scraper ring | 3,957–3,977 (groove width) | 3,925–3,937 (ring height) | 0,15 |
Cylinder - piston ring (gap in the ring lock): | |||
| 0,30–0,45 | 0,30–0,45 | The compression in the cylinder must be at least 10 kgf/cm² |
| 0,25–0,40 | 0,25–0,40 | |
| Cylinder block plus main bearings – crankshaft | 54,507–54,520+2(1,824–1,831) | 50,775–50,795 | 0,15 |
| Crankshaft (length of the back neck) - cylinder block (rear support width) plus thrust half rings | 27,975–28,025 | 23,14–23,20+2(2,31–2,36) | 0,35 |
| Connecting rod plus connecting rod bearings – crankshaft | 51,330–51,346+2(1,723–1,730) | 47,814–47,834 | 0,1 |
Camshaft Bearing Housing - Camshaft: | |||
| 46,000–46,025 | 45,915–45,931 | 0,2 |
| 45,700–45,725 | 45,615–45,631 | 0,2 |
| 45,400–45,425 | 45,315–45,331 | 0,2 |
| 45,100–45,125 | 45,015–45,031 | 0,2 |
| 43,500–43,525 | 43,415–43,431 | 0,2 |
| Guide Bushing - Inlet Valve | 8,022–8,040 | 7,985–8,000 | 0,15 |
| Guide Bushing - Exhaust Valve | 8,029–8,047 | 7,985–8,000 | 0,15 |
| Auxiliary Drive Shaft - Front Bushing | 48,084–48,104 | 48,013–48,038 | 0,15 |
| Auxiliary Drive Shaft - Rear Bushing | 22,00–22,02 | 21,94–21,96 | 0,15 |
| Oil pump drive gear - bushing | 16,016–16,037 | 15,970–15,985 | 0,15 |
Oil pump housing - gears: | |||
| 30,055–30,117 | 29,956–29,989 | 0,2 |
| 34,08–34,12 | 33,940–33,970 | 0,25 |
* In the numerator – for the 2103 engine, in the denominator – for the 2106. Since 1988, the piston diameter on the 2106 engines has been increased by 0.01 mm compared to that indicated in the table.
** A lubricated piston pin with acceptable wear should not fall out onto the bosses if it is held vertically in the piston.
*** With acceptable wear, the pin is not allowed to slip under a load of 400 kgf.