5.3.1. Case details
Block of cylinders
The block of cylinders is cast from gray cast iron and makes a single whole with cylinders with the top part of a case. Between cylinders there are channels for cooling liquid.
On the top plane of the block ten carving openings of M 14х1,5 for fastening of a head of the block of cylinders are located. In the lower part of the block five support of radical bearings of a bent shaft are located. Covers of radical bearings are made of malleable cast iron; each cover fastens to the block two bolts of M12u1,25. End faces of the third cover are processed together with the block for installation of semi-washers of the persistent bearing. Covers of bearings are chiseled assembled with the block and therefore at repair they should be established on the places. For simplification of installation on all covers, except the third, their serial numbers are beaten out ("1", "2", "4", "5")
To a forward end face of the block through paronitovy laying (left and right) the cover of chains of the drive of camshafts cast from aluminum alloy with a rubber epiploon for consolidation of a sock of a bent shaft fastens.
To a back end face of the block fasten:
- six bolts of M6 a cover with a rubber epiploon for consolidation of the back end of a bent shaft;
- six bolts of M10 and two adjusting pins the bell-shaped case of coupling cast from aluminum alloy.
Besides, for ensuring additional rigidity of fastening of a case of coupling its lower part is connected to the block of cylinders by means of the G-shaped amplifier cast from aluminum alloy. The horizontal plane of the amplifier four bolts of M10 fastens to the lower plane of the block of cylinders, and the vertical plane — two bolts to a coupling case.
Exact installation and rigidity of fastening of a case of coupling are necessary for the correct operation of the transmission.
The technology of processing of a case of coupling provides its interchangeability.
Head of the block of cylinders
The head of the block of cylinders is cast from aluminum alloy (the general for all cylinders). Inlet and final channels are executed separately for each of sixteen valves and located: inlet — with right, final — on the left side of a head.
Nests for valves are located in two ranks rather longitudinal axis of the engine. Each cylinder has two inlet and two final valves. Cores of valves have an inclination to the longitudinal vertical plane of a head of cylinders: inlet — 17 °, final — 18 °.
Saddles and plug-in directing plugs of all valves. Saddles are made of heat resisting cast iron, the directing plugs — of gray cast iron.
Thanks to a big tightness when landing a saddle in a nest and the directing plug — in a head opening, their reliable landing is provided. At the plant, before assembly, the head heats up to temperature of 160 — 175 °C, and saddles and the directing plugs are cooled in nitrogen dioxide ("artificial ice") up to the temperature approximately minus 40 — 45 °C. At the same time the saddle and the plug freely or with easy effort are inserted into a nest or an opening of a head. In addition head metal around saddles is pressed out by means of a mandrel.
Facets in saddles and openings in plugs are processed assembled with a head.
The head of the block of cylinders fastens to the block ten bolts of M 14х1,5. Under heads of bolts the flat steel thermostrengthened washers are put. Between a head and the block assembled with a cover of chains the laying from the asbestos cloth reinforced by a metal framework covered with graphite is established. Windows in laying under combustion chambers and an opening of the oil channel are edged by a tin. Laying thickness in the compressed state — 1,5 mm.
In the top part of a head of the block of cylinders two rows of support under necks of camshafts — inlet and final valves, in each row on five support are located. Support are formed by a head of the block of cylinders and removable aluminum covers. The forward cover is the general for forward support of camshafts of inlet and final valves, four, other covers — two bolts of M8 fasten to a head. The correct provision of a forward cover is provided with two adjusting pins plugs pressed in a head of the block of cylinders.
Covers of support are chiseled assembled with a head and therefore at repair they should be established on the places. For simplification of installation on all covers, except a lobby, numbers (fig. 4.113) are beaten out. Numbers are beaten out by a brand in the center of the round lugs cast on the top surface of covers. Lugs are displaced concerning an axis of covers: on covers of support of the camshaft of inlet valves — to the right, on covers of support of the camshaft of final valves — to the left, observing from a coupling case. Numbers "1", "2", "3" and "4" belong to covers of support of the camshaft of inlet valves, and numbers "5", "6", "7" and "8" — to covers of support of the camshaft of final valves. The account begins from a forward cover.
The correct provision of a head on the block is provided with two adjusting pins plugs pressed in the block of cylinders.
Combustion chamber volume at the valves put into place and the screwed candle makes (57±0,75) cm3. The difference between volumes of combustion chambers of one head should not exceed 1 cm3