"Gazelle" Gas-2705>> The engine>> Engines ZMZ-4061, ЗМЗ-4063>> Case details
The block of cylinders
The block of cylinders is cast from grey pig-iron and makes a single whole with cylinders with the top part картера. Between cylinders there are channels for a cooling liquid.
On the top plane of the block ten carving apertures of M 14х1,5 for fastening of a head of the block of cylinders are located. In the bottom part of the block five support of radical bearings of a cranked shaft are located. Covers of radical bearings are made of malleable cast iron; each cover fastens to the block two bolts М12u1,25. End faces of the third cover are processed together with the block for installation of semiwashers of the persistent bearing. Covers of bearings are chiseled in gathering with the block and consequently at repair they should be established on the places. For simplification of installation on all covers, except the third, their serial numbers («1», «2», «4», «5») are beaten out
To a forward end face of the block through паронитовые linings (left and right) the cover of chains of a drive of camshafts cast from an aluminium alloy with a rubber epiploon for consolidation of a sock of a cranked shaft fastens.
To a back end face of the block fasten:
- Six bolts М6 a cover with a rubber epiploon for consolidation of the back end of a cranked shaft;
- Six bolts М10 and two adjusting pins колоколообразный картер the couplings, cast from an aluminium alloy.
Besides, for maintenance of additional rigidity of fastening картера couplings its bottom part is connected to the block of cylinders by means of the G-shaped amplifier cast from an aluminium alloy. The horizontal plane of the amplifier four bolts М10 fastens to the bottom plane of the block of cylinders, and a vertical plane — two bolts to картеру couplings.
Exact installation and rigidity of fastening картера couplings are necessary for correct work of a transmission.
The technology of processing картера couplings provides its interchangeability.
Head of the block of cylinders
The head of the block of cylinders is cast from an aluminium 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 concerning a longitudinal axis of the engine. Each cylinder has two inlet and two final клапaнa. Cores of valves have an inclination to a longitudinal vertical plane of a head of cylinders: inlet — 17 °, final — 18 °.
Saddles and directing plugs of all valves the plug-in. Saddles are made of the heat resisting pig-iron, directing plugs — from grey pig-iron.
Thanks to the big tightness at saddle landing in a nest and the directing plug — in a head aperture, their reliable landing is provided. At factory, before assemblage, the head heats up to temperature 160—175 ° With, and saddles and directing plugs are cooled in nitrogen dioxide («dry ice») to temperature about a minus 40—45 ° by S.Pri it a saddle and the plug freely or with easy effort are inserted into a nest or a head aperture. In addition head metal round saddles is pressed out with the help оправки.
Facets in saddles and apertures in plugs are processed in gathering 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 in gathering with a cover of chains the lining from the asbestine cloth reinforced by a metal skeleton, covered with graphite is established. Windows in a lining under chambers of combustion and an aperture of the oil channel are edged by a tin. A thickness of a lining in the compressed condition — 1,5 mm.
In the top part of a head of the block of cylinders two numbers of support under necks of camshafts — inlet and final valves, in everyone to a number on five support are located. Support are formed by a head of the block of cylinders and demountable aluminium covers. The forward cover is the general for forward support of camshafts of inlet and final valves, fastens to a head four, other covers — two bolts М8. Correct position of a forward cover is provided with two adjusting pins-plugs, запрессованными in a head of the block of cylinders.

Fig. 4.113. The scheme of installation and a marking-off of covers of camshafts




Covers of support are chiseled in gathering with a head and consequently 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 centre of the round lugs cast on the top surface of covers. Lugs are displaced concerning an axis of covers: on covers of support of a camshaft of inlet valves — to the right, on covers of support of a camshaft of final valves — to the left, observing from outside картера couplings. Numbers «1», «2», «3» and «4» concern covers of support of a camshaft of inlet valves, and numbers «5», «6», «7» and «8» — to covers of support of a camshaft of final valves. The account begins from a forward cover.
Correct position of a head on the block is provided with two adjusting pins-plugs, запрессованными in the block of cylinders.
The volume of the chamber of combustion at the valves put into place and the screwed candle makes (57±0,75) sm 3. The difference between volumes of chambers of combustion of one head should not exceed 1 sm 3