Description And Operation Of Tractor Components; Engine And Its Systems; Engine; General Information - Belarus 80.1 Operation Manual

3 Description and operation of tractor components

3.1 Engine and its systems

3.1.1 Engine

3.1.1.1 General information

Note – In subsection 3.1.1 "Engine" brief information about the engine and its com-
ponents is given. To get full information about engine composition and operation, its com-
ponents, it is necessary to obtain from your dealer the operation manual of the engine 243-
0000100OM (or 243C/245C-0000100 OM, if the engine 243C is mounted on your tractor)
compiled by OJSC "MMZ".
On tractors "BELARUS-80.1/82.1/820" the engine Д-243 is installed. Upon request
on tractors "BELARUS-80.1/82.1/820" the engine Д-243С can be installed, which accord-
ing to hazardous substances emissions complies with ecological requirements of Stage I.
The engine Д-243/243С is a four-stroke, piston, four-cylinder internal combustion
engine with in-line vertical arrangement of cylinders with direct diesel fuel injection and com-
pression ignition.
To ensure positive start in the conditions of low ambient temperatures heating plugs
of rated voltage 11V can be installed in the engine head.
Engine is started by imparting rotation to the crankshaft by the electric starter through
the flywheel, mounted on the flange of the crankshaft.
The operation principle of the engine Д-243/243С, like any internal combustion en-
gine, is conversion of thermal energy of the fuel, combusting in the working cylinder, into
mechanical energy. When the piston moves down, at suction stroke, air charge enters the
cylinder through the open intake valve. After the intake valve closes and the piston moves
up high air compression occurs. Herewith air temperature rises abruptly. At the end of com-
pression stroke fuel is injected under high pressure through the nozzle. When injected, the
fuel is finely atomized, mixes with hot air in the cylinder and evaporates, forming a fuel-air
mixture.
Ignition of the mixture during engine operation is a result of high air compression to
the temperature of the autoignition of the mixture. Fuel injection, in order to avoid prema-
ture ignition, begins only at the end of the compression stroke.
After combustion of the air-fuel mixture, the process of expansion and cleaning of
the cylinder from the combustion products through the exhaust valve follows.
The coordinated opening and closing of the intake and exhaust valves is controlled
by a valve timing mechanism.
The engine cooling system water pump is driven by means of belt transmission from
the pulley, mounted on the crankshaft tail, to the pulley, mounted on the water pump roller.
The drive of the pneumatic compressor and gear pump of the steering is carried out by
toothed gear of the valve timing mechanism.
Absorbing of the energy (power) generated by the engine for driving the tractor, the
machine, on which it is installed, is carried out from the flywheel through the clutch.
The engine during operation provides automatic power control to maintain a con-
stant speed (set or nominal) using the speed controller mounted on the high-pressure fuel
pump.
The main components of the engine are: block of cylinders, cylinder heads, pistons,
connecting rods, crankshaft and flywheel.
89
80-0000010B OM