Belarus 80.1 Operation Manual page 93

Engine cooling is liquid with forced circulation of cooling liquid from the centrifugal
pump. The temperature of the cooling liquid in the system is controlled by the temperature
indicator in the combination on the dashboard. The temperature indicator sensor is mount-
ed in the cylinder head. A place is provided for mounting of the sensor in the thermostat
body. The engine operation is forbidden when lamp of cooling liquid overheating lights up.
The temperature of cooling liquid in the cooling system shall be maintained within the limits
of 85-95 °С. A thermostat with a solid filler is used to accelerate engine warming up after
start-up and automatic temperature control at various loads and ambient temperatures.
The water pump, fan and the alternator are rotated from the engine crankshaft pulley
with the help of V-belt. The lubrication in the bearing cavity of the water pump is filled during
assembly. Lubrication of bearings of the water pump is not required during the whole period
of engine operation. Engine cooling system elements of the external part of tractors "BELA-
RUS-80.1/82.1/820" are shown in subsection 3.1.3 "External part of the engine cooling sys-
tem".
Engine lubrication system is combined. The crankshaft and distribution shaft bearings,
intermediate gear bushings and fuel pump drive gears, the pneumatic compressor crankshaft
connecting rod bearing as well as valve drive mechanism are lubricated under pressure. Liners,
pistons, piston pins, rod, pushers and distribution shaft cams are spray lubricated. The oil pump
is of gear type, single section, secured by the bolts to the cover of the first main bearing.
The pump delivers oil through the pipe and cylinder block channels to a full-flow non-assembled
oil filter with a paper filter element in which it is cleaned of impurities, combustion products and
wear. From the full-flow non-assembled filter purified oil enters the radiator for cooling. From the
oil radiator oil enters the engine line.
When starting the engine, unheated oil due to the high resistance of the radiator through
the pressure reducing (radiator) valve enters directly into the engine line, bypassing the radiator.
Safety valve (valve of the full-flow non-assembled oil filter with filter element) serves to maintain
oil pressure of 0,8 Mpa. When the pressure rises above the indicated, part of the impure oil is
drained through the valve into the engine crankcase. The pressure relief and safety valves are
not adjustable. It is strictly forbidden to unscrew plugs of the pressure relief and safety valves.
The drain valve is adjusted for the pressure from 0,25 to 0,35 Mpa and serves to maintain the
required oil pressure in the main engine line. Excessive oil is drained through the valve into the
engine crankcase. From the main engine line through the channels in the cylinder block oil flows
to all main bearings of crankshaft and journals of the distribution shaft. From the main bearings
through the channels in the crankshaft, it flows to all the connecting rod bearings. From the first
main bearing through the special channels oil flows to the bushings of the intermediate gear and
fuel pump drive gear as well as to the fuel pump. Valve mechanism parts are lubricated with oil,
flowing from the rear bearing of the distribution shaft through the channels in the block, cylinder
head, boring in the IV shank of the rocker arms to the inner cavity of the rocker arms shaft and
through the hole to the rocker arm bushing, from which it flows through the channel to the ad-
justing screw and to the rod. Oil flows from the main line to the pneumatic compressor through
the borings in the cylinder block and a special oil line. The oil is drained from the compressor
into the engine crankcase.
The alternator is a non-contact electric machine with one-way electromagnetic excitation
and an integrated voltage regulator. The alternator works in parallel with the accumulator battery
and serves for its charging, as well as for direct current power supply to the consumers, installed
on the tractor.
For engines start the electric starter is used. On the engines Д-243/243С of tractors
"BELARUS-80.1/82.1/820" starters of the rated voltage 12 V are installed. The starter is a
direct current electric engine. The starter switch is remote, with the help of electromagnetic
relay and starter switch.
The pneumatic compressor is designed for compressed air injection into the compres-
sor system of the trailer brakes drive and tyre inflation. When the engine is operating in agri-
cultural work that does not require compressed air energy, the compressor has to be turned
off. The pneumatic compressor is of piston type, single-cylinder, air cooled. The pneumatic
compressor drive is carried out from the fuel pump drive gear.
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80-0000010B OM