Diesel engines MAN of the D2848 series are 8-cylinder 4-stroke internal combustion engines with a V-shaped cylinder arrangement at an angle of 90 degrees, direct fuel injection and turbocharging. Also, the engine has a forced lubrication of the bearings. This motor is cooled by water.
In the D 2848 engine, the crankcase is made of modified cast iron. These two elements, together with the cylinder block, form one part. Due to the fact that this block is pulled down, the engine has additional rigidity. The engine has wet replaceable liners and separate cylinder heads.
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|Engine’s type||V, diesel|
|Power output, hp (kW)||900 (662)|
|Number of cylinders||8|
|Compression ratio (compression)||15,5:1|
|Cylinder bore, mm||128|
|Piston stroke, mm||142|
|Turbine||turbo / charge air cooler|
|Timing mechanism||spur gear|
Main engine elements
The crankshaft of the D2848 engine is made in the classic version with 5 bearings and a paired counterweight. The crankshaft oil seals are radially sealed and have replaceable rotating O-rings. Camshaft connecting rods are made by hot die forging. The bearings in which the crankshaft and connecting rods rotate are made of lead bronze, which has good antifriction properties.
- Water-cooled charge air cooler;
- Oil separator valve for crankcase ventilation;
- Oil filler neck;
- Charge air cooler;
- Idler pulley;
- Water pump;
- Oil cooler;
- Oil separator valve for crankcase ventilation
- Oil filter;
- injection pump;
- Fuel filter.
A camshaft is installed in the center of the cylinder block, which has a V-shape and from 5 to 7 bearings, depending on the engine modification. The high pressure fuel pump, oil pump and camshaft drive are driven by gears. Through the transmission elements, the camshaft drives the rocker arms, which open the suspension valves located above the cylinder. The transmission elements are mushroom-shaped pushers, hardened by high frequency current and characterized by high surface hardness.
The circulating lubrication system in the D2848 uses one or two pumps (depending on model) connected to each other. A double filter is installed in the system line to clean the used oil. A feature of this system is the multiple circulation of oil from the sump through the oil cooler and filter to the main distribution pipeline. After the oil enters the pipeline, it goes to:
- rocker arms;
- piston bushings;
- camshaft bearings;
- camshaft and cylinder drive gears;
- main connecting rod bearings.
Also, oil from the circulation system enters the exhaust turbocharger and the high-pressure fuel pump. The above elements are lubricated with spray oil. The high pressure in-line plunger pump is driven via gears from the crankshaft.
Fuel enters the injection pump chamber after cleaning when passing through a double filter. The turbine wheels are rigidly mounted on the turbocharger shaft and are driven by the exhaust gases. When the compressor wheels rotate, air is trapped and fed into the cylinders, creating excess pressure. The oil for this unit is supplied from the circulating system. A regulator is attached to the front of the injection pump using a flange. Its task is to maintain the crankshaft speed. The force generated by the force of the rotating crankshaft is transmitted to the pump rack. The higher the frequency, the greater the centrifugal force becomes, which leads to a decrease in fuel delivery. The frequency is maintained automatically.
The engine uses water-cooled air that is supplied to the cylinders. the chiller is a chilled water heat exchanger that is supplied by a water pump to the circuit. The vane pump has built-in thermostats and is driven by V-belts through the crankshaft pulley. The heat exchanger and the expansion tank are combined into one housing.
Explanation of marking MAN D2848
|D||The fuel that the engine runs on is diesel|
|28||Cylinder diameter, mm: 128|
|4||Piston stroke, mm: 142|
|8||Number of cylinders|