YaMZ-3E847

In 1997, the Yaroslavl Motor Plant began production of a four-stroke V-shaped twelve-cylinder diesel engine, unified with the V-shaped eight-cylinder YaMZ-846 and the V-shaped twelve-cylinder YaMZ-847 . High pressure fuel pumps are produced at the Yaroslavl Fuel Equipment Plant .

Diesel engine, turbocharged , V-shaped, twelve-cylinder four-stroke, the purpose is to equip KamAZ-49255 cargo sports cars, but it did not live up to its expectations: with a power of 1050 hp and a torque of more than 3700 Nm, he easily broke transmission parts that were not designed for such large parameter values. Largely because of this, he was discontinued in 1998 following the results of two rally marathons.

The power system is a mechanical injection pump , one pump section per cylinder, with direct injection. Located in the collapse of the cylinder block. Intake pipelines are located in the collapse of the cylinder block. OHV valve mechanism, valves are located (4 per cylinder) in the cylinder head and are driven through the rocker arms and rods from the lower camshaft located in the cylinder block and driven through two gears located on the front end of the engine and covered by a cover. The rods have roller pushers. Crankshaft crankshaft journals are located at an angle of 60 °, which ensures uniform flashes every 60 °. Cranks are displaced. Engine cooling liquid. Cylinder liners are cast from ductile iron. All inlet and outlet valves are equipped with two springs. With a special lock, the spring plate is connected to the valve, ensuring its rotation during engine operation

The steel camshaft is stamped, the movement from the cams, individual for each valve, is transmitted by rods with roller pushers. The crankshaft is hot stamped from steel.

High pressure fuel pump (TNVD) 12-plunger, placed between the rows of cylinders. The drive is a centrifugal clutch with auto-adjustment of the fuel injection timing. All plungers are arranged in a row.

Pistons are cast from a high-silicon aluminum alloy, each has 2 compression rings and 1 oil scraper.

Type: diesel;

Cylinder diameter: 140 mm;

Piston stroke: 140 mm;

Valve mechanism: OHV (nizhnevalny, upper valve);

The order of the cylinders: 1-5-3-6-2-4-7-11-9-12-12-10;

Arrangement of cylinders: V-shaped, at an angle of 90 degrees;

Cooling: liquid;

Block Material: Cast Iron;

Power system: mechanical in-line fuel pump;

The number of measures: 4.

The design of the YaMZ-840 family of engines is characterized by the following solutions:

• individual application for each

cylinder of unified cylinder heads, which allowed to simplify the casting design, to unify cylinder heads for engines with different number of cylinders, to improve the adaptability of the engine for repair and to simplify the problem of gas joint sealing;

• the use of steel gaskets

radically solved the problem of sealing the gas joint and adjusting the piston clearance by installing gaskets of various thicknesses;

• application of pistons with relatively

a short skirt, with two compression rings and one oil scraper ring, made it possible to reduce the dimensions of the engine in height and width, increase the rigidity of the cylinder part of the block and cylinder liners, and increase the mechanical efficiency engine by reducing friction losses;

• use of cavity oil

piston cooling;

• gas distribution drive design

the fuel pump and vehicle components from the rear end of the crankshaft provides vibration protection for the engine and reduces its noise;

• application of four valves for each

the engine cylinder in order to improve filling and reduce pumping losses, profiled inlet channels providing a given twist moment of the air charge, significantly influenced the improvement of fuel efficiency of the engine;

• effective absorber installed

torsional vibrations of the crankshaft in order to reduce stresses in its elements;

• to increase the resource (more than 10 thousand

hours) crankshaft journals are nitrided;

• full flow oil applied

filters with a high degree of purification and a centrifugal oil-free filter to improve the quality of oil filtration; remote high-performance dry-type air filters prevent cylinder wear and improve engine performance;

• hydraulic or disc couplings in

the fan drive provides automatic and manual control of the fan;

• built-in applied (to the system

engine cooling) a water-to-air charge air cooler to reduce heat stress, improve efficiency and resource;

• in the process of testing the design

the optimal valve timing, the shape of the combustion chamber, the timing of the fuel injection, the elements of the fuel system are selected in order to obtain high rates of fuel economy, smoke, toxicity and noise;

• new fuel injection pumps with maximum

fuel injection pressure up to 1000 kgf / cm ² .

As of 2014, at the Yaroslavl Motor Plant (Autodiesel), diesel is discontinued.

• History of diesel engines of the Yaroslavl Motor Plant
• Engines of the Yaroslavl Motor Plant
• History of KAMAZ-49255
• YaMZ engines are V-shaped 12-cylinder . Archive of the official website of the GAZ Group]