One of the most famous cars of the VAZ plant is the Niva SUV. The car began to be produced in 1976 and, having gone through a series of upgrades, continues to remain on the assembly line under the designation 4x4 or 4x4 "Urban".
When creating the Niva car, the designers encountered a lack of an engine of suitable power. Available engines with a volume of 1.2-1.5 liters were not very suitable for a car with all-wheel drive. The situation was saved by the appearance of a larger model 2106 engine. Due to the maximum possible increase in the diameter of the cylinders, its displacement was brought to almost 1.6 liters, and the power reached 80 forces. It was this motor that became the main Niva power unit for more than 20 years.
In the mid-90s, the Niva underwent modernization, during which a number of changes were made to its design. The design of the rear of the car has changed, as well as many elements of the interior of the SUV. The 1.7-liter VAZ-21213 engine began to be used as the base power unit. Initially, the motor was developed for the upgraded machine of the seventh model, but the projectSUV turned out to be more promising.
The motor uses a block from the engine of the sixth model as the basis. But it has new pistons with an original design. Because of this, it was necessary to introduce some solutions to the layout of the block head and motor connecting rods. Early versions of the engine were equipped with a Solex carburetor (model 21073), which helped to reduce fuel consumption and reduce the amount of harmful components in the exhaust gases.
At the time the updated Niva entered the market, such a fuel supply system provided quite acceptable technical characteristics of the VAZ-21213 engine. The engine power increased slightly - only up to 79 forces, but much more important was the resulting increase in torque, which amounted to almost 125 N / m. Thanks to this, the Niva has become much better to overcome difficult sections of roads. At the same time, the engine used the most common grade of gasoline, A92, as fuel.
The main body of the engine has not undergone significant changes and was made by casting from cast iron. Such a material made it possible to obtain significant rigidity and durability of the structure at acceptable weight values. The weight of a fully equipped VAZ-21213 Niva engine does not exceed 117 kg.
The block has four cylinder bores with a diameter of 82 mm, which is the maximum allowable for the design. Attempts to further boring blocks, in order toadditional increase in volume, did not bring success. Between the cylinders there are channels spilled in the body of the block for coolant supplied under pressure from the pump. The pump itself is located in a special place - on the frontal part of the engine - and has a belt drive through a system of pulleys. The scheme of channels of the cooling system has been slightly changed due to an increase in the diameter of the cylinders.
In the lower part of the block there are five recesses for replaceable liners of the engine crankshaft bearings. Three supports placed in the central part have additional tides and serve as block stiffeners. To prevent oil leakage, the shaft is sealed at the ends with replaceable rubber seals. The lower part of the motor is covered with a sump, which contains a supply of oil for the lubrication system. The design of the pallet has a special recess in which the elements of the front axle wheel drive are placed.
The main shaft of the motor is borrowed from the power unit of the third model (with a volume of 1.5 liters). It has cranks with a rotation radius of 40 mm, which provides 80 mm stroke of the motor pistons. Additional counterweights are available on the shaft to reduce vibration and ensure more uniform operation. They are placed on all cheeks of the shaft and are made in one piece with the shaft. One of the differences between the VAZ-21213 engine shaft was a slight increase in the diameters of all shaft journals (by only 0.02 mm). This decision is dictated by the desire to reduce the oil clearance during engine operation. Reducing clearance reduces the amount of torque needed to rotate and slightly improves the overall performance of the motor.
Inside the shaft there is a special channel through which oil is supplied under pressure to the loaded structural elements. When the shaft rotates, the oil passes in the channels for additional purification from large impurities due to centrifugal force. Dirt is deposited in special holes closed with screw plugs. Cleaning of these holes is carried out during the repair of the motor.
A distribution system drive gear and a pulley are installed on the toe of the shaft, which serves to drive the pump and generator belt. Between the gears of the main and camshafts, a double-design chain consisting of 116 links is installed. To tension the chain, there is a special device with an increased length of the working element (shoe), which bends one of the side branches and selects the excess length. The pump of the engine lubrication system is driven from the same circuit. The camshaft has reshaped cams to increase intake valve opening time.
These parts of the VAZ-21213 engine are made of aluminum and are not borrowed. In the bottom of the pistons there is a special recess that acts as part of the combustion chamber, as well as two annular selections for valve plates. The tightness of the piston-cylinder pair is provided by three rings. On the bottom of each piston, a part class is indicated, which reflects the diameter of the piston and the diameter of the hole for installing the pin. Another important difference between the pistons was the same weight, whichgreatly simplifies the selection of new parts.
Engine connecting rods 21213 have a special design, due to which the strength and life of the part is increased. The connecting rod bearing insert caps are secured with specially designed bolts to prevent loss of torque during operation.
A generator is installed on the VAZ-21213 engine, which simultaneously serves as a drive belt tensioning mechanism. To do this, it has a movable support, which, after setting the interference, is clamped with a nut. The engine is started from an electric starter installed in the tide on the clutch housing.
Ignition includes a special sensor that provides ignition pulses and a coil common to all candles. The operation of these elements is controlled by the switching unit.
Since the carburetor of the VAZ-21213 engine did not allow further improvement in the environmental performance of the engine, it was replaced by the injection system. Such a power unit received the designation 21214 and a small increase in power and torque. Another direction of development was the 2130 option, which is installed on the Chevrolet Niva. To date, all three engine options with an injector remain in the series - 21213, 21214 and 2130.