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Engine ZMZ 406. Let there be injection!

ZMZ 406 is actually not as young as is commonly believed. Developments on a high-revving overhead engine for large vehicles began back in the USSR. Even then it was clear that with all the wonderful qualities of the engine family and its predecessors, we needed to move forward.

There were two ways:

— Leave the old block and, while maintaining the general design of the engine, work on a modern body kit;
— Create a completely new motor.

Supporters of the first scheme were found in Ulyanovsk, where the injection system would later be created. The motor is good and very convenient from the point of view of the absence of technical problems in installing it on old cars, which greatly pleased the supporters of progress in the camp of GAZ 21 owners (the motor is installed easily and naturally, joining with the original fasteners, gearbox, etc.).
ZMZ engineers, in turn, chose option number two and began designing the engine from scratch.

Creation

According to one version, the ZMZ 406 and its brothers appeared as a result of direct copying and further work to DEVORATE the B234i SAAB 9000 engine. The author of this story talks in detail about how good the original is and what a crooked copy it turned out to be, which was made perfectly during the finishing process unsuitable for use. Unfortunately, this fairly widely circulated legend does not provide any specific names, documents, or any other verifiable evidence of truth. Perhaps the only thing that could really testify in favor of this version is the external similarity of the engines and the same displacement. You can read more about this branch of alternative reality on a variety of resources, from UAZbuki and drive2, to drom and Mail’s “Answers” project. The article is the same everywhere. This information is not found anywhere else in the available sources.

We will look at a different history of the origin of this motor. An attempt to move the camshaft from the cylinder block to the head was made at the stage of work on the GAZ 21 engine, but the design turned out to be not very reliable, and the engine went into production in the lower version and retained this design until the ZMZ 402 engine. Design work on the new engine is starting at the end of the 80s of the last century. Times were not easy, and therefore the development and fine-tuning of the engine dragged on until the early 90s. The engine went into small series only in 1992. The plans were quite ambitious, and the new engine was supposed to be offered not only to the traditional partner, the Gorky Plant, but also to AZLK, BAZ and even VAZ. However, the economy was falling apart before our eyes, the factories were struggling to survive, and there was no talk of putting new machines on the assembly line. As a result, only GAZ became the consumer of the new product.
Large-scale production began only in 1996 and reached significant volumes only by 1997.

Design and features

The engine is a gasoline, four-cylinder, sixteen-valve, in-line with distributed fuel injection and a microprocessor control system. Power 145 hp at a crankshaft speed of 5200. The working volume is 2.28 liters.

The block is cast iron, the cylinders are machined directly into the body of the block. This solution made it possible to make the block very rigid, and the gaps in the friction pairs became more stable. However, the possibility of repair boring is provided (three repairs are allowed).
Closed crankcase ventilation, forced.
The magnesium cast iron crankshaft rotates in five bearings on plain bearings. Longitudinal movements of the shaft are limited by thrust half-rings installed in the recesses of the third main support. Both ends of the shaft, to the delight of car mechanics, are sealed with self-pressing rubber or silicone seals.
The pistons are cast aluminum with two compression rings and one integral oil scraper ring. The connecting rods are steel I-section, with a split lower head on a plain bearing. Piston pins are of a floating type, not secured either to the piston or to the upper end of the connecting rod. Longitudinal movement is limited only by retaining rings. The piston stroke is reduced to 86 mm. The piston diameter remains the same - 92 mm.
The ZMZ 406 engine lubrication system is full-flow, combined. Bushings, plain bearings and hydraulic tappets are lubricated under pressure, and cylinder walls are lubricated by splash lubrication. The oil pump is gear-type, single-section with a rather original drive design. Traditionally, the oil pump shaft is driven either by a gear transmission from the crankshaft, or through helical gears from the camshaft, but ZMZ engineers did not find such solutions interesting enough, and they went their own way. The drive rotates from the timing intermediate shaft, driven by a chain. It turned out to be quite cumbersome, but overall quite reliable. Motorists generally consider this innovation to be sabotage, perhaps they are right. The pressure reducing valve opens at a pressure in the system of 0.7-0.9 kgf/cm2, directing the oil to the oil cooler, from where it flows into the engine crankcase. .
The cooling system is a closed type, operating under excess pressure.

Due to the higher degree of boost, the engine is quite demanding on the quality of engine oil and requires more serious maintenance than its predecessors.
The block head is cast from aluminum alloy. The combustion chamber is tent-type with four valves per cylinder. The valve mechanism received hydraulic pushers, which saved motorists from the need to adjust the valves. The intake and exhaust manifolds are located on different sides of the head.
The camshafts are now also located in the head, there are two of them, one works with the intake valves, the second with the exhaust valves. The shafts are cast from cast iron and rotate on five bearings in plain bearings. The longitudinal movement of the shafts is limited by plastic thrust half-rings in the front cover and front supports. The shaft drive is a two-stage chain drive using an intermediate shaft. The upper stage chain has 70 links, the lower one - 90. The chain tension is regulated by automatic hydraulic tensioners with thrust shoes made of wear-resistant plastic. Subsequently, the shoes were replaced with levers with stars, which increased the service life of the mechanism between repairs. Please note that chains with different types of tensioners are not interchangeable.
The exhaust manifold is cast iron.
The intake manifold is cast from aluminum, a receiver is mounted on it, to the flange of which a throttle assembly with a cable drive is attached. The throttle is heated from the engine cooling line.
Fuel is supplied to the combustion chambers through individual injectors (distributed injection). Electronic injection control.
Microprocessor ignition system. Based on the readings of engine sensors.
Over the years, engine control units MIKAS-5.4, MIKAS-7.1, ITELMA VS 5.6, SOATE were used. Accordingly, some sensors were also changed, in particular the mass air flow sensor.

Modifications and applicability of ZMZ 406 engines

The engine was installed on cars:
Volga 3102;
Volga 3110;
Volga 31105;
Gazelle;
Sable.
In addition, the ZMZ 406 is quite successfully installed by many car enthusiasts under the hoods of Volgas of the twenty-fourth family. To do this, you have to remove the right amplifier of the engine shield (it interferes with the receiver), the wiring is changed, other indicators are installed in the dashboard, or the entire panel is changed (the fasteners do not match, but nothing that a determined person cannot handle). It is also advisable to replace the gas tank, since the operation of the electric gas pump requires an anti-drain bowl, which is not present in old-type tanks; without it, the gas pump picks up air during braking and acceleration. When replacing the tank, you will need to adjust the filler neck.
There are known cases of installing an engine on UAZ cars instead of the ZMZ 409, but such a conversion is very controversial, since an engine with a pronounced torque at the bottom is more relevant for an SUV.

There are several modifications of ZMZ 406:

ZMZ 4062.10 is an injection engine for running on A92 gasoline. Compression ratio - 9.3. Designed for installation on passenger cars.
ZMZ 40621.10 is a modification of the 4062.10 engine that complies with EURO-2 environmental standards.
ZMZ 4063.10 is a carburetor version of the engine, designed for installation on light commercial trucks and minibuses. Power reduced to 110 hp.
ZMZ 4061.10 is a carburetor engine for light commercial vehicles. The compression ratio was reduced to 8 to run on A80 gasoline. Power - 100 hp

Generalization

To date, the engine has been produced with a circulation of more than one and a half million, it is the most common engine for light commercial vehicles in Russia.
ZMZ 406 was originally designed as the basis for a whole family of new engines for a wide variety of equipment. It has a huge potential for modernization and the construction of engines with different characteristics on its basis. So it served as the basis for the creation of motors of the ZMZ 409 and ZMZ 405 families.

The disadvantages of the family include:

sagging of valve seats during long-term operation of the engine on a lean mixture or on gas fuel;
a bulky timing mechanism that does not have a very long service life (mainly, the system of tensioning the drive chains causes complaints; however, at the moment there are several sets from different manufacturers that allow you to improve this unit);
there is also a lot of criticism of the control unit from SOATE with its unreliable mass air flow sensor (problems especially often arise when using gas fuel);
and the main problem, also inherent in other modern ZMZ engines, is the very low quality of spare parts, some of them are produced using technologies the use of which in this case is unacceptable.

In general, the ZMZ 406 is a very reliable and maintainable engine, which often outlasts the body of the car on which it is installed. Of course, it is more complex, requires timely maintenance and high-quality oil, and many of its components can no longer be repaired “on the knees with a hammer.” However, if you have the appropriate tools, it does not cause any particular problems, and spare parts are widely available.

The 3M3-406 engine, in carburetor and injection versions, was mass-produced at the Zavolzhsky Motor Plant from 1996 to 2008. It was installed on cars of the Gorky Automobile Plant: Volga cars, light trucks and minibuses - GAZelle and Sobol. It is a gasoline, four-cylinder, in-line sixteen-valve engine with a DOHC gas distribution mechanism.

The 3M3-406 motor is not as “young” as is widely believed. The first developments on this revving and upper-head version, designed to replace the 402nd Zavolzhsky engine, were made back in the second half of the eighties. It was decided, despite all the wonderful qualities of the engine, its success and demand, to move forward.

There were two ways considered by the plant’s specialists: leave the old block and, while maintaining the general design of the engine, work on its modern body kit; or create a completely new motor. Both options eventually found their implementation. The first is in Ulyanovsk, where the injection UMZ-421 was created - reliable and convenient (including in the sense of the absence of technical problems with installation on old cars, in particular, GAZ-21).

At the Zavolzhsky Motor Plant, a completely new engine was actually created. It must be said that attempts to transfer the camshaft from the cylinder block to the head were made here even at the stages of work on the engine for the GAZ-21. However, that design turned out to be not entirely reliable, and the motor went into mass production in the lower version, retaining this design until the “3M3-402”.

For the first time in the domestic mechanical engineering, the 3M3-406 design used: 4 valves for each cylinder, hydraulic pushers, a 2-stage chain drive of two camshafts, an electronic fuel injection and ignition control system.

The 3M3-406 engine reached small mass production only in 1992. They began to equip Volgas of all existing modifications. Plans for the future of the new engine were ambitious: it was planned to supply “3M3-406” not only to GAZ, but also to AZLK, and even to VAZ. However, given the complete collapse of the economy, these plans were not destined to come true.

The Gorky Automobile Plant remained the only consumer of 3M3-406 engines. And the main part of the vehicles that were equipped with the engine of this model were GAZelle and Sobol trucks, and, of course, minibuses of these brands. Thanks to the increase in production volumes of these machines, “3M3-406” was launched into mass serial production in 1996, and the following year, 1997, the company reached very significant volumes of its production.

To date, the 3M3-406 engine has been produced with a total circulation of more than one and a half million units. It is still the most common engine for light commercial vehicles in Russia and the CIS. At the same time, “3M3-406” is not at all a highly specialized power unit. It was originally designed as the basis for a whole family of new engines suitable for a wide variety of equipment. Its design contains great potential for modernization and the construction of engines with a different range of characteristics on its basis. In particular, although the “3M3-406” is no longer produced, it served as the basis for the creation of more powerful and modern injection engines of the “3M3-409” and “3M3-405” families, as well as for the “3M3-514” diesel engine and its modifications .

Modifications of the 3M3-406 motor

"3M3-4062.10"– injection engine for operation on A-92 gasoline. It has a compression ratio of 9.3. Power – 150 hp For cars and minibuses.
"3M3-40621.10"– modification of the engine “3M3-4062.10”, corresponding to the environmental standard “Euro-2”.
"3M3-4063.10"– a carburetor version of the engine, intended for installation on light commercial trucks and minibuses. Power – 110 hp
"3M3-4061.10"– carburetor engine for light commercial vehicles. The compression ratio was reduced to 8 to run on A-80 gasoline. Power - 100 hp

Design and features of the device “3M3-406”

The working volume of any version of the 3M3-406 power unit is 2.28 liters (2.3). The main design features of the 3M3-406 engine are: upper (in the cylinder head) location of two camshafts, installation of 4 valves per cylinder (2 inlet and 2 exhaust).

Cylinder block

The cylinder block is cast iron. The cylinders are made with a groove directly in the body of the block. This solution provided the block with greater rigidity, and the gaps in the friction pairs are very stable. The possibility of repair boring the engine is also provided (it is permissible to make three repairs).

On the upper plane of the cylinder block of the “3M3-406” engine there are 10 threaded holes “M14x1.5” for securing the cylinder head. At the bottom of the “3M3-406” block there are 5 crankshaft main bearing supports.

The cylinder head is cast from aluminum alloy. The combustion chamber is tent-type, with 4 valves for each cylinder. The valve mechanism is equipped with hydraulic pushers, which eliminates the need for owners to adjust the valves. The intake and exhaust manifolds are located on different sides of the head.

As already noted, the innovation of the “3M3-406” design is that the camshafts are now also located in the head. There are 2 of them, and one works with the intake valves, the other with the exhaust valves. The shafts, cast from cast iron, rotate on five bearings in plain bearings. The longitudinal movement of the camshafts is limited by plastic thrust half-rings in the front cover and front supports.

Shaft drive – chain, 2-stage, using an intermediate shaft. The upper level chain has seventy links, the lower level has ninety links. The chain tension is regulated by automatic hydraulic tensioners with thrust shoes made of wear-resistant plastic. Subsequently, the shoes were replaced with levers with stars, which increased the working life of the mechanism between repairs. Chains with different types of tensioners are not interchangeable.

crank mechanism

Crankcase ventilation is forced, closed type. The crankshaft, made of magnesium cast iron “VCh60”, rotates on plain bearings in five bearings. Its movements in the longitudinal plane are limited by thrust half-rings, which are installed in the recesses of the 3rd main support. Both ends of the crankshaft, to the delight of car mechanics, are sealed with self-clamping rubber or silicone seals.

The pistons in the 3M3-406 engine are aluminum, cast, with 2 compression rings and 1 composite oil scraper ring. The connecting rods are steel, 2-T, with a split lower head on a plain bearing. The piston pins are of the floating type, not fixed either to the piston or to the upper head of the connecting rod. Longitudinal movement is limited by retaining rings. The piston stroke is 86 mm. Diameter – 92 mm.

Lubrication system

The 3M3-406 motor is equipped with a full-flow, combined lubrication system. Bushings, plain bearings and hydraulic tappets are lubricated under pressure, and the cylinder walls are lubricated by splashing. The oil pump is gear type, single-section, with an original drive design. Typically, the oil pump shaft is driven either by a gear drive from the crankshaft or by helical gears from the camshaft. And in “3M3-406” - the drive rotates from an intermediate timing shaft, rotated by a chain. It may be cumbersome, but it is reliable. The pressure reducing valve opens at a system pressure of 0.7-0.9 kgf/cm2 and directs oil to the oil cooler. From there it flows into the engine crankcase.

Due to the higher degree of boost, the engine is quite demanding on the quality of engine oil and requires more serious maintenance than its predecessors.

Cooling system

The cooling system is a closed type, operating under excess pressure, according to the traditional scheme. The coolant is pumped through the block, head and radiator. The “TC 107-01” thermostat allows circulation in a small circle while the engine is warming up, and when the warm-up temperature is reached, the thermostat opens, passing coolant through the “large circle”. The crankshaft pulley “3M3-406” transmits torque to the pump shaft, which also supplies coolant to the car’s heater, maintaining a good microclimate in the cabin in cold weather conditions.

Fuel supply system

The intake manifold is cast aluminum. A receiver is attached to it, to the flange of which a throttle assembly with a cable drive is attached. The throttle is equipped with heating from the engine cooling line.
Fuel is supplied to the combustion chambers through individual injectors (injection type - distributed). Injection control is electronic.
The ignition system on the “3M3-406” is microprocessor type. It is adjusted depending on the readings of the engine sensors. Over the years of production, in the production of the 3M3-406 engine, engine control units MIKAS-5.4, MIKAS-7.1, ITELMA VS 5.6, and SOATE were used. Accordingly, some sensors were also changed, in particular the mass air flow sensor.

Differences in carburetor and injection "3M3-406"

The carburetor “3M3-406” used carburetors of the “K-151” model. Increasing the compression ratio to 9.3 (instead of 8.2 on the engine of the 3M3-402 model) due to a combustion chamber with a central spark plug; the use of a system of distributed (alternate, in accordance with the operating order of the cylinders) fuel injection into the intake pipe using electromagnetic injectors, instead of carburetor power, ensured an increase in power and maximum torque compared to the 402 engine and the carburetor “3M3-406”. And at the same time it helped to reduce fuel consumption and reduce the toxicity of exhaust gases.

To strengthen the reliability of the “3M3-406” engines after switching to an injector, under operating conditions at higher power and higher crankshaft speeds on the engine, a cast-iron cylinder block without insert liners was introduced, which has high rigidity and more stable gaps in the friction pairs; The piston stroke was reduced from 92 mm to 86 mm, the weight of the piston and piston pin was reduced, and higher quality materials were used for the crankshaft, connecting rods, connecting rod bolts, piston pins and other parts.

The design of the engine camshaft drive is a two-stage chain, with automatic hydraulic chain tensioners; hydraulic pushers are introduced into the valve mechanism, which eliminate the need to adjust the gaps.

The use of hydraulic devices and the impressive degree of boost of the 3M3-406 engine imply high quality of engine oil purification. Therefore, the engine uses a full-flow oil filter with an additional filter element, which prevents unclean oil from entering the engine when starting a cold engine, and when the main filter element is clogged.

The drive of auxiliary units (water pump and generator) is carried out by a more reliable flat poly-V-belt.

The 3M3-406 engines use a diaphragm clutch with ellipse-wound driven disc linings. This design is characterized by significant wear resistance and exceptional durability.

The complex control system also includes functions for controlling the ignition system, allowing extremely precise dosing of the fuel supply, adjusting the ignition timing, including the detonation parameter, under changing engine operating conditions. This allows for optimal power, economic and toxic performance.

Technical characteristics and parameters of “3M3-406” in numbers

Working volume – 2.28 l;
Cylinder operating order: 1-3-4-2;
Cylinder diameter – 92 mm, piston stroke – 86 mm;
Intercylinder distance (distance between the axes of adjacent cylinders of the block) – 106 mm;
Block height (distance between the upper plane of the block and the axis of the crankshaft) – 299 mm;
Compression ratio – 9.3;
Number of valves - 4 per cylinder, 2 - intake, 2 - exhaust, total 16 cl. to the motor;
Power – 100 hp, at 4500 rpm; 110hp at 4500 rpm; or 145 hp at 5200 rpm, depending on modification (see section above);
Torque, Nm/rpm – 177/3500, 186/3500, 201/4000 (similar);
The minimum speed maintained at idle is 750-800 rpm;
The diameter of the boring of the crankshaft supports (for the main bearings) is 67 mm;
Fuel consumption - 13...15 liters per 100 km in the combined cycle;
Oil consumption for waste is 0.3% of fuel consumption;
The weight of the unfuelled engine with clutch and electrical equipment is 185, 187 or 192 kg, depending on the modification;

In 2004. The new car has undergone significant changes, but much remains from its predecessor. In particular, the ZMZ 402 and ZMZ 406 engines were installed on the new Volga from the very beginning.

Engine ZMZ 402 cross-section

Subsequently, the line of engines for the 31105 changed - since 2006, the “one hundred and fifth” models with a 2.4-liter Chrysler engine were introduced into the series, and a 2.5-liter ZMZ 405 power unit was also added.

It’s strange that this internal combustion engine ended up on a new car - you can’t equip cars with the same engine for so many years. For the first time, this engine began to be serially installed on the transition engine in 1985, and since then has not undergone virtually any changes. However, it came from the factory in 2004 and 2005.

Replacing the oil filter in the ZMZ-402 engine

But the ZMZ 402 internal combustion engine still had its advantages. Firstly, it has a lower price, and the car equipped with it is correspondingly cheaper. Secondly, car owners were captivated by the simplicity of the engine. Over so many years of production, the power unit was studied inside and out by many owners, and was sometimes repaired almost in the field.

Of all, the 402nd engine is the least powerful and low-speed. It has its own characteristic malfunctions, which are most common:

Oil leak from the rear main bearing (from the stuffing box);
Increased oil loss through the piston rings;
Broken hex drive of the oil pump;
Fallout of valve seats in the cylinder head.

If many shortcomings could somehow be tolerated, then the loss of a valve seat became a real disaster for the car owner.

Dismantling the ZMZ 402 engine

The seat most often crumbled into small pieces and scattered across all cylinders. As a result, it was necessary to change the cylinder head and piston group, and it was imperative to thoroughly clean the intake manifold and carburetor. A seat falling out is a technological defect of the factory; this almost never happens on any other engines. By the way, the 3M3 402 on the Volga 31105 was the only engine that had a carburetor system; all other internal combustion engines were equipped with an injection-type fuel system.

The undoubted advantage of the 402 is that almost any engine oil can be poured into it. In order to save money, taxi drivers went so far as to fill the engine with the cheapest Kamaz oil and M8 auto parts. Moreover, topping up was done with the oil that was on hand.

One could only wonder how this engine still worked - during disassembly, often after such operation one could observe not only carbon deposits on all internal parts of the 402, but also curdled grease of the “solid oil” type.

ZMZ 406

By the time the ZMZ 406 engine appeared on the Volga 31105, it had already been well tested on the previous model 3110, and had proven itself mainly on the positive side. ICE 406 began to be installed as standard on the Volga 3110 since 1997, and with a smaller volume (2.3 liters) it had more power and better torque. True, due to the presence of an electronic control system, the ZMZ 406 added new problems - sensors and ECUs often failed, breaks and short circuits occurred in the engine compartment wiring.

This is what the ZMZ 406 engine, ready for installation, looks like

Some malfunctions could be identified by error codes when the ignition was turned on, but the average vehicle user was unable to deal with the electronics on their own. Diagnostics are mainly carried out by Volga car owners with the 406th engine at a specialized service station.

The 406th had its own “sores”:

Chains and other parts of the gas distribution mechanism wore out relatively quickly;
The hydraulic timing chain tensioners often jammed;
Electric remote fuel pumps periodically failed;
At the slightest overheating, the head gasket burned out, and the head itself often warped.

The design of the ZMZ has not thought through the design of the timing chain tension. The extension of the upper chain shoe has a large load and often breaks off.

Timing chain on the ZMZ 406 engine

Breaking it off causes a lot of problems:

Firstly, its remains have to be drilled out of the cylinder block;
Secondly, the chains break, and labor-intensive repairs have to be made.

Technical characteristics of the ZMZ-406 engine

PARAMETER	MEANING
Configuration type	in-line
Volume, cubic m	2.28
Cylinder diameter, mm	92
Number of cylinders	4
Valves per cylinder	4
Piston stroke, mm	86
Cylinder block material	cast iron
Compression ratio, atmospheres	9.3
Cylinder head material	aluminum
Fuel system	injector or carburetor
Control block	Mikas
Fuel type	Petrol
Lubrication system	combined, with automatic temperature regulation
Power, hp/rpm	145/5200
Torque, Nm/rpm	200,9 /4500
Fuel	92
Environmental standards	Euro 3
Fuel consumption per 100 km, l
- city	13.5
- track	-
- mixed	-
Oil consumption per 1000 km, g	up to 100
Weight, kg	192

A four-cylinder engine with an in-line arrangement of cylinders is made according to the classical design, characteristic of the power plants of the Zavolzhsky Motor Plant, this is how you can begin to characterize the 406 engine. The working volume is 2.28 liters.

The combustion chamber is distinguished by the central location of the spark plug. The timing belt of the ZMZ 406 is made in a rather original way, which made it possible to compactly arrange the main elements of the power system.

The crankshaft rotation speed at maximum power is 5200 rpm, and maximum torque is observed at significantly lower rpm, which is 4000 rpm. per minute The 406 engine maintains a minimum speed of around 750-800 rpm at idle.

Design features of the 406 engine produced by ZMZ

The engine from the Saab 900 sports car was taken as a prototype for the project. The first ZMZ-406 gasoline engines appeared in the early eighties of the last century.

ZMZ-406 has some features:

The block is cast from cast iron. It is, of course, heavier than aluminum, but the use of this metal eliminates the need for replaceable liners (cylinders). In this regard, the rigidity of the structure has increased.
Two ZMZ 406 timing belts (gas distribution shafts of the intake-exhaust system) are installed in the upper part. Each of the shafts is responsible for either the intake of a fresh charge of the working mixture, or for the release of exhaust gases.
There are four valves in the head for each cylinder. That is, sixteen valves are installed on the entire four-cylinder. This amount increases the efficiency of purging the cylinder when releasing exhaust gases and increases the coefficient of filling the cylinders with fresh working mixture.
A special innovation was used for the first time on this power unit - a hydraulic chain tensioner. It made it possible to maintain optimal tension in the ZMZ 406 timing drive. This technical solution was later repeated in dozens of other designs. But the ZMZ 406 timing belt was the first-born in the domestic engine industry where this was applied.
For this engine, options were thought out to reduce the piston stroke, which is only 86 mm, while the cylinder diameter is 92 mm. This approach made it possible to increase the compression ratio to 9.3. This is a very high value. But the theory states that as the compression ratio increases, the efficiency of the power plant also increases. The short stroke movement of the piston promotes better filling.
ZMZ 406 is solved according to the traditional scheme. The coolant is moved by the ZMZ 406 pump through the block, cylinder head and radiator.
There is also a feature - a flat poly-V-belt is used, eliminating the possibility of an unexpected break.
The ZMZ 406 thermostat allows you to organize circulation in a small circle during the warm-up period of the engine, and when the warm-up temperature is reached, the thermostat opens, releasing coolant in a large circle.
The ZMZ 406 crankshaft pulley transmits torque to the shaft of the ZMZ 406 pump, which supplies coolant to the car’s heater, maintaining an optimal microclimate in the cabin during the cold season.
The coolant temperature sensor helps the driver to constantly monitor the temperature.
The 406 engine is not without a lubrication system. A gear pump moves the engine oil from the oil pan and supplies it under pressure for cleaning, where impurities larger than 40 microns are removed in the ZMZ 406 oil filter. Purified oil is forced into the channels of the ZMZ 406 crankshaft, moving inside the main and connecting rod journals, providing stable lubrication in these units, which experience enormous alternating loads. Some of the oil under pressure moves further, lubricating the piston pin. Then the oil gets onto the surface of the piston. The piston interacts with the cylinder mirror of the ZMZ 406 engine through an oil film formed in the contact zone.

Difference between injection and carburetor fuel systems

During the first decade of production of the ZMZ 406 engine, the carburetor was responsible for preparing the working mixture. Now an injection modification of this engine is being produced.

The use of an injector made starting easier, improved throttle response and reduced fuel consumption. What is the reason here?

From the theory of internal combustion engines it is known that increasing carburetor performance depends on the crankshaft speed. The consumption of the combustible mixture increases as this indicator increases. A sharp press on the accelerator pedal leads to an increase in the relative content of gasoline vapors in the ZMZ 406 carburetor. The excess air coefficient is slightly reduced, which leads to an increase in torque and an increase in the crankshaft speed.

The ZMZ 406 engine injector works somewhat differently. The microprocessor helps here, which clearly responds to the position of the control pedal. If it is necessary to increase the speed and lightly press the pedal, more fuel is injected into the cylinder. The time interval between the load and its correction in any injection engine is reduced several times. This increases throttle response and improves the dynamics of the Gazelle or Volga (depending on which car the ZMZ 406 injector is installed on).

The main reason for the high performance of the injection system compared to the carburetor system is the absence of jets, which regularly become clogged.

This led to the need for periodic purging, and often mechanical cleaning of small-diameter holes. Of course, if the injection system fails on the road, not every driver will be able to fix it on their own.

Engine tuning

Tuning ZMZ 406 is a way to change the output data. Many drivers are looking for ways to improve the performance of their cars.

Some are not satisfied with the available power, others are embarrassed by the gluttony of the engine, others simply want to distinguish themselves by choosing one or another option that they want to optimize.

The first thing powertrain specialists do is increase power:

You can simply bore the cylinder and use larger diameter pistons. But this path is fraught with a decrease in the strength of the block.
More often they go the other way - they force it by increasing the air supply using mechanically driven turbines or using turbocharging.

The first way is simpler, but it should be taken into account that it is necessary to create a mechanism with a high gear ratio - the turbine speed is at the level of 10-15 thousand revolutions per minute. Such a drive, boosting the engine, creating tuning of the ZMZ 406, is difficult to perform. More often they go the route of using a turbocharger.

The turbocharger uses exhaust gas energy to operate. ZMZ 406 turbo, a gas inlet to the turbocharging system is installed on the exhaust part. There is also a compressor on the same shaft with the turbine, which pumps a clean charge of air into the cylinders of the ZMZ 406 engine. The filling increases. The cyclic fuel supply increases proportionally, which leads to an increase in the amount of working mixture in the cylinder, and, accordingly, the gas pressure also increases, which leads to an increase in torque. Further, the power also increases.

The theory of internal combustion engines states that an increase in power during turbocharging is accompanied by a decrease in specific fuel consumption. ZMZ 406 tuning in this way allows you to improve not only the dynamics of the car, but also improve its efficiency.

In the eighties of the last century, another direction of supercharging was studied - this is dynamic supercharging, the essence of which was to select the parameters of the intake system so that the pulsation frequency of the air flow at the intake corresponds to the resonant frequency of the system itself.

Mathematical models were proposed to allow one to calculate the optimal diameters and lengths of the intake system. A number of specialists also installed mechanical resonators, which, through special membranes, transmitted impulses from the exhaust system to the intake system. This path allows you not to change the 406 engine radically, but at the same time achieve an increase in power and a decrease in specific fuel consumption.

The ZMZ 406 engine can be modified even more simply. It is enough to polish the inlet and outlet channels in the power system. This optimization, when combined with a GAZelle 406 engine, allows for improved dynamics. The combination of ZMZ 406 on a UAZ with polished channels will pleasantly surprise the user; the car will pleasantly resemble an energy-rich passenger car.

Popular mistakes made by motorists

The pursuit of increased power for some motorists comes down to just reworking the ZMZ 406 engine. But not all modifications are good. And some are harmful, this is what reverse tuning or anti-tuning consists of:

There are rumors on the Internet that you can increase engine power by reducing the mass of the flywheel. At the same time, the authors point out that the flywheel takes away power and increases the weight of the engine. In fact, the flywheel stores the energy that this engine receives during the “power stroke” to complete the remaining cycles in a four-stroke engine. As the number of cylinders increases, the relative mass of the flywheel decreases, but this occurs due to a change in the number of power strokes per revolution of the crankshaft, since more pistons are involved in the work. Ideally, if you increase the number of working cylinders to infinity, then the flywheel will not be needed at all.
There are experts who recommend installing air swirlers in the intake system. But such specialists do not understand that when the air flow moves, a turbulent flow regime is observed. Turbulence by definition is a movement with an eddy flow, as Bernoulli proved more than 150 years ago. Excessive interference will only reduce the amount of air charge and reduce power, which will also affect the efficiency of the engine.
Recently, ideas have also appeared to heat the air at the intake - they say that the 406 engine will have an injector increase in power. But this is not true. The air charge density decreases with heating and constant pressure. Consequently, its total quantity decreases. And this leads to the fact that the pressure drops during combustion of the mixture, and instead of increasing, the power decreases.
There are also authors who have been saying for more than forty years that water should be fed droplets into the intake tract of the ZMZ 406 injector. But remember that designers are looking for ways to separate fuel and water so that the combustion process is more intense. Water entering the cylinder at high temperatures will begin to cause intense corrosion. When fuel burns, the exhaust gas contains carbon monoxide and water vapor. Those who have been using motors for quite some time know that the ZMZ 406 engine does not need to use ways that impair its reliability.
There is also a group of “specialists” who recommend optimizing the engine by replacing the hydraulic chain tensioner. They advocate installing an electric tensioner, and the circuit diagram of the vicious device should be purchased from them for a lot of money. It’s already absurd to pay to ruin the power plant.

Therefore, when listening to the advice of various experts, you should remember that designers do not understand their business much better than ordinary people. It’s not for nothing that they refuse many ideas that will ruin the engine.

Which cars use the ZMZ-406 engine?

The modern engine of the Zavolzhsky Motor Plant, model 406, is installed on GAZ-3110 Volga passenger cars and 3302 trucks.

Motor and automobile plants in the Nizhny Novgorod region constantly monitor their products and collect information on the operation of the equipment produced.

Of course, sometimes certain conflict situations arise.

They are related to the fact that drivers address the following questions:

troits Gazelle engine;
timing marks are not visible;
injectors fail;
the pump fails;
ZMZ piston;
the oil filter is leaking;
The thermostat is unstable;
basic technical characteristics and others are not maintained.

Manufacturers always try to provide assistance through their service centers, which are scattered throughout Russia and the CIS.

Today, the most popular engines for the Gazelle are the ZMZ-406 with a displacement of 2.3 liters, which since 1996 began to gradually replace the ZMZ-402 engines. Back in 1992, a small series workshop was opened at the Zavolzhsky Motor Plant, in which pilot production of engines of the new ZMZ-406 family was organized. And the first sketches were made by the designers with the approval of the then existing Ministry of the Automotive Industry of the USSR. The thought that has been itching the brains of many operators since 1970 is “why can’t we make a big Zhiguli engine for Volga and RAFik?” - was embodied in cast iron and aluminum. Although, of course, upon closer examination there is nothing in common between them; the ZMZ-406, rather, is simply similar to any good gasoline engine of that time. And it is not very outdated today. It became the first electronically controlled injection engine of this class in Russia, and even with a 16-valve twin-shaft head. As a curiosity today, I remember the story of the car being inflated to 150 liters. With. power of Volg engines (how much money was overpaid on taxes...), but overall the engine turned out to be very playful. For a long time, only carburetor versions ZMZ-4061.10 and ZMZ-4063.10 were installed on the Nizhny Novgorod lorry, developing 100 and 110 horsepower, respectively.

Contrary to expectations, the engine retained the traditional maintainability of ZMZ engines. The crankshaft is ground in three sizes every 0.25 mm, the cylinder block can be bored twice with an increase of 0.5 mm. The cast iron block is not as sensitive to “scorched” antifreeze as the aluminum one in the ZMZ-402, and the absence of liners only added rigidity and eliminated possible coolant leaks. In the early 90s, ZMZ specialists managed to presciently predict the development of trends in engine repair that emerged ten years later. As they looked into the water - a ZMZ engine with a block bored to the last size is usually installed on a Gazelle, moving under its own power to a scrap metal collection point. Everything on it is already worn out, no one needs it for nothing, but the engine is still alive.

Oil starvation ZMZ-406

Like all modern engines, the ZMZ-406 family turned out to be very demanding on the quality of the oil used. Unfortunately, many carriers ignored the factory's recommendations. After all, the “406th” engine is more picky in the oil menu than the ZMZ-402, which was content with the standard group of oils with API code SE and SF, or, in our opinion, with the “G” performance properties group, such as M10Gi, M12Gi, M5z/10G. Perhaps, with more frequent replacement intervals for oils of this group, the quality would be sufficient, but it is worth remembering that in the late 90s the market was full of extremely low quality fuels and lubricants. So the “oil pirates” contributed to the creation of a negative image of the ZMZ-406 engine.

When changing the brand of oil and manufacturer, and even more so when switching to oil of a different base, viscosity or quality, it is advisable to flush the engine lubrication system. However, the ZMZ-406 engine has approximately 300-350 g of oil remaining under the valve cover, near the valves and in the oil channels of the block head. Half of this amount can be removed by unscrewing the plug in the head near the pressure sensors. When switching to synthetics, along with the costs, the mileage until the next replacement increases to 15–20 thousand km, which slightly compensates for the investment. Well, it’s better not to use numerous oil additives, but to rely on the quality of the base oil. It contains all the necessary additives for long-lasting engine operation.

For the new family, in the design of which hydraulic valve lifters and hydraulic timing chain tensioners were used, it is recommended to use improved quality oils with API code SG, SH, SJ and not skimp on the oil filter. After all, metal particles or deposits, falling into narrow channels or gaps between mating parts of less than half a millimeter, clog them and disable delicate hydraulic devices. The failure of one or more valve lifters is immediately noticeable by a characteristic loud and frequent knocking noise under the valve cover. Of course, this knocking will not lead to immediate or major damage, but you should not drive for a long time with such a malfunction. After all, an empty hydraulic tappet will not fully open its valve, which means the engine will lose power. In addition, excessive shock loads on the camshaft cam also do not add to its lifespan. To eliminate the knocking, it is necessary to replace the hydraulic compensators, and this is not a cheap pleasure. Those carriers who did not skimp on oil, filled with semi-synthetics or synthetics of the required quality, did not know grief with new engines, especially if they were lucky with the quality of the hydraulic tensioners and hydraulic compensators themselves.

Pitch and life of the ZMZ-406 chain

Alas, the hasty launch of this motor into production did not have the best effect on its quality and service life. Of course, there were also some engines back then that had run 200 thousand kilometers or more, but in general problems arose much earlier. At that time, the Achilles heel of the new promising engine was the precision plunger pair of the timing chain hydraulic tensioner. There are two of them in ZMZ-406, each working on its own circuit. Those tensioners that went to the ZMZ conveyor turned out to have an excessively large step in moving the pusher before the next fixation. It was almost three millimeters, and contamination or insufficient precision in processing precision pairs led to jamming of the hydraulic tensioner. At the same time, vibration damping of the driven branch of the circuit was not provided to the required extent. Impact loads increased, which caused premature wear of the tensioner parts and the plastic shoe. If the driver did not pay attention to the noise that arose, almost the rumble of a weakened chain, and continued driving, then the shoe would collapse. And then, depending on your luck. In the best case, the chain jumped over the teeth of the sprockets, the valve timing was lost, and the engine stopped. It’s good that the designers took care to make holes in the pistons for the valve plates - they didn’t bend. In this case, the repair was reduced to restoring the phase settings and replacing or “recharging” the hydraulic tensioner. If the chain broke, then the front aluminum cover often also became deformed, and it was necessary to buy it. Because of such a trifle, flights were disrupted, the car was stuck against the fence for a day or two. The most annoying thing is that breakdowns occurred on a relatively young engine, with a mileage of only 30–40 thousand kilometers. Often, installing a new hydraulic tensioner gave only a temporary result, then everything happened again. Craftsmen even began to adapt collet spring tensioners from the VAZ-2101 engine to ZMZ406 engines - adjusting the chain tension once every 15–20 thousand kilometers was not difficult. The Moscow company SET went even further; its designers developed their own version in the late 90s and installed a tension sprocket on the Zavolzhsky motor instead of a plastic shoe. A similar scheme was used on Ufa Moskvich-412 engines, and in the 80s, athletes put an asterisk on the Zhiguli engine. In the last five years, the situation with hydraulic tensioners has changed for the better. Alternative manufacturers of this unit have appeared; there are already several varieties of them. There are six main designs of hydraulic tensioners for ZMZ-406, and in total there are over one and a half dozen options, there are even gas-filled ones. In 2004, the Zavolzhsky plant abandoned the use of plastic tensioner shoes, and sprockets took their place. It turned out to be quite reliable, although they were made somewhat carelessly - the sprocket bearing had a lot of play, and its bracket seemed to be bent by hand.

OPINION

CONSTANTINE RUKHANI Executive Director of OJSC "ZMZ" - In 2008 - 2009, we plan to carry out a complex of R&D and technological preparation of production aimed at further modernization of gasoline engines of the ZMZ-405 and ZMZ-409 family, primarily in order to comply with European standards 4. As is known, they are introduced in Russia on January 1, 2010. Since July 2007, the plant has been conducting development work on ZMZ 514.32 diesel engines. To comply with Euro-3 and Euro-4 standards, instead of mechanical fuel injection pumps, we equipped these engines with electronically controlled Common Rail fuel equipment manufactured by Bosch. By August-September 2008, it is planned to create prototypes of gasoline and diesel engines of Euro-4 class and begin testing. It is planned to invest about 130 - 150 million rubles for R&D on all engines in 2008. During 2009, production will be prepared for the production of these engines.

Family Affair

In general, in comparison with the ZMZ-402 engine, the “four-sixth” is a more compact engine, and the inter-cylinder distance, the diameter of the crankshaft journals and piston pin have become smaller, but have not lost in service life. The ZMZ-406 engine became the ancestor for other engines in the family, maintaining the unification of design and technology. In particular, all ZMZ-406, 405 and 409 engines have the same block height from the crankshaft axis to the plane of the connector with the head, the same connecting rods, and the difference in the crank radius is compensated by changing the distance from the piston pin axis to the piston bottom. For Gazelles, the main advantage of the ZMZ-405 and ZMZ-409 engines with a displacement of 2.5 and 2.7 liters is greater torque: 215.8 N.m and 235.4 N.m at 4000 rpm. Compared to the old ZMZ-402, it is 23 percent larger. But only ZMZ-405 engines were installed on the Gazelle; for a combination of reasons, the more powerful ZMZ-409 was not supplied to the Gorky Automobile Plant. The installation of Brazilian-assembled Chrysler engines on Volgas and Gazelles is a partial alternative to ZMZ engines.

Improving the service life of ZMZ-406: new trends

Since January 2008, the production of ZMZ-406 engines has been discontinued, although they will be used for a long time on already produced cars, and engines that meet Euro-3 standards are coming off the assembly line. These are injection modifications ZMZ4052.10 and ZMZ-4092.10. Carburetor versions are produced only for the secondary market and upon request to complete export deliveries to those countries where environmental requirements are less stringent. For operation in Russia, only the 405th engine is installed on the Gazelle. Moreover, in addition to the fuel injection system, the engines have undergone a number of significant changes aimed at increasing their service life.

The old ZMZ-405 block is easily recognized by the transverse slots about 2 millimeters wide between the cylinders at the surface of the connector with the head. These ducts in the cooling system jacket improved heat removal from the cylinder walls, but at the same time reduced the rigidity of the upper part of the block. Even when the head bolts were tightened to the required torque, the cylinder walls were somewhat deformed. If they tightened it “by eye”, and even with a good wrench, then the deformations increased. Changes in geometry affected the service life and increased oil consumption due to waste. No such deformations were observed on the ZMZ-406 engine, because the inter-cylinder bridges of the 406 block, in comparison with the ZMZ-405, are thicker: 14 mm versus 10.5 mm.

To eliminate deformations in the new ZMZ-405 block, the threaded part for the head bolts was made 24 mm longer, and the inter-cylinder ducts were hidden deep in the block. They can only be seen in cross-section.

With the introduction of Euro-3 standards, the block head also underwent modernization. With the use of an electronically controlled throttle, there is no need for idle system channels and hoses for heating the throttle assembly with coolant. Therefore, it will not be possible to install the old head on a new cylinder block. Moreover, the previous head gasket made of non-asbestos material was replaced by a metal one, imported from Erling Klinger. It is two-layer, similar to those used on modern passenger diesel engines; with a lower bolt tightening torque, it ensures reliable sealing of gas joints, as well as channels of lubrication and cooling systems. The thickness of the new gasket is almost a millimeter less than the old one; to compensate for this size, the pistons were made half a millimeter lower.

It is no secret that domestic engines differ from many foreign cars in increased oil consumption. Of course, in terms of oil consumption, the ZMZ-406 engine cannot be compared with the ZMZ402. That one was really gluttonous. The oil seal packing of the rear main bearing alone is a tribute to Ford traditions; it has been drinking the blood of its operators since 1932. The crankshaft on the ZMZ-406 was immediately sealed with lip seals, and the front one is located on the outside of the cover - if necessary, replacing it will not be difficult. Contrary to the expectations of pessimists, valve stem seals hold oil and do not allow it into the combustion chamber. They are unified with the Zhiguli ones; over more than 30 years, they seem to have learned how to make them - they don’t tan as before. Modern piston rings also contribute to reducing oil consumption; recently Czech-made rings from the Buzuluk company have been installed. The knock sensor helps keep them intact and prevent the destruction of the jumpers on the pistons - it adjusts the ignition setting. Although our operators do not like electronics, much less trust ours, they still have some use for them.

And yet there are no limits to perfection. Now, in order to reduce oil consumption due to waste, the plant has changed the technology and parameters of cylinder honing. To prevent the motor from sweating at joints sealed with gaskets, imported ones began to be used. The oil pan gasket, previously made from a rubber-cork mixture, was replaced with a metal one from Erling Klinger with an elastomeric sealing contour and T-shaped joints at the interface with the front cover and oil seal holder. If, when repairing an engine, a new gasket is not available for sale, you can use an old-style gasket; they are interchangeable. The front engine cover has been seriously changed,

On top, its fasteners were supplemented with two more holes for tighter contact with the block head. In addition, a platform was made on the cover for installing an automatic tensioner for the poly-V-belt of attachments. Its resource should be about 150 thousand kilometers. It was high time to make such a tensioner long ago - due to the poor design of the old roller, it took three hours to replace the belt. The difficulty of replacement, contrary to expectations, was not compensated by the service life of the belt. Imported ones last approximately 40–50 thousand km, domestic ones last less - from 10 to 30 thousand kilometers. Severe wear is observed in winter - due to temperature changes, transverse cracks appear. If the belt begins to fray with a frame thread, then it touches the crankshaft position sensor, and at high speeds it simply knocks on it. And then depending on your luck: either the wires going to the sensor break, or the sensor itself fails. In any case, the ignition system stops working and the engine stalls. With the installation of a new roller, the length of the serpentine belt also changed; with an engine without a power steering pump, it was 1220 mm, and became 1275 mm long. On motors with hydraulic boosters, the belt has grown to 1413 mm.

Be that as it may, the current ZMZ engines for the Gazelle are the same “tit” in the hands of the carrier, which is undoubtedly better than any “crane”.

Of course, the slowness with which the engines cured childhood illnesses is typically Russian, but please note that there are not so many factory defects, and the number of positive reviews from operators about these engines is steadily growing. A mileage of 300–400 thousand kilometers without major overhaul ceases to amaze, but these engines are already old, they have only been slightly affected by modernization. The younger ones should be even stronger. There is no reason to complain about the lack of spare parts - there are any and in every outlet. GAZ and ZMZ have never cared so much about their quality before, and the fight against counterfeit goods is being waged not in words, but in deeds (See “Flight” No. 3 for 2008, “Left bias”). And while the requirements for dealers are becoming more stringent, the network of service centers is growing and expanding.

OPINION

EDUARD BOGOMOLOV Head of the Autoline production and technical support department, Moscow - Now we have very few Gazelle buses with the new ZMZ-405 engines at our enterprise, so there is almost no information on them. The same cannot be said about its predecessor, the 406 engine - we have plenty of minibuses with such engines. Unfortunately, it is difficult to make any comparisons with other power plants. Yes, there are diesel engines, but not many of them were produced, and we did not purchase such Gazelles, fundamentally working with gasoline ones, especially since they have proven themselves very worthy. After all, it often costs tens of times less to repair them than, for example, Ford engines, and the turnaround time is also faster. And their resources in our conditions are comparable and amount to about 300 thousand kilometers. Although, according to official statements from Ford, the minimum mileage of their unit should be 350 thousand kilometers. And not every mechanic can repair a failed imported engine, despite the fact that ZMZ-406 has long been learned to be repaired in any workshop.

SPIRAL OF EVOLUTION

In 2005, the Ulyanovsk Motor Plant (UMZ) became part of the GAZ Group and continues to produce engines for UAZ and Gazelles. Own engine production in conditions of fierce competition allowed the GAZ Group to gain some independence from suppliers and gain additional profit. Motors are supplied not only to the GAZ assembly line, but also to spare parts, and this is a very capacious market. Let us note that the goal of replacing ZMZ engines with UMZ engines on the assembly line of the Gorky Automobile Plant is not pursued. This year it is planned to produce only 20,000 engines for Gazelles, about 10% of the requirement, and they only complement the current set of power units.

UMZ engines: era 92x92

Of all the engines currently installed on the Gazelle, the Ulyanovsk UMZ421 has the longest life. It is based on the Volga GAZ M-21 engine, which was put on the assembly line back in 1956. Of course, during this time it was modernized several times, but the inter-cylinder distances of the block, the diameters of the main and connecting rod journals still remained unchanged. But by and large: connecting rods, camshaft and crankshaft, oil pan, and the external appearance of the block cannot be confused with any other engine. And it all started in the late 60s and early 70s with the production of “loaves” and “tadpoles” UAZ-451 and UAZ-452, as well as all-terrain vehicles UAZ-469, initially they were equipped with a pure Volgov engine. Due to the loads associated with off-road driving, as well as the considerable mass of the gearbox and transfer case assembled together, the flywheel housing cracked and shattered in half. Several ventilation holes served as stress concentrators, and we learned how to modernize the crankcase on the ZMZ-24 engine. At the same time, instead of coarse and fine oil filters (a “pan” with a cardboard replaceable element connected to the block by frequently torn hoses), a full-flow oil filter from a Zhiguli was installed. This immediately increased the service life of the engine, and this solution turned out to be more successful than even on the ZMZ-24, although further modernization was carried out with an eye on the Zavolzhsky Motor Plant. They weren't competitors then. The crankshaft was changed - the main liners became the same width, and their covers were made of cast iron, the temperature compensation slot was removed from the piston skirts, a closed crankcase ventilation system was introduced, and the collectors were made “round” in cross-section. The next modernization took place in the late 80s; in the early 90s, the engine received the designation UMZ-417. By this time, in the Volga region they switched to the production of ZMZ-402 engines, and the ZMZ-24 block head went to the Ulyanovsk residents, it became possible to install two-chamber carburetors, and the power increased. We installed an oil pump with increased performance, with a larger gear diameter - the oil pressure became more stable in all modes. Thanks to this, “advanced” repairmen stopped putting a nut under the pressure reducing valve spring, and the motor turned out to be less sensitive to wear in the shaft joints.

All this time, somewhat outdated design solutions and technologies from ZMZ were transferred to the Ulyanovsk motor plant, and it lagged behind in modernization. But on the UMZ-417 engine, Ulyanovsk designers still overtook their mentor colleagues, given the low quality of our rubber products, they moved the front crankshaft oil seal to the outside of the cover.

Motor UMZ-421: end of packing

In the mid-90s, a UMZ-421 motor was installed on a production line in Ulyanovsk. To the delight of the operators, it had an oil seal instead of an asbestos cord, and for this reason the flywheel mount was changed on the rear axle of the crankshaft. From the plant’s point of view, the main event was the use of pistons with a diameter increased to 100 mm, this was done in order to increase power and torque. Compared to 2.5-liter engines, torque increased from 170 to 220 Nm, and power from 90 to 115 horsepower.

By this time, in the Volga region, 16-valve ZMZ-406 engines were already being produced, the Ulyanovsk residents had nothing to cover, and then they remembered that on the distant ancestor - the GAZ-M21 engine for the KGB, they installed a “Tchaikovsky” piston with a “hundredth” in diameter. But in those days, blocks were cast into the “earth” and they did not spare aluminum - the walls were very thick, in addition, the sleeve was installed along the upper and lower chords. The block remained rigid even with oversized liners. And the current casting is no match for the previous one - aluminum is in short supply, so the UAZ-421 decided to abandon replaceable liners and pour them into the block forever. That is, they created a new cylinder block. It would seem like a convenient opportunity to abandon the ancient and capricious oil pan with four gaskets and lower the connector below the crankshaft axis. Make the block stiffer and reduce the likelihood of oil leaks. But no, everything remains the same. Another miscalculation was revealed during the operation of new engines, when the time came to bore the liners. Not every machine had a “trunk” of the required length; if it was not enough, and the stroke was insufficient, the head studs had to be unscrewed. This was never done on old engines with replaceable liners. It was not always possible to screw them back in securely after repair; when tightening the heads, there were often one or two that crawled out of the block. I had to remove the head and cut an enlarged thread in the block - if I could find taps of that length! But you could pour ten long steel cage nuts into aluminum and secure the head with bolts. Another problem was related to the fact that in the area of the gas junction of the block and the head, due to the peculiarities of filling the liners, there was a layer of aluminum alloy of the block on top of their shoulder. It burned out when the engine was running even with a slight detonation ringing; it is known that the larger the piston diameter, the higher the tendency to detonation. While the UMZ-421 was installed only on UAZs, and even in the version “for 76 gasoline,” the miscalculation was unnoticeable. What kind of mileage can there be on all-terrain vehicles... The most serious tests awaited the engine after it began to be installed in some modifications of Gazelles in 1998. Here one thing superimposed on the other: increased load, high mileage and city traffic jams, causing engine overheating. As a result, the image of the motor among carriers was significantly undermined.

At the same time, everyone admitted that it simply had locomotive traction at a speed slightly higher than idle. This is an undeniable advantage of UMZ motors. These engines, unlike the Volga engines, still use a large-diameter flywheel, which makes it possible to place a clutch capable of transmitting higher torque. And good torque characteristics play a paramount role for a truck engine. The clutch basket, which traces its origins to the GAZ-51 - rigid, with peripheral springs and eternally dangling legs, has long given way to a modern one with a leaf diaphragm spring. Nowadays, the basket most often installed is from the German company Luk; according to most carriers, it goes better than others.

There was no case when operators complained about the timing drive by gears and yearned for chains, and even more so for a toothed belt. The gears are enough for 300–400 thousand kilometers, the cases of breakdowns can be counted on one hand - why look for an alternative to them. Usually the first, or even the second overhaul on the ZMZ-402 and UMZ-417 engines was done without replacing the camshaft, pusher cups and gears. The only problem that occurs in the timing drive on Ulyanovsk engines and was previously inherent in ZMZ-402 engines is breakage of the rocker arm axis when the fastening studs are weakened, failure of the fine threads in the adjusting screw, and interruption of the supply of lubricant to the upper tip of the rod. By slightly changing the design, all this can be eliminated.

OPINION

Igor Ganin General Director of Green-Eyed Taxi LLC, Tolyatti - In 2004, we purchased ten Gazelles with UMZ-4215 engines, but they proved to be extremely unreliable. Thus, due to the destruction of the pistons on two engines, the connecting rods pierced the cylinder block. This cannot be attributed to gas fuel, since the “fist of friendship” also showed an engine running on gasoline. In order not to suffer losses due to transport downtime, it was decided to replace the Ulyanovsk engines with time-tested ZMZ402. Now on the balance sheet of our automobile enterprise there are “Gazelles”, equipped only with ZMZ-405 and ZMZ-406 engines.

The wind of change

And the plant has a desire to modernize engines, but not of its own free will - competition between light truck manufacturers is now fierce. “The GAZ Group, which UMP has been part of since 2005, is being pressured not only by the Europeans, Koreans and Chinese with diesel engines (no doubt, to varying degrees), compatriots also do not guarantee the peace that was before. “SeverStal Auto” is going to seriously squeeze out “Gazelle” in the market with its FIAT Ducato and light-duty Isuzu, assembled in Yelabuga, and in Semenov, Nizhny Novgorod region, they are launching the production of IVECO Daily (See “Flight” No. 2 for 2008 “New well of Samotlor”).

Russia's transition to Euro-3 standards required the abandonment of carburetors in the power supply system of Ulyanovsk engines and the use of electronically controlled fuel injection. The plant equips UMZ-4216 engines with fuel equipment from Bosch, and, according to experts, they will even cope with promising Euro-4 standards. After modernizing the power system, Gazelle engines with UMZ-4216 engines became more economical, consumption is 14–16 liters per 100 km when operating in mixed mode, versus 16–18 liters for the previous carburetor modification UMZ-4215. The maximum power of the engine intended for installation on the Gazelle is 125 hp. s., and the torque is 240 N.m, which has a positive effect on the dynamics of a loaded vehicle. In parallel with improving environmental performance, work was carried out to improve engine reliability, build quality and increase service life. In fine-tuning the power units, UMP engineers were assisted by experts from the English company Ultra Motive. Along with the modernization of the UMZ-421 engine, the plant is carrying out work to fine-tune the design and technology for putting on the conveyor in the future a new overhead 16-valve UMZ 249 engine with an aluminum block and maintaining a working volume of 2.89 liters. Ulyanovsk residents plan to begin its production in 2010.

OPINION

Evgeniy Berezin chief designer of the Ulyanovsk Motor Plant - UMZ 4216 (Euro-3) engines, tested in 2006, differ from Euro-2 engines in the accuracy of diagnosing the crankshaft position and misfires. This was achieved thanks to a new crankshaft damper design with a rigid connection between the crankshaft and the timing disc. The control system uses an absolute air pressure sensor with a temperature sensor instead of an unreliable mass air flow sensor. This made it possible to simplify the accounting of air entering the engine, including in the event of a leak in the intake system. The cast iron liners of the modernized engines are now extended to the upper plane of the cylinder block connector, which ensures the tightness of the combustion chamber for the engine life declared by the plant (250 thousand km). For engines produced before the end of 2007, the upper edge of the liner was below the plane of the connector of the cylinder block and cylinder head. This technical solution was dictated by plane processing technology - a cutting tool works better on homogeneous material. However, operation revealed that gases penetrated the joint between the liner and the block, which affected the reliability of the engines. Bringing the liner to the level of the connector significantly increased the tightness of the cylinder head seal, which made it possible to use liquefied gas as fuel. Among the significant modernization steps, I would like to note the use of piston rings from the Czech company Buzuluk and the application of sealant from Hehkel to the gaskets. In order to reduce oil consumption, improve the operating conditions of the piston rings and thereby increase the service life of the cylinder-piston group, instead of traditional honing with a diamond stone, the plant uses the so-called soft treatment of the liner surface, in which significantly less pressure is applied to the honing stones. To adapt the operation of the engine on gas fuel, changes were made to the geometry of the pistons, the gaps in the valve-bushing interface were reduced, and the piston pins were made using the cold extrusion method. The connecting rod and main journals of the crankshaft are hardened on the German automatic line “AEG-Elotherm”. To reduce the likelihood of gas loosening in cylinder block castings, a degassing unit for aluminum alloys from the German company Foseko was installed and launched.

STEIR - ALPINE LEGEND

Even the very first owners of a Nizhny Novgorod semi-truck dreamed of an economical and reliable diesel engine for it. But it still doesn’t exist, although the production of licensed Steyr diesel engines has been mastered in Nizhny since 1995, immediately renaming it GAZ-560. But to this day it is a rare engine, unfamiliar to carriers. However, there is a place in Russia where everyone knows about him. Two years ago, in St. Petersburg's Third Park, about 800 Gazelles were powered by these diesel engines. Agree, this is an excellent statistical sample; you can make a reliable list of typical breakdowns, despite the fact that local engineers and repairmen have something to compare with. On the same routes with these Gazelles, cars with gasoline engines, and even IVECO diesel engines, and, in addition, diesel Ford Transit and Mercedes Vario, operate.

Diesel GAZ-560: experience, son of difficult mistakes

The main feature of the Steyr M1 engine is the cylinder block, combined with the head into a monoblock. The block and head are one casting, without mounting pins or bolts, without any connector and therefore without a cylinder head gasket. From below, the main bearing housing of the crankshaft (full-support shaft) is secured to the monoblock with ten M12 bolts (it would seem that the bolts on a diesel engine should be thicker), and the same bolts also attract the main caps. A camshaft housing is installed on top of the monoblock, and the timing drive is by a toothed belt. So it’s impossible to make a motor completely without connectors.

The monoblock design, in comparison with engines with a removable head, has two advantages. The first is higher rigidity with the same material consumption. Rigidity is needed to maintain the correct geometry of the cylinder liners. Consequently, the engine turns out to be lighter, although with a volume of 2–2.5 liters the difference will be small, about 10–15 kilograms. The second advantage is the absence of a head gasket, which sometimes burns out on diesel engines. Either water goes into the cylinders, or oil gets into the antifreeze, but the result is the same - the gasket needs to be changed. However, usually this work can be successfully completed in 4–6 hours, maybe a little longer, by a more or less qualified driver or motor mechanic of the 3rd category. There were many more shortcomings. The combination of a clever Austrian design with Russian operating features created a rare explosive mixture.

The monoblock was known at the beginning of the twentieth century (remember the AMO F-15, with which the ZiL began), but the engines then were of large volume and low-power, there was no need to make developed channels for the jacket; it was made with reliable gears, and not with a toothed belt, like in Steyr M1. Often it is with the replacement of the belt that problems begin for an Austrian engine. The factory-equipped belts are quite durable, and the frequency of their replacement, according to GAZ instructions, is 120 thousand kilometers. But in the Third Park, belts are changed preventively at 90 thousand. And still, two or three cars a day are dragged on ropes with broken belts. One of the reasons is that there are no replacement belts of the required quality and reliability. Steyr is fitted with imported belts from two companies, and in both of them the frame breaks in half and does not cut off the teeth at all, as expected. One of these belts is thicker, it runs better, but it is difficult to stretch onto the camshaft toothed pulley, and with its back side onto the water pump pulley. It happens that the thread is pulled out from the aluminum camshaft housing, on which the timing belt tension roller pin is screwed in, then the belt slips several teeth. There is only an M10 thread, for restoration they cut M12, it holds more reliably.

OPINION

Igor Sibirev chief engineer of JSC "Third Park", St. Petersburg - When using a licensed Steyr M1 diesel engine on a Gazelle, the money saved on fuel is unlikely to be enough for its expensive repairs.

Foreign cars don't break down?

It is known that diesel engines from various manufacturers provide some protection that reduces engine damage when the belt breaks. In Volkswagen, when the valves and piston “meet”, the camshaft bursts into several pieces, but this is still cheaper than changing the head. The cast iron 2.5 liter Ford Transit engines, produced for almost 20 years, until the beginning of the third millennium, only had rods that bent. It was a very good decision - I leveled them with a hammer, put them in place, adjusted the valves, and you can continue driving. With Steyr, when the belt breaks, at best, the single-arm valve levers - rockers - burst in half. Each costs about 700 rubles, and there are eight of them, so in total you will only have to spend 5,600 rubles on them. It happens that not all rockers break, but if they fly apart on the fourth cylinder, you have to remove the camshaft housing; on the other three cylinders you can do without this for replacement. Accordingly, different labor intensity results. If without removing the camshaft, then an experienced repairman can fix the breakdown in 1.5–2 hours, otherwise it will take twice as long. It doesn’t seem like a very terrible defect, but crumbs from broken rockers get into the pan, and from there through a large oil receiver mesh into the oil pump. What gets ground there can also get to the crankshaft liners and tear them. What kind of resource is there after that? It happens even worse when the belt breaks at crankshaft speeds above average. Then the valves bend, and to get to them, you have to remove the engine and completely disassemble it, disrupting the running-in of many parts. Such a breakdown can put a car with only 100 thousand kilometers on the road for several days or a couple of weeks. And it’s not just the complexity of the repair; one of the reasons for the delay is the lack of spare parts. As in the old days of general shortages, they are allocated to Steyr according to a quota, and if it is selected, you will have to look for other suppliers, and the price can increase by one and a half to two times.

In general, it is the monoblock that causes the main problems. On average, a Steyr takes 200–300 thousand kilometers on a minibus before it is overhauled, and if you’re lucky, a little more. For comparison, diesel engines in the heavier Ford Transit run at least twice as good; in the same “Third Park” there is a car that has worked for more than a million without capital. Perhaps Steyr will last longer on a Volga with one owner, but that’s exactly how it works on a Gazelle.