Any engine internal combustion lubrication of rubbing parts is necessary, and engines of the ZMZ family are no exception in this regard. Without constant lubrication, such an engine will work for a maximum of an hour, after which it will simply jam. Its cylinders and valves will be seriously damaged, and it will be extremely difficult to repair such damage. Therefore, the oil pressure in the ZMZ engine is the most important indicator that the car owner must carefully monitor. But on domestic cars with ZMZ motors, oil pressure very often disappears. Let's try to figure out for what reasons this happens and how it can be eliminated.
About ZMZ engines
Before talking about oil pressure, it is worth introducing the reader to the engine itself. ZMZ engines are produced by the Zavolzhsky Motor Plant. They have 4 cylinders and 16 valves.
ZMZ engines are produced by the Zavolzhsky Motor Plant
These motors are installed on Volga, UAZ, GAZelle, Sobol cars. The family includes motors ZMZ-402, 405, 406, 409, 515 and a number of their special modifications. ZMZ engines have their advantages:
- good maintainability;
- simplicity of the device;
- low demands on the quality of fuel.
But there are also disadvantages:
- the timing drive is very cumbersome;
- the reliability of the chain tensioner in the timing drive leaves much to be desired;
- piston rings have an archaic design. As a result, large lubricant losses and power drops are observed;
- the overall quality of casting and heat treatment of individual engine parts is getting worse every year.
Oil pressure rate in ZMZ engines
The pressure in the lubrication system is measured only on a well-heated engine running on Idling... The crankshaft rotation speed at the time of measurement should not exceed 900 rpm. Here are the ideal oil pressure rates:
- for motors ZMZ 406 and 409, a pressure of 1 kgf / cm² is considered ideal;
- for motors ZMZ 402, 405 and 515, the ideal pressure is 0.8 kgf / cm².
It should be noted here that the highest pressure in the lubrication system of the ZMZ engine can theoretically reach 6.2 kgf / cm², but in practice this almost never happens. As soon as the oil pressure reaches 5 kgf / cm², the pressure reducing valve in the motor opens and the excess oil goes back to the oil pump. So the oil can reach the critical level only in one case: if the pressure reducing valve is stuck in the closed position, and this happens extremely rarely.
Checking the oil pressure
Oil pressure is displayed on dashboard car. The problem is that it is far from always possible to trust these numbers, since the devices can also fail and begin to give incorrect readings. It often happens that the oil pressure is normal, but the instruments show that there is no pressure at all. For this reason, it is advisable to simply inspect the vehicle. Here's how to do it:
If all of the above measures did not work, and the reason low pressure not identified, the last way remains: use an additional pressure gauge.
Signs of a drop in oil pressure
If the oil pressure in the engine drops sharply, it is impossible not to notice it. Here are the main signs that something is wrong with the engine lubrication system:
- the motor began to overheat quickly. At the same time, the exhaust gas becomes larger, and the exhaust has a black color, which is especially noticeable when the car picks up speed;
- bearings and other parts subject to intense friction began to wear out very quickly;
- the engine began to pound and vibrate. The explanation is simple: there is little lubrication in the motor, the rubbing parts gradually wear out and the gaps between them increase. In the end, the details become loose, begin to knock and vibrate;
- the smell of burning in the cabin. If the oil pressure is lowered, it begins to oxidize at a faster rate and burns out. And the driver smells the combustion products.
Reasons for lowering oil pressure and their elimination
First of all, it should be noted that a drop in oil pressure is a malfunction, which is a common "disease" of all engines of the ZMZ family, regardless of their model. There are no special nuances associated with this malfunction and characteristic of any particular engine from the ZMZ family. For this reason, below we will consider the reasons for the drop in oil pressure in the ZMZ-409 engine, which is currently the most popular in our country. Here it should be said that the most common reason for a drop in oil pressure is an incorrect viscosity coefficient, aka SAE. Due to this driver error engine oil may become too liquid in hot weather. Or vice versa, in severe frost, it can quickly thicken. Therefore, before looking for a problem in the engine, the car owner should ask himself a simple question: did I fill in the oil?
A sharp drop in engine oil
If the oil pressure in the ZMZ engine drops sharply, then this can happen for two reasons:
It should be noted here that the above breakdowns are quite rare. For this to happen, the driver must absolutely "start" the engine and not change the oil in it for years, or use a lubricant that is not suitable in terms of viscosity for a long time.
Gradual drop in oil pressure
This problem is very common in all engines of the ZMZ family, without exception. It can arise due to many factors: these are design errors, which were mentioned above, and improper maintenance, and natural wear of parts, and much more. Here are the most common causes of a gradual drop in oil pressure:
- wear oil filter... Gazelle drivers strongly recommend changing these filters every 5-6 thousand km, and changing the oil every 10 thousand km. If this is not done, a dirty sludge forms in the oil, no matter how good it is, which gradually clogs the oil filter. And the driver at this moment observes the above signs of a drop in oil pressure;
Oil filters on motors ZMZ should be changed as often as possible
- general engine wear. First of all, this applies to the intermediate shaft, on which the main pressure losses take place. This is due to wear on the shaft support sleeves. The hydraulic chain tensioner can also wear out, which also does not differ in durability. In addition, the cylinder head itself and the camshafts are often worn out. At the slightest wear in this system, the pressure begins to drop, and the oil consumption gradually increases. A worn-out oil pump, which is simply not able to supply a sufficient amount of lubricant to the motor, can also cause a pressure drop. And finally, hydraulic lifters on the valves can fail, which also reduces the lubricant pressure. There is only one solution to all of the above problems: engine overhaul;
- wear of the pressure reducing valve. The pressure reducing valve has a spring that can weaken over time. As a result, part of the oil goes back to the oil pump, which leads to a decrease in oil pressure. Some motorists solve the problem simply: they put a couple of small washers under the spring in the valve. But this, as you might guess, is only a temporary measure. And the only correct solution is to replace the pressure reducing valve with a new one (it will not work to purchase a new spring for the valve - they are not sold separately);
The spring is the main component of the pressure reducing valve in the ZMZ motor
- oil cooler leak. Radiators, in which the oil is cooled, are on many cars with ZMZ engines. However, these radiators are used extremely rarely, as their quality leaves much to be desired. Of particular note is the oil cooler tap. This tap is constantly leaking. Solution: refuse to use an oil cooler, because when correct selection oil, the need for this device simply disappears. Or the second option: put a high-quality valve on the radiator (preferably a ball valve, made in Germany, but by no means Chinese).
Video: looking for the cause of the drop in oil pressure in the ZMZ engine
So, there are many reasons causing a drop in oil pressure in engines of the ZMZ family. Some of them are the result of "congenital diseases" of this motor. Others are the result of the driver's own carelessness, and still others are the result of banal mechanical wear and tear. Most of these problems can be eliminated on their own, but the overhaul of the motor will have to be entrusted to a qualified specialist.
To all good day... In today's article we are considering a typical problem - the oil pressure in the ZMZ 406 engine has disappeared. Unfortunately, this is a fairly common problem and there are quite a few typical reasons in the article, we will analyze all the reasons and how they manifest themselves.
Let's start with a description of the design of the ZMZ 406 lubrication system:
The oil pump is driven from the intermediate shaft through a hexagon. The oil pump has a pressure reducing valve that relieves excess oil pressure back into the crankcase. From the oil pump, oil is fed through a filter to the main oil line, from which the journals are lubricated crankshaft, and bushings of the intermediate shaft of the timing drive. Also from the main highway there is a channel to the cylinder head and to the hydraulic tensioners. In the cylinder head, 2 oil channels are drilled parallel to the camshafts. These channels supply oil to each camshaft journal and to each of the 16 hydraulic lifters.
Most problem areas in the lubrication system - a pressure reducing valve, intermediate shaft bushings and hydraulic chain tensioners, but first things first ...
The oil pressure in the ZMZ 406 suddenly disappeared.
There are only two reasons in this case - the oil pump pressure relief valve is stuck in the open position. It looks like this:
This happens, usually, due to the ingress of dirt under the pressure reducing valve. Even the smallest crumb wedges the valve and it does not close completely.
The second typical reason is a breakdown of the oil pump drive.
The drive looks like this:
It should be noted that these two malfunctions are extremely rare and occur when the oil change interval is not observed and when operating on oil that does not correspond to the climate.
The oil pressure in the engine dropped gradually.
This is the most typical problem, it is associated with normal wear and tear, periodicity of maintenance and design errors.….
The most common reason is the oil filter.
During the operation of the gazelle (2705), I changed the filter every 5000 km, and changed the oil every 10,000 km. The reason is that when operating on gasoline, the oil quickly darkens and a heap of dirt forms in it that clogs the filter. When operating on gas, this problem is not observed!
The second most popular reason is the ingress of gasoline into the fuel.
Basically, the share of carburetor versions of the 406 engine is fair (when the gasoline pump membrane breaks, gasoline inevitably gets into the oil), but also on injection engine with a traveling nozzle, this is a perfectly possible scenario.
The third reason is wear and tear.
Due to wear, all the gaps in the friction pairs gradually increase.
- The main place where pressure is lost is the intermediate shaft. Many do not change the intermediate shaft support bushings even when overhaul but it is in these bushings that most of the pressure is lost.
- The second most popular place is the worn out hydraulic chain tensioners.
- The third place is cylinder head wear and camshaft wear .. The fact is that on the 406 engine, the camshaft beds are located in the cylinder head body and at the slightest "drift" of the plane, the bed wear increases significantly - the result is a pressure loss. With the wear of the shaft itself, the clearance in the friction pair increases and pressure is also lost.
- The fourth place is the wear of the oil pump. When worn, the pump will not pump enough oil into the engine lubrication system and there will be no oil pressure. You can deal with this by rebuilding the pump with the output of its planes or replacing the oil pump assembly with an oil pump from ZMZ 514 (it is for a diesel engine and has increased performance).
- Fifth place - hydraulic compensators for valve clearances, expansion joints in the cylinder head 16 (according to the number of valves) and at high mileage their beds are also subject to wear and tear, but the service life of the expansion joint beds, as a rule, exceeds the service life of the cylinder head.
The fourth reason is the oil bypass valve springs.
A bypass valve is installed on the oil pump housing, it opens when high pressure oils. The fact is that over time, the valve springs weaken and some of the oil pressure is lost on this valve. It's okay if you place a couple of washers under the valve spring when overhauling the pump.
About the oil cooler.
On some modifications of the ZMZ 406, a radiator is installed for cooling the oil, but in fact this design is practically not used since it reduces the pressure of the already liquefied oil and has low-quality taps that are constantly running. Relatively competently, the oil cooler is implemented at ZMZ 405 (a thermal valve is used), but even there its effectiveness is questionable. In most cases, it is advisable to muffle the oil cooler and use a more thermostable oil (tested on personal experience with gas 2705 with a mileage of 470,000 km).
Ways to increase the oil pressure in the ZMZ 406 engine during operation.
- More frequent replacement oil filter.
- Replacing the oil pump with a pump from ZMZ 514, part number 514 .1011010
- Disconnecting the oil cooler or replacing it with a heat exchanger.
- Replacing the oil with a thicker and higher quality one, it is the viscosity at high temperatures that is important.
- Placing 2-3 washers under the oil bypass valve spring
Ways to increase oil pressure during overhaul.
Be sure to reverse the countershaft and turn the bushings correctly.
Install the jets in the lubrication system.
The fact is that there are several places in the engine where a lot of pressure is lost, and in order to increase the life of the engine during a major overhaul, it makes sense to plug some channels in the lubrication system with carburetor jets! The best option turned out to be jets reamed with a 2 mm drill.
So, here are these places and options for their jetting:
Oil pump shaft lubrication hole
Hydraulic chain tensioners (top and bottom)
That's all for me. I hope that the problem of missing oil pressure in the 406 engine will never bother you again.
Control over the operation of the lubrication system in ZMZ 405, 406 and 409 engines is carried out using special oil pressure sensors. If they fail, the driver will not be able to respond in a timely manner to possible malfunctions in the system, which will jeopardize the further performance of the entire power unit.
Pressure and emergency pressure sensors for engine oil ZMZ 405, 406, 409
In order to monitor the pressure in the lubrication system of ZMZ 405, 406 and 409 engines, two separate sensors are provided. One of them fixes the magnitude of the pressure, and the second reacts to its critical drop.
Characteristics, design and principle of operation of the oil pressure sensor
The oil pressure sensor (DDM) is used to measure the lubricant pressure in the system. V power plants ZMZ uses sensors of the MM358 type with the following characteristics:
- working element - rheostat;
- rated current, A - 0.15;
- working range, kgf / cm 2 - 0–6;
- resistance in the absence of pressure, Ohm - 159-173;
The design of the MM358 pressure sensor consists of:
- housings with a union;
- membranes;
- pusher
- rheostat;
- elements of the rheostat drive.
The MM358 sensor works in conjunction with a pressure indicator located on the vehicle dashboard. It has an electromechanical design that responds to changes in the resistance of the sensor.
The principle of operation of the MM358 sensor is as follows: when the engine is not running, there is no pressure in the lubrication system. The resistance of the sensor, in accordance with its characteristics, is 159–173 Ohm. When the power unit is started, the pressure increases, and the oil begins to act on the membrane, bending it into the body. Bending, it moves the transmission lever through the pusher, which, in turn, moves the sliders of the rheostat to the right, reducing the resistance of the sensor. The pointer reacts to this decrease by moving the arrow to the right.
Characteristics, design and principle of operation of the emergency oil pressure sensor
The emergency sensor is designed to inform the driver about the drop in oil pressure in the system to critical values. V power units ZMZ 405, 406 and 409 are installed emergency oil pressure sensors type MM111D or similar, produced under catalog numbers 2602.3829, 4021.3829, 6012.3829. These are contact-type devices, the principle of operation of which is based on the closing and opening of contacts.
Characteristics of the MM111D sensor:
- working element - diaphragm;
- rated voltage, V - 12;
- actuation at pressure, kgf / cm 2 - 0.4–0.8;
- the size of the landing thread, in inches - ¼.
A spring-loaded diaphragm is located inside the body of the device. A contact plate is attached to it, which, when inoperative, is closed with the body (ground) of the sensor. During engine operation, lubricant under pressure enters through a special hole in the housing and pushes the diaphragm. In this case, the contacts open.
The emergency pressure sensor works in tandem with an indicator located on the instrument panel. It is designed in the form of a red oil can. When we turn on the ignition without starting the engine, the oiler should be on. This indicates that voltage is applied to the sensor and there is no pressure in the system. In 3-5 seconds after starting the engine, the pressure in the system increases and reaches the operating parameters. The oil acts on the diaphragm, the contacts open, and the signaling device goes out.
Where are pressure sensors manufactured?
Pressure sensors for ZMZ engines are produced both at the Ulyanovsk Automobile Plant and at other enterprises specializing in the manufacture of auto parts:
- Avtopribor;
- "Pekar";
- "EMP" and others.
Location in power units ZMZ 405, 406, 409
In ZMZ motors, the location of both sensors is identical. You will find them on the top left of the cylinder head (as viewed from the passenger compartment) above the exhaust manifold. And if the emergency sensor may not be immediately visible, then the oil pressure sensor is identified instantly by the barrel-shaped body.
Both sensors are screwed into one bifurcated fitting (tee), which is screwed into the cylinder head and connected to one of the oil channels of the lubrication system. Power wires are connected to the sensors.
How to check the oil pressure sensor
If you have any suspicions about the performance of the pressure sensor, do not be too lazy to check it. You can do it like at the station Maintenance, and at home. But in the latter case, you will need to purchase a special pressure gauge. It costs about 300 rubles, but such a thing will be useful in the future. In addition to him, you will also need a slotted screwdriver, a 22 key and electrical tape.
Checking procedure:
Video: checking the oil pressure in the system
Other malfunctions
However, the deviation in the value of pressure can be associated with wiring faults, and with malfunctions of the gauge itself. Do not be lazy to carry out additional diagnostics. Its order is as follows.
We turn on the ignition. The pointer arrow should deviate to the right, and then return to its original position. If the arrow does not deviate, use a slotted screwdriver to unscrew the screw securing the sensor power cable, disconnect it and touch the ground. The arrow has deviated - there is a short circuit in the sensor power supply wiring. If not, the problem should be looked for in the pressure gauge.
Checking the emergency oil pressure sensor
To check the device you will need:
- slotted screwdriver;
- key for 22;
- ohmmeter (multimeter);
- tire pump with pressure gauge;
- a section of hose with clamps of the appropriate diameter.
Checking procedure:
How to independently make a replacement in ZMZ 405, 406, 409 motors
Instruments:
- slotted screwdriver;
- keys for 17 and 22;
- automotive sealant;
- dry cloth;
- marker.
Replacement procedure:
- Disconnect the ground wire from the battery.
- Using a slotted screwdriver, unscrew the screw holding the tip of the pressure sensor power cable. Disconnect the wire.
- If you decide to replace both sensors, use the same tool to unscrew the fastening of the emergency sensor power wire.
- In order not to confuse the wires, we mark them with a marker.
- Using a 17 key, unscrew the oil pressure sensor. We remove it to the side.
- Using a 22 key, unscrew the emergency oil pressure sensor.
- We carefully wipe the sensor seats, remove the remnants of the old sealant.
- Lubricate the sensor fittings with a thin layer of automotive sealant. Let it dry a little (30 s).
- We screw in new sensors using keys 17 and 22.
- We connect the power wires.
- We connect the mass to the battery.
- We check the operation of the sensors.
Video: replacing the oil pressure sensor on a Gazelle car
Whether you decide to diagnose and replace sensors yourself, or resort to the help of specialists, it doesn't matter. The main thing is to be sure that the lubrication system is operating normally and to have confirmation of this in the form of normal indicators of the corresponding devices, rather than rely on the fact that everything will work out.
Four-cylinder in-line engine, equipped with an integrated microprocessor
fuel injection and ignition control system (KMSUD).
Engine type mod. 4062 on the left side:
1 - drain plug;
2 - oil sump;
3 - exhaust manifold;
4 - engine support bracket;
5 - valve for draining the coolant;
6 - water pump;
7 - coolant overheat lamp sensor
liquids;
8 - the sensor of the gauge of temperature of the cooling
liquids;
9 - tempera sensor;
10 - thermostat;
11 - emergency lamp sensor
oil pressure;
12 - pressure gauge sensor
oils;
13 - crankcase ventilation hose;
14 - oil level indicator (dipstick);
15 - ignition coil;
16 - phase sensor;
17 - heat-insulating screen
The cylinder block is cast from gray iron. There are channels between the cylinders for
coolant. The cylinders are designed without insert sleeves. At the bottom of the block
there are five bearings of the crankshaft main bearings. Indigenous caps
The bearings are made of ductile iron and are attached to the block with two bolts. Lids
bearings are bored with the block, so they cannot be swapped.
On all covers, except for the third bearing cover, their serial numbers are stamped.
The cover of the third bearing together with the block is machined at the ends for installation
thrust bearing half washers. The chain cover is bolted to the ends of the block and
stuffing box with crankshaft cuffs. An oil sump is attached to the bottom of the block.
On top of the block is a cylinder head, cast from aluminum
alloy. It has intake and exhaust valves. For each cylinder
installed four valves, two inlet and two outlet. Inlet valves
located on the right side of the head, and the outlet on the left. Valve drive
is carried out by two camshafts through hydraulic tappets.
The use of hydraulic pushers eliminates the need to adjust the clearances in the drive
valves, as they automatically compensate for the gap between the cams
camshafts and valve stems. Outside on the body of the hydraulic pusher
there is a groove and a hole for supplying oil inside the hydraulic pusher from oil
highways.
Engine type mod. 4062 on the right side:
1 - synchronization disk;
2 - sensor of rotation frequency and synchronization;
3 - oil filter;
4 - starter;
5 - knock sensor;
6 - pipe for draining the coolant;
7 - air temperature sensor;
8 - inlet pipe;
9 - receiver;
10 - ignition coil;
11 - idle speed regulator;
12 - throttle;
13 - hydraulic chain tensioner;
14 - generator
The hydraulic pusher has a steel body, inside which a guide is welded
sleeve. An expansion joint with a piston is installed in the sleeve. The compensator is held in
sleeve with a retaining ring. An expansion joint is installed between the expansion joint and the piston.
spring. The piston rests against the bottom of the hydraulic pusher housing. Simultaneously
the spring presses the ball check valve body. When the cam
camshaft does not press on the hydraulic pusher, the spring presses through
the piston the body of the hydraulic pusher to the cylindrical part of the camshaft cam
shaft, and the compensator - to the valve stem, while choosing the clearances in the drive
valves. The ball valve is open in this position and oil flows into the
hydraulic pusher. As soon as the camshaft cam rotates and presses on
pusher body, the body will drop down and the ball valve will close. Butter,
located between the piston and the compensator begins to work as a solid.
The hydraulic tappet moves downward under the action of the camshaft cam and opens the valve.
When the cam, turning, stops pressing on the body of the hydraulic pusher, it is under
the action of the spring moves upward, opening the ball valve, and the entire cycle
repeats again.
Cross section of the engine mod. 4062
1 - oil sump;
2 - oil pump receiver;
3 - oil pump;
4 - oil pump drive;
5 - gear wheel of the intermediate shaft;
6 - cylinder block;
7 - inlet pipe;
8 - receiver;
9 - intake camshaft
valves;
10 - inlet valve;
11 - valve cover;
12 - exhaust camshaft
valves;
13 - oil level indicator;
14 - hydraulic valve pusher;
15 - external valve spring;
16 - valve guide sleeve;
17 - exhaust valve;
18 - cylinder head;
19 - exhaust manifold;
20 - piston;
21 - piston pin;
22 - connecting rod;
23 - crankshaft;
24 - connecting rod cover;
25 - main bearing cover;
26 - drain plug;
27 - pusher body;
28 - guide sleeve;
29 - compensator body;
30 - retaining ring;
31 - compensator piston;
32 - ball valve;
33 - ball valve spring;
34 - ball valve body;
35 - expanding spring
Seats and guide bushings are installed in the block head with a high interference
valves. Combustion chambers are made in the lower part of the block head, in the upper part -
the camshaft supports are located. The supports are equipped with aluminum
cover. The front cover is common to the inlet and outlet supports.
camshafts. This cover contains plastic stop
flanges that fit into the grooves on the camshaft journals. Lids
are bored together with the block head, so they cannot be swapped. On
all covers, except for the front one, have serial numbers stamped.
Camshaft cover installation diagram
The camshafts are cast iron. Intake and exhaust cam profiles
the shafts are the same. The cams are offset by 1.0 mm relative to the axis of the hydraulic pushers, which
makes them rotate when the engine is running. This reduces surface wear
hydraulic pusher and makes it uniform. The top of the block is closed with a lid on top,
cast from aluminum alloy. The pistons are also cast from an aluminum alloy. On
the bottom of the piston has four valve recesses, which prevent
strokes of the piston on the valves in case of a violation of the valve timing. For the correct
installation of the piston into the cylinder on the side wall at the boss under the piston pin is cast
inscription: "Before". The piston is installed in the cylinder so that this inscription is
facing the front of the engine.
Each piston has two compression rings and one oil scraper ring.
Compression rings are cast iron. Barrel-shaped work surface of the upper
the ring is covered with a layer of porous chromium, which improves the running-in of the ring. Working
the surface of the lower ring is coated with a layer of tin. On the inner surface of the bottom
the ring has a groove. The ring must be installed on the piston with this groove.
up to the bottom of the piston. Oil scraper ring consists of three elements: two
steel discs and expander. The piston is attached to the connecting rod using a piston
"floating type" finger, i. e. the pin is not secured in either the piston or the connecting rod. From
the movement of the pin is held by two snap rings, which
installed in the grooves of the piston bosses. Forged steel connecting rods, with a rod
I-section. A bronze bushing is pressed into the upper head of the connecting rod.
The lower connecting rod head with a cover that is fastened with two bolts. Connecting rod nuts
the bolts have a self-locking thread and therefore do not additionally lock.
The connecting rod caps are processed together with the connecting rod, and therefore they cannot
rearrange from one connecting rod to another. Numbers are stamped on connecting rods and connecting rod caps
cylinders. For cooling the piston crown with oil in the connecting rod and upper head
holes are made. The mass of pistons assembled with connecting rods must not differ
more than 10g for different cylinders. The lower head of the connecting rod is installed
thin-walled connecting rod bearings... The crankshaft is cast from ductile iron.
The shaft has eight counterweights. It is held against axial movement by persistent
half washers installed on the middle neck. To the rear end of the crankshaft
flywheel attached. A spacer sleeve and bearing are inserted into the flywheel bore
input shaft of the gearbox.
Cylinder numbers are stamped on the connecting rods and connecting rod caps. For cooling the bottom
the piston with oil in the rod of the connecting rod and the upper head are holes. Weight
pistons assembled with connecting rods should not differ by more than 10 g for different
cylinders. Thin-walled connecting rods are installed in the lower head of the connecting rod
liners. The crankshaft is cast from ductile iron. The shaft has eight
counterweights. It is kept from axial movement by persistent half washers,
installed on the middle neck. Attached to the rear end of the crankshaft
flywheel. A spacer sleeve and a primary bearing are inserted into the flywheel hole.
shaft of the gearbox.
The ZMZ-406 lubrication system consists of an oil level indicator, an oil pump with an oil receiver, oil channels, an oil filter, a pressure reducing valve, an oil cleaning filter, an oil sump, an oil filler cap, an oil cooler, a safety valve and a shut-off valve.
The lubrication system of the ZMZ-406 engine is combined: the main and connecting rod bearings of the crankshaft, piston pins, camshaft bearings, bearings of the intermediate shaft and the oil pump drive shaft, hydraulic pushers and helical gears are lubricated under pressure. Other parts are spray lubricated.
The oil pump is gear-type, single-section driven from the intermediate shaft by means of a pair of helical gears. An oil cooler and a full-flow filter are integrated into the lubrication system. The oil level indicator has marks: the highest level "P" and lower level"O". The oil level should be close to the "P" mark, not exceeding it.
Oil can be delivered to work surfaces under pressure, spray and gravity. The choice of the method of supplying oil to a particular part depends on the conditions of its operation and the convenience of supplying lubricant. V car engines a combined lubrication system is used, in which lubricant is supplied to the most loaded parts under pressure, and to the rest of the parts by spraying and gravity.
Oil path from pump to timing valve assembly
A gear-type oil pump is installed inside the oil sump and is attached to the cylinder block with two pins. The pump body is made of aluminum alloy, the pump cover is made of cast iron, the pump gears are made of cermet. The drive gear is pinned to the shaft, the driven gear rotates freely on the axis pressed into the pump housing.
A 0.3 mm thick cardboard sealing gasket provides the required clearance between the ends of the gears and the cover. An oil receiver with a grid is attached to the lid of an aluminum alloy cast. A pressure reducing valve is located in the pump housing. Oil from the pump through the channels in the cylinder block and the outer pipe on the left side of the block is supplied to the oil filter.
From the oil filter through channels in the block, oil is supplied to the crankshaft main bearings and camshaft bearings, from the crankshaft main bearings through channels in the crankshaft, oil is supplied to the connecting rod bearings, and from the camshaft bearings through channels to the cylinder head for lubricating the rocker arms and upper rod ends.
Pressure reducing valve plunger type is located in the oil pump housing and is adjusted at the factory by installing a calibration spring. The adjustment should not be changed during operation. The oil pressure is determined by a pointer, the sensor of which is screwed into the oil line of the cylinder block.
In addition, the system is equipped with an emergency oil pressure indicator, the sensor of which is screwed into the lower part of the oil filter housing. The emergency oil pressure indicator lights up at a pressure of 0.4 ... 0.8 kgf / cm 2.
The oil pump is driven from the camshaft by a pair of helical gears. The drive gear is steel, cast into the camshaft body, the driven gear is steel, nitrocarburized, fixed with a pin on the shaft rotating in a cast iron housing. On the upper end of the shaft, a bushing is put on and secured with a pin, which has a slot shifted by 1.5 mm to the side for driving the ignition distributor sensor. An intermediate hexagonal shaft is pivotally connected to the lower end of the shaft, the lower end of which enters the hexagonal hole of the oil pump shaft.
The shaft in the drive housing is lubricated with oil, which is sprayed by the moving parts of the motor. The splashed oil, flowing down the block walls, enters the slot - a trap at the lower end of the body shank and through the hole enters the shaft surface.
The shaft hole in the housing has a helical groove, due to which the oil is evenly distributed during the rotation of the shaft along its entire length. Excess oil from the upper cavity of the drive housing flows back into the crankcase through a channel in the housing. The drive gears are lubricated by a jet of oil flowing from a 2 mm hole in the cylinder block and connected to the fourth camshaft bearing, which has an annular groove.
Oil purification filter - full-flow, with a cardboard replaceable element, located on the left side of the engine. All the oil pumped into the system by the pump passes through the filter. The filter consists of a body, a cover, a center rod and a filter element.
In the upper part of the central rod there is a bypass valve, which, when the filter element is clogged, passes oil, bypassing it, into the oil line. The resistance of a clean filter element is 0.1 ... 0.2 kgf / cm2, the bypass valve starts to bypass oil when the resistance increases as a result of filter clogging up to 0.6 ... 0.7 kgf / cm2.
The oil cooler serves for additional cooling of the oil during the operation of the car in summer, as well as during prolonged driving at speeds above 100-110 km / h. The oil cooler is connected to the engine oil line by means of a rubber hose through a stopcock and a safety valve, which are installed on the left side of the engine.
The position of the tap handle along the hose corresponds to the open position of the tap, across - to the closed one.
The safety valve opens the passage of oil to the radiator at a pressure above 0.7 ... 0.9 kgf / cm 2. The oil from the radiator is drained through a hose through the timing gear cover (on the right side of the engine) into the crankcase.
The crankcase ventilation is closed, forced, acting as a result of a vacuum in the intake manifold and in the air filter. When the engine is idling and at partial loads, gases from the crankcase are sucked into the intake pipe, at full loads - into air filter and an inlet pipe.
Lubrication diagram in cross-section of the engine
Figure 7 - Cross section of the ZMZ 406 engine (lubrication diagram)
1 - oil pump; 2 - oil sump; 3 - oil pump bypass valve;
4 - thermal valve; 5 - central oil line; 6 - oil filter;
7, 8, 10, 11, 12, 14, 17, 18, 19 - oil supply channels; 9 - fitting of the thermal valve to drain the oil into the radiator; 13 - cover of the oil filler pipe; 15 - handle of the oil level indicator;
16 - oil pressure alarm sensor; 20 - crankshaft;
21 - rod oil level indicator; 22 - hole for connecting the fitting of the hose for supplying oil from the radiator; 23 - oil drain plug
