Engine overhaul VAZ 2109 carburetor

The power unit is the most durable part of a car when used correctly. But even it requires major repairs after a certain period of time. The timing of the overhaul depends on the timeliness of the technical inspection and ongoing repair work. With proper engine care, major repairs of the VAZ 2109 engine can be avoided until the odometer reaches 150,000 km. If you use the power unit irrationally, repairs may be required much earlier.

Overhaul of the VAZ 2109 (KR) engine involves disassembling the engine into parts, carrying out diagnostics, repairs, and, if necessary, replacing individual components and assemblies. Typically, engine components are repaired by metalworking the elements, then the crankshaft is ground, the cylinder head is milled, and the engine block is cleaned and processed. If you are the owner of an imported car, it is better to entrust this procedure to professionals - service station employees. And Lada Samara drivers can easily repair a VAZ 2109 engine with their own hands, knowing the technology and the sequence of work.

Factors for the need for CR

To identify the need for a major overhaul of the Nine, you need to monitor the “symptoms” of your specific car. There are cases when, to eliminate a malfunction, it is enough to make do with scheduled repairs or spot replacement of components. But in some situations, such “refreshing” is not enough, and a faulty unit requires a radical restoration.

It is a mistake to believe that the most important criterion by which the overhaul period of the Lada 2109 is determined is mileage. This is not entirely true. If the driver carefully operates the engine, carries out timely maintenance, replaces the oil filter, oil, and coolant, then even when the indicator reaches 100–150 thousand km on the instrument panel, the car is not in danger of major repairs. And it happens the other way around. With a relatively low mileage, but irrational use of the engine, diagnostics show the need to completely repair the power unit.

The mileage goes on, and the need for major repairs is indicated by specific signs:

• oil consumption increases;
• compression (compression) in the cylinders decreases;
• fuel costs increase;
• There is a knocking sound in the VAZ 2109 engine.

An increase in oil consumption in the absence of leaks indicates wear of the piston rings and the inevitability of major repairs. If the engine is breathing, that is, oil leaks occur, you can get by with scheduled repairs. The frequency of replacement is also affected by the condition of the guide bushings and oil seals.

The second factor is the deterioration of the crank mechanism (crank mechanism). The quality of performance of the functions of the crankshaft is indicated by the compression value (maximum pressure in the combustion chamber at the greatest compression of the piston). This indicator can be measured using a pressure gauge, which is fixed in place of the pressure sensor. In this case, the engine must be running. We compare the obtained values ​​with the passport compression indicators (for the VAZ 2109 it should be in the range of 9.5–13 atmospheres). If the measured value does not reach the norm, there is severe wear of the bearings or hydraulic pump.

You cannot ignore such signs as a decrease in the stability of the internal combustion engine, the appearance of characteristic sounds (tapping, tinkling) at idle speed, an increase in gasoline consumption and a decrease in traction. There are times when the engine smokes. If one of these symptoms appears, you can do without major repairs, but if the problems appear in a complex and the engine does not pull, then, most likely, diagnostics will show the need for extensive engine repairs.

If the unit is running to the point of emergency, the VAZ 2109 engine may need to be replaced.

Do-it-yourself VAZ 2109 engine overhaul video

During operation, the power plant of your car will wear out more and more. At a certain point in time, there will be a need for major repairs (CR). If all the necessary maintenance and routine repair work was carried out regularly, then the engine will easily operate for up to 100,000 - 150,000 km without a major overhaul. Otherwise, the mileage to the Kyrgyz Republic will be significantly reduced. Contents:
The technology for overhauling a power plant includes complete disassembly of the engine, diagnostics of its individual components, repair or replacement of parts and assemblies. Repair work often involves metalworking of certain components, for example, grinding the crankshaft, milling the cylinder head, or honing the engine block. The service will charge a truly draconian fee for this. And if your car is a foreign car, then it is better to contact a service station. Owners of domestic cars can do everything themselves, and in this article we will tell you how to overhaul a VAZ 2109 engine yourself.

Overhaul of VAZ 2109, 2108 engine

To begin with, it is very important to determine whether the engine of your car needs CR. This applies to absolutely any power plant – both foreign and domestic. Perhaps it is enough to change or repair just a few components, and the engine will start working normally again. Let's look at the factors that indicate the need for an engine overhaul.

The widely held belief that high mileage on a car is directly related to major repairs is not entirely true. Indeed, if maintenance was carried out regularly, filters, oil, coolant, etc. were replaced. - then a six-digit figure on the odometer may indicate that it’s time to “shake up” the engine, but not always. If diagnostics show that all systems are working normally, why do anything? Now let's consider another situation. The owner of the car is irresponsible in its maintenance. Maintenance is not carried out, the car is operated in a suboptimal mode (for example, it takes part in racing events, although it is not prepared for them). Obviously, in this case the engine will have to be overhauled very quickly.

When to overhaul an engine

Now let's look at the signs that may really indicate the need for major repairs.

Since the crank mechanism (CCM) is one of the most important parts of the engine, if you suspect an urgent need for a crank mechanism, check its condition. This can be done by measuring the compression in the cylinders. Simply remove the pressure sensor and insert a pressure gauge in its place (of course, the motor must be running during this procedure). Then compare the measurement results with standard indicators. Is the compression insufficient? The bearings or hydraulic pump are probably very worn.

Please note if the engine suddenly becomes unstable, makes strange sounds in the form of tapping or jingling (especially at idle), consumes a lot of fuel, or stops developing full power. Separately, these signs indicate problems in individual components and assemblies, but if 2-3 of them appear at once, this most likely indicates the need for a major overhaul of the engine. To be completely sure of this, carry out diagnostics, maybe you just need to change some part(s) or tune the engine. No result? Well, we need to do a major overhaul.

During the overhaul, take the opportunity to check how worn out all the attachments are - generator, injector, fuel pump, thermostat, etc. If necessary, repair them or replace them with new units.

After completing a major overhaul, the engine should work like new and trouble-free service for another 100,000 - 150,000 km . mileage, subject to regular maintenance.

Before you start working on the power unit, outline your plan of action. First of all, sort out which procedures you will do yourself and which you will leave to the specialists. Then decide on the place where you will carry out the repairs. The ideal option is in your own garage with a pit. If you don’t have one, rent a suitable space or ask for help from friends who have such a garage. Also get a manual hoist with a chain drive and several slings for securing loads (with their help you will remove the engine block). You will also need something to place the block on, for example, a pallet or a tire of a suitable size.

Only now can you remove the engine and disassemble it into individual parts. It’s better not to buy spare parts right away - go to a car store as you go. Also, do not rush into machine work - upon closer examination, some parts, for example, the crankshaft, would be better replaced with a new one or a restored one. It is likely that the condition of the engine as a whole will be very poor, and then it would be more logical to buy a 2nd complete engine (i.e. it is a cylinder block and cylinder head assembly, but there are no attachments) entirely. Also, do not forget that major repairs will require serious cash injections from you and a lot of free time, so plan it in advance so that you don’t have to assemble the engine in the evenings after work.

How to assemble an engine for a VAZ 2109

So, first drain the operating fluids, remove attachments, tanks, radiator, etc. Then disconnect the engine and gearbox, and then pull out the unit using slings and a hoist, placing it on a tire or pallet. Next, remove the cylinder head and crankshaft. Don’t forget to mark where which bearing shells and caps were located, this will be very useful to you later. That's all, now you can start repairing and replacing parts, and then assembly. Perform these procedures in the following sequence:

That's all, the flywheel is installed, let's move on.

Self-repair of the cylinder head on a VAZ 2109

Let's start repairing the engine head. In the case of the cylinder head in the photographs, its inspection revealed that it had been milled, and not of very high quality. As a result, characteristic marks remained on the surface of the part, through which antifreeze seeped into the oil channel and then flowed into the crankcase.

As a result, the oil quickly lost its properties. This defect can be solved by grinding. After this procedure, the surface has become perfectly smooth, and antifreeze will no longer get into the oil.

Now it’s time to find out how to disassemble the cylinder head of a VAZ 2109. First, remove the rocker along with the springs.

Carefully inspect the rocker pressure plane. In the photograph, the red arrow marks a plane that gradually becomes rounded as it wears. If the rocker is positioned askew, this indicates the need to adjust the gap between it and the timing shaft. Was the rocker tilted relative to the shaft? This means that it is worn out, and therefore if you are planning to replace the valves with new ones, do the same with the rockers.

Next, we dismantle the valves and other parts. After the shaft is removed, remove the pushers along with the adjusting washers.

Then look into the wells where the pushers move. When the valve guide bushing is severely worn out, and the machine continues to be operated with these worn-out parts, the pushers develop a certain amount of play, as a result of which the wells turn from round to oval. This is clearly visible from the risks indicated by the red arrows in the photo. In this case, it is useless to install new guides - they will quickly fail. Such a defect is difficult to repair and often leads to the purchase of a new cylinder head, but in this case it was possible to correct it by processing on a boring machine followed by pressing in a bronze bushing.

General overhaul technology

A major overhaul of the VAZ 2109 internal combustion engine is used to completely restore the nameplate technical characteristics of the power unit. The main stages of repair work are as follows.

1. Replacing piston rings.
2. Grooving of cylindrical rings.
3. Cleaning and processing of the crankshaft.
4. Replacing bearings.
5. Cylinder head repair.

During the repair process, the piston rings are replaced, and the cylinder rings are ground and finished. This must be done using turning equipment, so it is better to entrust this procedure to specialists. Due to the bore of the cylinders, it is necessary to replace the pistons with new ones; To replace the piston, special mandrels are needed.

The crankshaft often requires a good cleaning and treatment. Due to its structure, this element is susceptible to clogging with dirt and debris. When the lubrication hole is clogged, the crankshaft journals do not receive enough lubrication, which leads to a decrease in crankshaft efficiency.

It is necessary to replace the main and connecting rod bearings, because their wear causes Lada engine malfunctions. A very important step is repairing the cylinder head. Support plates, valves, and return springs are repaired (replaced).

When carrying out a major overhaul of an internal combustion engine, do not forget about the accompanying devices: generator, injector, fuel pump, thermostat. If malfunctions are also detected in their operation, the unit should be repaired or replaced.

Before you start working on the engine, you should decide what procedures you will perform yourself (disassemble, sort through, clean, process). It is better to entrust cylinder boring to a specialist. The quality of the repair also depends on the location where it is carried out.

It is most convenient to carry out the inspection in a garage with its own inspection hole.

Overhaul of VAZ 2109 engine

Source

Disassembly, repair and installation of the engine

To begin, drain the operating fluids and detach the attachments and auxiliary elements. Next you need to disconnect the unit from the gearbox. Now you can pull out the block using a hoist.

The piston group is replaced in most cases. If desired, it can be restored using special equipment, but this can be even more expensive. We insert the piston assembly with the connecting rod inside the cylinder. Then we place the connecting rod in the groove of the crankshaft journal, insert the liners, and lubricate all the parts. We mount the lower covers on the connecting rods (each connecting rod has its own cover).

We fix the oil pressure sensor and other auxiliary parts. This completes the installation of the VAZ 2109 engine.

The engine is overhauled in the following cases: destruction of the pistons due to a broken timing belt; natural wear of the piston group; compression loss in the cylinders.

Before starting work, you can think about tuning (improving) the engine. Whatever the car, it is possible to increase the number of horsepower, and without significant costs. Let's look at the main stages of repair work so that you have an idea of ​​what you will have to face.

Where to start and where to end

Repair work begins with dismantling the deformed, rotten parts of the “nine”:

1. Disassembling the engine compartment, draining coolant and antifreeze.
2. Removing the doors.
3. Dismantling the amplifier - “TV”.
4. Rusty areas are cut off with a grinder.
5. The holes will have to be repaired or patched.
6. Problem areas are strengthened with iron.
7. Mudguards are reinforced with spot welding.
8. Spare parts are adjusted in accordance with the geometry of the car.
9. Thresholds and wings are fastened with bolts followed by electric welding.
10. New arches are installed, and if necessary, the bottom is completely changed.

To prevent the occurrence of corrosion, vulnerable areas are coated with special compounds based on bitumen, resin, and oil. The surface is pre-polished, removing a layer of paint and varnish, increasing adhesion to the applied product.

Welding materials

When working with a welding machine, consumables are required. When choosing them, they are guided by two points:

1. Thin steel is more difficult to weld and requires proper selection of temperature conditions.
2. Thick ones are more difficult to process.

In the lessons, experts advise using metal 1–2 mm thick for patches. The car is inspected on an overpass or pit in good lighting. The strength of the metal is checked with a hammer, which is used to tap the damaged areas.

For further restoration work, you will need soundproofing materials, anti-corrosion compounds, a metal primer, a rust converter, and a degreaser.

Preparatory stage

If the bottom is severely damaged, it is more profitable to replace it than to install metal patches. Large defects are cut out during preparatory work, small ones are cleaned from corrosion. Hard-to-reach areas are treated with gas welding. The seams on patches and repair inserts are coated with a rust converter, cleaned, degreased, and coated with anti-corrosion compounds.

Welding process

The fuel tank must be dismantled before starting work. The patch on the damaged area is welded at 3-4 points, then scalded. For minor defects, small seams up to 3 cm are applied. There should be no gaps - they increase the risk of corrosion. To increase the strength of the seams, they are hammered. If necessary, all parts can be digested. Restored areas are cleaned after inspection.

Removing the engine from the car

This procedure cannot be avoided, since the motor must be removed, otherwise it simply cannot be completely disassembled. During the preparation stage, disconnect the battery to de-energize the power supply system. All attachments must be removed - carburetor, air filter, generator, starter, exhaust manifold, etc. Before dismantling the engine, you can also unscrew the cylinder head. Work with it will be carried out separately. Drain the oil from the crankcase, after which you will need a winch and assistants.

Four bolts secure the gearbox to the engine block. The engine and body on VAZ 2108-21099 cars are attached using one cushion. Suspend the engine on a cable and unscrew all the bolts, pre-treating the connections with penetrating lubricant to make work easier. For convenience, you can remove the hinges at the very beginning and move the hood to the side, this way you will have more space. After the final removal of the engine, you begin to disassemble it.

Now it’s worth talking about the requirements for each element of the motor.

Without removing the gearbox

In short, it is quite possible to remove the engine from your “nine” without removing the gearbox. To do this you will have to follow these steps:

• Place bricks or other reliable supports under the gearbox;
• Unscrew the left crab, move the stretcher aside;
• Remove the generator, crankshaft pulley, and camshaft gear from the engine;
• The pump, tensioner pin, distributor, and exhaust pipe are also dismantled;
• If a major overhaul is planned, then you can also remove the head;
• Then the engine mount is removed;
• The motor is moved from the box and lowered to the floor. To remove the engine, the front part is raised higher using a jack and the volume is removed;
• Or you can pull it out through the top using a winch.

In practice, all experts recommend dismantling the engine along with the gearbox. Especially if you plan to replace the engine or increase the power of the standard engine. In this situation, the box itself is often changed so that it can clearly interact with the new motor.

Gearbox from nine

Cylinder block

In any case, it needs to be repaired. First of all, clean the entire surface of oil, dirt and other deposits. The repair consists of boring the sleeves to the required size. You cannot carry out this procedure yourself; it is better to trust a specialist. The lathe who carries out the boring must have the skills to operate the machine. Do not trust such a task to an inexperienced person. Its reliability depends on how correctly the overhaul of the VAZ 2109 engine is done.

There are two boring options: under the mirror and with a fine mesh. In the second case, honing is done - the entire inner surface of the liners is covered with thin lines. Some people claim that this gives a boost in power. But in reality, the picture is the opposite - the wear of the piston rings increases, since the surface of the cylinder is similar to an ordinary file. Fortunately, this continues for 10-20 thousand km, after which the sleeve takes on a mirror-like appearance. Moreover, the geometry is not always ideal. For this reason, it is better to carry out boring under a mirror.

Is it worth lightening the pistons?

If you are interested in the idea of ​​tuning in order to increase power, then the answer is clear: it is necessary to lighten the pistons! But if it is in your interests only to make repairs, then it is enough to install new ones. In any case, the increase in horsepower will be noticeable, as engine compression will increase. It is best to entrust the work of lightening to the same turner who is engaged in boring the cylinder block. As you can see, you cannot do a major engine overhaul with your own hands; you will have to resort to the services of specialists.

Types of major repairs and cost differences

An engine is a complex mechanism in which any of the components can break. Major repairs may be required if the part breaks in several places. In pricing policy, the relationship is simple - the more damage, the more money you will have to pay. The complexity of the repair is often determined by the number of breakdowns and the general condition of the part.

If sand is already falling from the engine due to age, oil is leaking and the shaft is knocking, then you need to prepare for a serious financial blow. If something happens to the cylinders, even if nothing else is damaged, a major overhaul will still be needed.

Crankshaft and its relief

This is perhaps the most massive element of the entire engine. If you only need to carry out a major overhaul of the VAZ engine, then you can limit yourself to replacing the main and connecting rod bearings. But if you are looking to increase power, you will need to do a lot of work. Moreover, it will again be impossible to do without the services of a turner. After all, only by using professional equipment can you get rid of “excess” metal on the surface of the crankshaft.

But don’t forget about one feature. The crankshaft has an axis of rotation, its center of gravity is located in such a way that no beating occurs. When you grind off metal, the alignment is disrupted. And by installing such a crankshaft, you will simply destroy both the bearings and the cylinder block housing. Therefore, after lightening, it is necessary to do balancing in order to restore the alignment of the shaft. But after a major overhaul, the engine will be much more powerful, which will surprise you beyond words.

How, where and from whom can you order an engine overhaul?

Now even some auto repair shops have their own websites, where addresses, phone numbers and approximate prices are indicated. But you can always find them in search engines or online maps. At a minimum, so that the craftsmen can name the price tag and deadlines, they must see in front of them what needs to be repaired. Therefore, in any case, you need to bring the car to the service and take an interest in everything there.

Another question is that if there are problems with the engine, the services of a tow truck may be required, but they are not as expensive as it might seem at first glance. There are usually several services in any city, so finding one of them is not a problem.

Flywheel and clutch block

For tuning, these components should also be modified. As with the crankshaft, you will need to cut off a layer of metal from the inside of the flywheel. After this procedure, balancing is also necessary so that axial runout and, as a result, vibrations do not occur. You will need to use a reinforced clutch. Give preference to samples that are used for newer and more powerful car models. Based on what increase in horsepower you want to get in the end.

What is the service?

The engine is the key part of the car. Without it, it will not be able to perform its main function as a means of transportation. If the engine breaks down, there is a risk of losing control of the car on the road, so repair or replacement of this part should be carried out immediately when a malfunction is detected.

Carrying out a complete diagnosis and major repair is not so easy and it is not done everywhere. Especially when you consider that the car model is not the most common and certainly not a new product. Although there are skilled handicraftsmen who can carry out major repairs for a very modest fee, none of them can guarantee the quality. In addition, you will still have to pay extra for replacing engine components, so the savings in the end will not be so significant.

Oil pump and cooling system

Improving these components is extremely necessary when carrying out tuning. Lubrication of all units may be insufficient, as torque and power increase due to the lighter weight of the main elements. Carefully troubleshoot the oil pump gears so that the gaps are minimal. As for the cooling system, it would not be a bad idea to install a more efficient pump and a radiator with a larger area. A major overhaul of the 2109 engine, provided that there is no need to do tuning, can be done without these procedures.

Block head repair

This unit is responsible for the quality of sealing of the combustion chamber at the moment of ignition of the mixture. Therefore, you should achieve maximum contact between the valve surfaces and the seats in the cylinder head. To do this, it is necessary to carry out grinding. The work is not difficult, but tedious and long. You will need a drill with reverse (even a hand-held one will do), a piece of rubber hose, two clamps, a metal rod, lapping pastes - finishing and coarse. Please ensure that after carrying out the work there are no abrasives left on the surface of the cylinder head. Clean everything and blow it out with compressed air.

First, a rough lapping paste is applied to the seat. Using a drill, rotate the valve in different directions (it is highly desirable that there be an equal number of revolutions). After getting rid of large surface irregularities, you need to apply finishing paste and grind in until shiny. Maximum contact between valve and seat is now ensured. The main thing is to install them as they were ground in; elements cannot be swapped. In this case, it will be impossible to achieve maximum tightness.

Repair of VAZ 2109 car

The main component of the VAZ 2109 car, which requires periodic or major repairs, is the engine - the heart of the car. The reliability of transport operation depends on the condition of the unit. Therefore, do-it-yourself engine repair and maintenance for the VAZ 21099 will always be a pressing issue. To determine the type of repair, you need to identify the cause of the breakdown.

Question:

Hello! I apologize in advance for organizing a separate topic (if this doesn’t quite suit someone) and I want to warn you that my story will be long with all the details of what happened

Thank you for your attention. So, the car is a VAZ 2109 carburetor, 1989.

For a long time the car did not start, after numerous searches for the cause, the entire spark formation system, the gas supply system, as well as the working ability of the carburetor were clearly checked, and some parts were replaced in parts, the engine still did not start, then it was decided to contact the service center. The master said that a key had fallen off, put it back in place and said that it was very lucky that the engine was in order. I got home, everything was fine. Then, before the next trip, I started the car, it starts well, the engine runs and after 15 minutes it stalls, this continued several times. Some complained about a faulty switch. Then, once again, when I tried to start it, I discovered that the oil was gushing heavily. I contacted the same master. He said that that’s it, the engine had outlived its difficult life, a major overhaul was needed and outlined the picture of what had happened. So, at one fine moment the oil seal flew out, it was not noticed in time. The oil got into the engine, mixed with gasoline and gases, and this lasted for about 2 months. At one point, while driving, a key fell off, the timing belt flew several teeth and the valves were bent. Next, my friends recommended one good master to me. I called him and described the situation, he said that we need to look, perhaps it is not necessary to do major repairs and it is possible that it will cost 5,000 rubles. But in any case, it’s time for a car manufactured in 1989 to undergo a major overhaul. Price from 15,000 rubles to unknown. And now I am concerned about an important question: what is the maximum amount? How to make sure that the master calculates the amount for the work and parts actually performed during the repair. And maybe someone can recommend a good craftsman in Nizhny Novgorod who is honest about replacing parts and calculating the cost of services? Thank you in advance and I apologize if in some places I somehow presented the information incorrectly, since I know the structure of the car very superficially.

How to determine a motor malfunction

The engine of a VAZ 2109 car, together with the gearbox and clutch, constitute a power unit, which makes up a single unit located on three rubber-metal elastic supports fixed in the engine compartment. Some faults can be diagnosed independently:

• Increased clearances in the assembly, very early ignition or insufficient oil pressure are indicated by a metallic, dull sound of the crankshaft main bearings.
• A large gap in the bearings or insufficient oil pressure can be indicated by a sharp knock in the connecting rod bearings.
• Replacement of pistons or piston rings will be necessary when the piston knocks, which is caused by its beating in the cylinder.
• A broken valve spring or mismatched clearances can be characterized by a uniform, constant knocking sound in the valves. To identify worn elements, you need to perform a visual inspection of the unit.
• The ingress of foreign particles under the oil pressure valve and failure of the oil pump can be determined by insufficient oil pressure at idle when the engine is warm. When using low-quality motor oil, such problems may also arise.
• Excessive pressure in the oil lubrication system indicates that the pressure relief valve is stuck or its spring is too stiff. After replacing the appropriate elements, this problem is eliminated.
• An increase in oil consumption can be caused by increased wear of piston rings, engine seals, valve stems, guide bushings, and oil seals.

Auto repair

Any of the listed malfunctions requires VAZ 2109 repairs - periodic or major.

Periodic car repairs

Regular car maintenance involves maintaining the normal operation of all components and parts of the car. In this case, the VAZ 2109 may not need major repairs for a long time, which will significantly reduce the costs of operating the car. The frequency of maintenance and repair of a VAZ 2109 car must be performed:

• Before winter and spring, the technical condition of the car is checked.
• After 15,000 kilometers, the oil and filter must be changed to clean it.
• After a run of 30,000 kilometers, the fuel filter is changed.
• Brake pads must be replaced as they wear out physically.
• Every 10,000 kilometers it is necessary to carry out diagnostics of the chassis.
• After 60,000 kilometers, the timing belt needs to be replaced.
• Spark plugs are changed every 30,000 kilometers.

This work is necessary to prevent possible malfunctions. For more serious interference with the operation of the car, you need to use the VAZ 2109 repair manual. If you follow all its basic recommendations, the car enthusiast will be able to repair the car with his own hands without much effort.

Engine overhaul

The need for major engine repairs may be indicated by:

• Instability in the operation of the unit.
• Extraneous noise.
• Tapping at the knot.
• Increased fuel consumption.
• Reduced engine power.

When performing work, the technical characteristics of the unit are restored to values ​​that correspond to the original indicators. To do this, the engine is pulled out of the VAZ 2109, disassembled, and a defect list is drawn up. All parts and assemblies are carefully examined, measured, the necessary gaps are measured, and the sequence and cost of repairs are determined. Parts that need to be restored are repaired, those that have become unusable are replaced with new ones. According to the rules, a major overhaul of the VAZ 2109 engine must be done after the car has traveled 150,000 kilometers:

• Engine repair begins with replacing rings and pistons.
• The cylinder block is bored.
• The crankshaft journal is ground.
• The starter is visually inspected.
• The serviceability of the generator and ignition distributor is determined.
• The thermostat, pump, hoses, and drive belts are replaced in the cooling system.
• The radiator is cleaned of dirt and washed.

Advice: During repairs, it is imperative to change all rubber elements.

All units are assembled in the reverse order of their disassembly.

Tip: When replacing the cylinder block, the bearing housing assemblies also need to be replaced. This is due to their joint processing.

Repair of the VAZ 2109 cylinder head requires special attention:

• The carburetor is removed from the intake pipe (see Repairing a VAZ 2109 carburetor at home).
• Its gaskets are removed.
• The carburetor heat insulating shield is removed.
• The cylinder head is removed from the car.
• The warm air intake pipe, exhaust manifold, and intake pipe are removed. The gaskets are removed.

Tip: The sealing gaskets must be removed carefully. If they are not damaged, they are reused.

• The spark plugs and coolant temperature sensor are unscrewed.
• The camshaft is pulled out.
• The tension roller and the thrust washer located under it are removed.
• The valves and stops for them are removed.
• All parts of the assembly are washed in gasoline, wiped, and dried.
• They are visually inspected and their serviceability is determined. If necessary, they are repaired or replaced with new ones.
• Assembly of the unit is performed in reverse order.