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.
What are the signs that indicate the need for major repairs?
To draw conclusions about the need to repair the VAZ 2109 engine, diagnostics are carried out and on its basis a decision is made as to whether it is worth rebuilding the entire power plant or whether it is enough to repair several specific components so that the power plant gets used to them and operates as usual. A deeply erroneous opinion is that the higher the mileage of the car, the closer the engine is due for a major overhaul.
However, the timing of a major overhaul is delayed if the car has been well cared for, quality maintenance has been carried out, and air filters, technical oil and radiator coolant have been changed in a timely manner. In this case, even if a frightening figure with many zeros appears on the odometer, which shows the number of wheel revolutions, you should not immediately think about overhauling the engine. When the operation of adjacent power plant systems does not raise any complaints, there is no need to rush to thoroughly repair the power plant.
But if the owner of the car neglects the needs of his iron horse: he does not technically maintain it and forces the car to move in conditions for which it is not intended, for example, takes part in races. Very often, after such extreme driving conditions of the car, it will soon urgently need major repairs.
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.
Certain criteria are used to judge whether a VAZ 2109 engine needs to be overhauled:
- the first and most important sign is an increase in engine oil consumption, which ambiguously indicates practical wear of the piston rings; it is necessary to reconsider the guide bushings and oil deflector caps that have not developed their technical capabilities;
- The final life of the crank assembly, the most important of all engine parts, is checked by measuring compression in the cylinders. For this purpose, the pressure meter is dismantled and a pressure gauge is screwed into place - the power plant must be idling during the procedure. Readings are taken and the indicators are compared with control parameters - if the figure is much less than the control one, with a high degree of probability we can conclude that the bearings and hydraulic pump have exhausted their service life and require immediate replacement with new spare parts;
- With characteristic tapping sounds and unstable operation of the power plant at idle, the consumption of an increased amount of gasoline than usual and the inability to achieve full power in the operation of the power plant is recognized as a disorder in the operation of the engine. These moments signal problems in the units around the power plant, but based on the complex of all the signs, it is clearly possible to conclude that a major overhaul is to be done in the near future. When trying to delay major repairs, you need to diagnose the power plant, replace one of the unit parts, or simply tune the engine for full operation. If a set of such measures does not work and the problems remain, it will be almost impossible to dismiss the overhaul of the power plant. Unless the owner completely gives up on his iron horse and puts it in the garage.
Stages of engine overhaul repair
On the eve of a major overhaul, it is necessary to draw up a detailed action plan:
It turns out which VAZ 2109 engine repairs you can do yourself, and which ones you must trust to a car repair mechanic. Necessary:
- choose a place for major repairs - in the best case, it is carried out in the pit of your own garage;
- choose a decent lifting mechanism with slings for securing loads - it helps to remove the power plant unit;
- the engine parts that have been removed must be placed in special trays that are suitable in size for the engine;
- You should not purchase spare parts for the engine in advance - having removed them, you can come to the conclusion that they have become unusable and only then go to the auto store for spare parts;
- if the engine is in very poor condition, a second-generation power plant is immediately purchased complete with a cylinder block for a complete replacement;
- it is necessary to calculate your financial potential and clearly calculate how much time it will take for major repairs, since this is a very long-term undertaking.
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.
Stages of assembling a power plant after a major overhaul
When repairing a VAZ 2109 engine with your own hands, you will notice in the video that:
- all operating fluids are drained and attachments are removed;
- the power unit is separated from the gearbox, the block is removed using lifting mechanisms and placed on a pallet of a suitable size;
- the block head and the crank mechanism are twisted, and the places where the caps and bearing shells were located are marked, so that later they can be returned to their place;
- parts are inspected - everything that can still work is cleaned, lubricated and returned to its place, and rejected parts are replaced with new spare parts;
- when the power unit unit does not need to be replaced, it is cleaned, and special attention is paid to the grooves and supports for the crankshaft;
- installing a block of liners on the stock in full accordance with the marks that were made earlier - the antennae of the liners should effortlessly fit into the grooves of the stock;
- the crankshaft is cleaned, blown with compressed air and placed on supports;
- the half rings for the stop are lubricated with machine oil and secured with grooves to the cheeks of the shaft;
- a metal half-ring is attached to the top of the front part of the middle stock - another ring is mounted on the back side; you need to make sure that the half rings do not protrude beyond the ends of the bed;
- installation of the shells in the main bearing caps is carried out exactly according to the marks that were made earlier - it is prohibited to swap them, but it is necessary to ensure that the antennae fit into the grooves on the caps;
- The main bearing caps are mounted according to the preliminary marks - do not forget that there are two of them on the second and fifth caps;
- assess the degree of wear of the fastening bolts and if there is severe deformation, they are replaced with new ones, the fastening bolts are inserted into all holes, but tightened in a strictly defined order at an angle of 120 degrees;
- the condition of the pistons group is checked - it can be reanimated, but if it is severely worn, it is better to buy a new one; Before installing a group of pistons, you should make sure that they are correctly oriented in relation to each other;
- The piston rings are crimped with a special mandrel, then a piston with a connecting rod without a bottom cover is installed - and here it is important, when installing a new piston group, to take into account the factory marks, and the old marks made earlier by the owner will no longer be noticeable;
- the connecting rod is inserted into the crankshaft journal, the bearings are inserted into the mounting caps and lubricated with machine oil;
- the connecting rod caps are inserted and secured strictly to the places where they stood before;
- mount and reinstall the oil pressure sensor.
Cylinder head repair
Continuing the repair of the VAZ 2109 engine with their own hands, they begin to repair the engine head. If the diagnostics revealed traces of poor-quality milling, and antifreeze leaked into the oil channel through scratches on the surface of the head. In order to restore the cylinder head, it should be removed and ground - a smooth surface will prevent oil from leaking and losing its professional properties.
Continuing disassembly of the cylinder head, remove the rocker with the spring base and examine the place where the rocker comes into contact with the spring. As the rocker wears out, its upper part becomes noticeably rounded - when installing the rocker obliquely, better regulation of the gap between it and the GDV shaft is necessary. And if the rocker itself is installed at an angle relative to the shaft, then it is no longer suitable and must be replaced with a new spare part. Then the valves and other parts are removed, the shaft and pushers with washers for adjustment are removed.
The condition of newly opened wells with pushers that operate inside them is checked. If the valve guide is severely worn during further operation of the machine, the pusher deviates from the specified trajectory, and the wells cease to be round and take on an unusual oval shape. In this case, it is no longer enough to change only the guides - it is better not to save money and buy a new cylinder head - in extreme cases, the head is processed on a boring machine and the bronze bushing is pressed.
Next, you need to start inspecting the studs and the integrity of the threads on them - if the threads are broken, it is better to replace the stud with a new one. Then the head will easily take its place, because a pin with a poor-quality thread is screwed in with considerable effort, and is even more difficult to unscrew. After restoration, restored or new spare parts are returned to their places along with a new cylinder head gasket.
Determining motor faults
The compact, small-sized engine in the front-wheel drive VAZ 2108 is located transversely in the engine compartment. The gearbox is also located here, which simplifies access to repairing the main components of the car. Criteria by which motor malfunctions are determined:
If there is any malfunction, the VAZ 2108 engine requires repair - periodic or major.
Periodic engine repair
Constant maintenance of the engine consists of maintaining all its components and parts in good condition. This will postpone major engine repairs for the VAZ 21083, which means it will reduce the cost of operating the vehicle. These include:
