Diagnostics of the internal surface of cylinders is one of the most critical stages of maintenance of the power unit. Modern methods allow you to conduct a visual inspection without completely dismantling the engine, which significantly saves time and resources of the mechanic. cylinder-box, or technical endoscope, providing the transfer of the image to the monitor screen.
Optical devices have become standard in car repair shops and motor repair shops, and unlike traditional methods that require removal of the cylinder head, videoscopy gives instant results, allowing quick decision-making on whether to remould, replace the rings or completely bulkhead the engine.
However, despite the apparent simplicity of the procedure, there are many nuances that affect the accuracy of the diagnosis. Incorrect equipment selection or violation of the inspection method can lead to false conclusions. In this article, we will discuss in detail the types of cameras, their specifications and practical applications.
Principle of operation and device of videoscope
The basis of any diagnostic endoscope is a flexible probe with a miniature camera on the end, and inside the probe are fiber optic filaments or electrical conductors that transmit the signal, and light from embedded LED sources illuminates the darkened cavity of the cylinder, allowing the matrix to capture the state of the walls.
The quality of the resulting image directly depends on the resolution of the matrix and the quality of the optics. Videoscope High-end provides a clear picture even in minimal light, which is critical for detecting microcracks. Cheap counterparts often sin with lights and low detail, hiding real defects.
Modern models are equipped with rotary mechanisms that allow you to change the angle of view of the camera, which allows you to view not only the side walls, but also the area under the piston or valves, controlled through a joystick on the device body or software on the connected device.
⚠️ Attention: When inserting the probe into the cylinder, you need to strictly monitor the purity of the tool. The entry of dust or oil from the outside on the camera lens will lead to distortion of the image and the inability to conduct a qualitative diagnosis.
Use protective covers or disposable nozzles on the probe when working with aggressive environments or highly contaminated engines to avoid spoiling expensive optics.
Classification of diagnostic chambers
The diagnostic equipment market offers a wide range of solutions, varying in design and functionality, and the type of solutions that are selected depends on the tasks to be solved, with the main division being rigid and flexible systems, each with its own advantages.
Rigid telescopes are straight tubes with a lens system that provide the best image quality and high luminosity, but their use is limited to straight channels and requires removal of nozzles or candles of a certain size, since they cannot bend obstacles.
Flexible videoscopes, or fibroscopes, are equipped with a probe that can bend, which allows you to penetrate candle wells and explore hard-to-reach places, and inside the probe you can use fiber optic or a digital matrix at the end.
- 🔍 Optical instruments transmit the image over a beam of fiberglass, do not require power at the end of the probe, but have the risk of "broken" pixels when the threads are damaged.
- 📷 Video endoscopes have an electronic matrix (CMOS/CCD) at the end, provide high-resolution digital image and the ability to record video.
- 📱 Smart cameras Connect to a smartphone or tablet via Wi-Fi or USB, convenient for quick diagnosis, but depend on the battery charge of the mobile device.
Criteria for the selection of equipment for ICE
The tool for diagnosing the cylinder-piston group requires a number of technical parameters. Inappropriate equipment may simply not fit into the candle hole or give the desired detail. The first and foremost parameter is the diameter of the working part of the probe.
For most modern gasoline engines, the diameter of the candle is 14 mm, and the hole for it is about 18-20 mm. diameter The cameras should not exceed 6-8 mm to allow for maneuvering and lighting, and diesel engines may be more demanding due to their design features.
The second important aspect is the length of the flexible part. Standard 1-2 meters are usually enough for passenger cars. However, inline six-cylinder engines or V-shaped configurations may require a longer probe to reach the far cylinders without moving the instrument itself.
Do not forget to protect the body from the effects of aggressive media. Inside the engine there are vapors of gasoline, oil and high temperature. IP67better. IP68The material of the shell shall be oil-resistant.
| Parameter | Optimal value | Impact on diagnosis |
|---|---|---|
| Probe diameter | 4.0 - 6.0 mm | Allows you to pass through a standard candle hole |
| Permission | 720p - 1080p | You need to identify microcracks and bullies |
| Illumination | Regulated LEDs | Allows you to remove glare from metal walls |
| Viewing angle | 60° - 90° | Optimal balance between coverage and detail |
Technology of endoscopy of the engine
The process of checking cylinders requires preparation and adherence to a certain sequence of actions: the engine must be silenced and cooled to a safe temperature, so as not to damage the equipment and not to get burned. Before starting work, you must unscrew all spark plugs or injectors, depending on the type of engine.
The camera is entered smoothly, without sudden movements, so as not to scratch the walls of the cylinder and not to damage the probe itself. It is recommended to pre-wipe the threaded holes from dirt and oil. After the camera is inserted, the upper part of the cylinder, the zone of compression rings and the piston skirt is visually examined.
☑️ Checklist of preparation for diagnosis
To get a full picture, you need to turn the crankshaft with a starter or manually (if the design permits) to view the entire circumference of the sleeve, special attention is paid to the upper dead position zone (HMT), where wear is most intense, and the condition of the valves and seats through the holes is also examined.
⚠️ Attention: It is strictly forbidden to turn the crankshaft if the probe is already inside the cylinder and rests on the piston, this is guaranteed to lead to failure of the camera and possible damage to engine parts.
If you want to see the bottom of the cylinder or rod, the camera can be gently lowered below the level of the piston when it is at the bottom dead point, but this requires a highly skilled operator and a flexible controlled probe.
Secrets of image purity
If the cylinder walls are full of soot, the image may be fuzzy. Professional services sometimes lightly decoction or compressed air blowing the cylinders before endoscopy to remove loose particles that interfere with view.
Typical defects and their visualization
The main purpose of using the camera is to detect defects that cannot be detected by other methods without disassembling the engine. On the monitor, the mechanic looks for specific signs of wear or damage. Each type of defect has its own visual specifications.
Bullies are deep scratches that run along the course of the piston, and can be caused by overheating, oil starvation, or catalytic failure, and can be seen as dark or light stripes with ragged edges, and the presence of bullies often requires the unit to be remoulded or the cartridges replaced.
The soda and coke look like black deposits on the walls and bottom of the piston. The thick layer of soda can reduce the volume of the combustion chamber, increasing the compression ratio and causing detonation. The camera allows you to estimate the thickness of the layer and its localization.
- 🔥 Cracks Thin lines, often diverging from holes or edges, can lead to the entry of antifreeze into the oil.
- 🔨 Laceration of the valve - visible through the candle hole as a destruction of the edge of the plate of the valve, accompanied by loss of compression.
- 💧 Oily deposits - shiny oil spots on dry walls in a normal state, indicating the dead rings.
It's important to distinguish between design features and actual damage, for example, chon (the mesh on the cylinder walls) should be clearly visible, and if chon is completely gone and you see a smooth mirror layer, this indicates severe wear or polishing of the walls with a piston.
Interpretation of results and decision-making
The data required careful interpretation. Not every defect meant immediate overhaul. Small risks on a piston skirt could be acceptable for a high-mileage engine, whereas a crack in the lintel between the cylinders was a critical malfunction.
Experts assess the combination of factors: the condition of the hona, the presence of bullies, the color and type of lobe, the integrity of the valves, and on this basis, decisions are made about further operation, chemical cleaning, replacement of the rings or deep repairs. Endoscopy This prevents blind repairs.
Endoscopy is not only about finding problems, but also confirming the health of the engine before buying a car or after mileage.
In some cases, the camera helps to identify the consequences of using poor-quality fuel or counterfeit oils. The characteristic color of the deposits and specific damage can indicate the cause of the failure of the unit, this is especially important in warranty disputes or examination.
Can I check the engine with an endoscope without removing the candles?
No, the cylinders are only checked through special holes, in petrol engines, these are candle wells, in diesel engines, holes under nozzles or candles, without dismantling these elements, access to the combustion chamber is closed.
Does Endoscopy Affect the Vehicle Guarantee?
Camera-based diagnostics, done carefully and without breaking engine seals, are not grounds for warranty relief, but if candle threads are damaged or the probe leaves scratches, the dealer may refuse warranty service.
How often should I check the cylinders with a camera?
An endoscopy is performed when symptoms of malfunction (compression has fallen, oil consumption has increased, three engines) or when buying a used car to assess the condition of the engine.
Will the camera show the state of the piston rings?
The only way to see the rings is if you lower the camera below the piston level, which is difficult and risky, but indirect signs, such as rings, can be diagnosed by the nature of the grooves in the piston and the absence of chona in the top of the cylinder.