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Check of the automobile before sale
Certification of the automobile after failure
Computer diagnostics of a forward and back suspension bracket
Diagnostics of stability of automobiles
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Automobile Inspection and Diagnosis
Inspection of Engine Compression
One of the most important check-ups, which allows the mechanic to judge the engine's "wear and tear", is the measurement of the compression in each of the engine's cylinders. The check-up is done with the help of special equipment, which is called a compressometer. The engine must be warm during the check-up, with a temperature of 82-92°Ñ, and with the carburetor throttle valves fully opened.
The measurements are taken serially, one by one, in each cylinder. For the measurements to be taken, all the spark plugs are unscrewed, and, in the place of the first spark plug, the compressometer is installed. The evaluator's assistant sits in the cabin of the automobile, presses completely on the gas pedal (with the throttle valves open) and, for the duration of 4-6 seconds, the engine turns over with the help of the starter. The compressometer registers the value of the maximal pressure in the cylinder, which is achieved at the end of the compression step. The norm is considered to be approximately 160 pci.
After that, analogous measurements are carried out in
the rest of the cylinders. If the variance observed in all the cylinders does not exceed 10% (that
is, 16 pci), the compression of the engine is considered
to be within accepted norms.
If the variation is more than 10%, this means that there is heightened wear on the
cylinder, the piston rings or the valves in the engine.
Inspection of Exhaust Fume Leakage
 This check-up also allows the mechanic to evaluate the thinness of the cylinder-piston groups. For the check-up, the piston in the cylinder is brought to the upper "dead" point, which correlates to the "ignition" step. The spark plug is unscrewed and, in its place a hose is fixed, along which air is channelled under pressure of approximately 8 atmospheres. For the duration of one to two minutes, the difference in the level of the coolant fluid in the reservoir is checked. If it has increased, this means that there is increased wear on the engine.
Chemical Means of Checking Exhaust Fume Leakage
 An increased level of carbon dioxide gas in the coolant fluid means that there is leakage of gases from the cylinder-piston group, that there is possible damage to the lining of the cylinder head or that there is the appearance of a crack in the cylinder block. The check-up is carried out by adding a special chemical indicator to a sample of the coolant fluid. A color change indicates the presence of carbon dioxide gas and, therefore, leakage of gas in the engine.
Inspection of the Automobile's Paint
The inspection of the automobile's paint is carried out in two
stages.
First, a visual check is made for the presence of damage, dents, scratches, rust, blistering and flaking of the paint. After that, a special electronic device is used to measure the thickness of putty and filler, as well as the paint and varnish covering between the metal of the automobile's body and the contact surface of the device. The measurements take place in 4-5 points on the top, doors, and side panels of the automobile. It is possible to judge the condition of the paint and varnish covering of the automobile from the results of the check-up. It's also possible to see whether repairs have been carried out on the body of the automobile or not.
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