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Pinking
If you thought that when the engine appeared sounds that did not exist before, immediately check that all was in order with the engine. Most often knock in the engine linked to serious failures to diagnose and resolve them will have to disassemble the engine in a garage or service. However, you can try to determine the cause of knocking yourself to decide to go to the car service driven or towed.
| Fig. 3.1. Listening area knocking in the engine: 1 - main bearings; 2 - connecting rod bearings; 3 - piston pins; 4 - pistons; 5 - valves |
A WARNING Should you have the slightest doubt in the results of self-diagnosis, obtain the towline. Serious repair damaged engine will cost more than the towing service. |
Knock main bearing (tapped in the bottom of the cylinder block) - a very dangerous; immediately stop the engine in auto repair garage or have to go in tow. Knocking low tone markedly enhanced under load and with increasing engine speed. Often it is accompanied by the appearance of oil pressure (warning light oil pressure is almost always lit). A knock on the connecting rod bearings (tapped in the middle of the block of cylinders) - a very dangerous; immediately stop the engine in auto repair garage or have to go in tow. The sound of the rhythmic, clear, metallic, medium tone. Significantly increases with the load and disappears completely when disconnecting the spark plug. Knock the piston pin (tapped the top of the cylinder) - dangerous; without loading the engine, drive to auto service garage or own. The rhythmic, high-pitched, with a sharp metal shade, can be heard in all modes of operation of the engine and increases with increasing load on the engine. Completely lost when disconnecting the spark plug. Knock worn pistons and cylinders (tapped in the same part of the engine, and the sound of the piston pin) - harmless; without impacting the strong engine, drive to auto service garage or own. Sound, as of pottery. Especially good to hear the engine is cold, as warm decreases or disappears. Knock valves (tapped in the upper part of the engine in the area of head cover) - non-hazardous, takes you to the car service garage or own. Metal knock on the background of a deaf noise. Good listened to small and medium engine speed from the cylinder head above the locations of the valves. Knocking - hazardous, but are usually eliminated dressing quality fuel. Avoiding heavy load of the engine, drive to auto service garage or own. Voiced metal knocks, usually occurring during acceleration. The reason - incorrect installation octane-corrector, the use of low-octane fuel, motor overload if you turn too early upshift, a significant soot formation in the combustion chambers. You must apply a special fuel additive to remove carbon deposits on valves and combustion chambers.
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