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Extraneous noises in the engine

Possible reasons / recommendations

  1. Knocking noises and other noises are caused by wear of coupled engines. Rattling and knocking noises in the upper engine section are associated with the operation of the valve linkage and thus indicate excessive air gaps in the valve train, possible wear of control cams, excessive air gaps between valve stems and guide bushings.
    • Replacement of defective parts and/or adjustment of the control device
  2. Frequent "rattling" is indicative of malfunctions in the hydraulic tappets due to contamination of oil lines, leaking closing of the return valve and/or its wear (excessive air gap in the injection element). In a properly working engine, the noise will disappear after warming up, but a damaged hydraulic valve lifter will continue to knock. Therefore, it is first necessary to flush this assembly thoroughly. This can help to determine the cause of the knocking noises: If the problem is contamination, the knocking noises disappear after the oil lines have been flushed. If the hydraulic valve lifters are worn, the noise can be eliminated by increasing the viscosity of the oil or using a denser oil. A denser oil will help seal the air gaps. If the wear on the hydraulic tappets is critical, they must be replaced.
    • Flushing the hydraulic valve lifter oil lines: STEAL VitaFlush for adding to the engine oil (from 200 to 1,000 km mileage).
    • Increase in oil viscosity: Atomex Complex Oil Treatment Anti-Rauch-Additive with Revitalizant®.
    • Application of oil with increased high temperature viscosity. For example, changing from oil with viscosity SAE 5W-40 to SAE 5W-50.

    Experience shows that Verylube TURBO metal conditioner makes it possible to significantly reduce the knocking noise of the hydraulic valve lifters.

  3. Metallic rattle in certain operating modes of a gasoline engine, e.g. B. at excessive loads, are associated with knocking, which can arise from the following causes:
    • Malfunctions of the engine control (ignition too early/too late, malfunctions in signaling to open the injectors, ignition coil spark plugs, etc.),
      • Eliminate engine control malfunctions, adjust engine control, replace damaged elements,
    • inferior gasoline quality,

      to eliminate the consequences of low-quality fuel, as well as improve fuel properties, you can add the appropriate additives to fuel:

      • AtomEx F8 Complex Formula (Gasoline) Engine protection against the consequences of using inferior fuel.
      • Verylube Gasoline Euro+ Additive to improve fuel quality
    • Insufficient fuel level associated with malfunction or contamination of the injectors

      Clean the injectors by adding one of the following agents:

      • STEAL MaxiFlush highly efficient agent for professional installations for cleaning the fuel system of petrol engines.
      • AtomEx MultiCleaner (Benzin) Highly efficient engine fuel system cleaner
      • VERYLUBE injector cleaner Agent for cleaning injectors in petrol engines
  4. Knocking noises associated with glow ignition (the mixture ignites due to hot engine parts due to excessive carbon deposits on valves, pistons and surfaces of the combustion chambers).

    Excessive carbon deposits can be removed with VERYLUBE Anticarbon quick-acting agent for removing carbon deposits on piston rings in petrol and diesel engines. The agent is to be added directly to the engine cylinder. After removing the coking with VERYLUBE Anticarbon, it is necessary to change the oil.

  5. Noises (thud, low-frequency noise, metallic, echoing and repetitive noises) coming from the lower part of the engine in time with crankshaft revolution indicate wear of crank bearings and crank pin bearings, as well as lowering of oil pressure. If the knocking noises are present in the crank bearings and crank pin bearings, then the operation of the engine should be avoided. If the oil pressure in the lubricating system has decreased and the noises mentioned have been made, as a temporary measure when driving the car to the parking lot or workshop (maximum 100 km), you can try increasing the oil pressure by increasing the oil viscosity or using a more dense oil . A denser oil can seal the air gaps and increase oil pressure.
    • Increase in oil viscosity: Atomex Complex Oil Treatment.
    • Application of oil with increased high temperature viscosity. For example, changing from oil with viscosity SAE 5W-40 to SAE 5W-50.


* The product is manufactured separately for petrol and diesel engines.

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