Difficult start of the diesel engine

  1. Low compression in the engine cylinders
  2. Wear of the plunger pairs of the fuel pump
  3. Thickening of diesel fuel at low temperature
  4. Injector nozzles contamination, malfunction of injectors, black exhaust smoke
  5. Starter malfunction or weak accumulator
  6. Malfunction of injector advance system
  7. Malfunction of the glow plugs control system and breakdown of glow plugs
  8. Fuel filter contamination
Изображение проблематики


  1. By low compression warm start of the diesel engine is only a bit easier than a cold start. Moreover the engine start is not harsh, explosive, but backward. The reasons for low compression are cylinders wear, wear or destruction of piston rings, piston rings sticking, gapping or burning-out of valves, burning-out of the piston top.
    In case of piston ring sticking it is recommended to use one of the products: Anticarbon - anti-carbon engine cleaner introducing it into every cylinder through the glow plugs or openings of injection nozzles. It is recommended to use the product Atomex TotalFlush - oil system cleaner before the change of motor oil. By uncritical wear of cylinders and piston rings it is recommended to conduct the full treatment of the engine oil system with the product Revitalizant® for diesel engine or Atomic Metal Conditioner Maximum with 1 Stage Revitalizant®.
  2. The second and the most common reason of the difficult warm start of the diesel engine is wear of the plunger pairs of the fuel pump. By the plunger pairs wear in high pressure fuel pumps the cold fuel can be pumped with the plunger, but as soon as the fuel warms up, it becomes more fluid and cannot be pumped in the necessary volume for the regular engine start.
    Uncritical wear of the plunger pairs of the high pressure fuel pump can be restored with the help of previous flushing with the special cleaning agents and the following treatment of the diesel engine fuel system with Revitalizant® for fuel equipment.
    Recommended fuel system cleaners for diesel engines:
    • VERYLUBE fuel system cleaner (Diesel)
    • Diesel-Lux - complex fuel treatment
    • Multi Cleaner (Diesel) – fuel system cleaner for diesel engines
    • F8 Complex Formula (Diesel) – protection of diesel engine
    Recommended XADO gel revitalizing agents for restoration of worn plunger pairs of high pressure fuel pumps:
  3. In order to decrease the temperature of the diesel fuel thickening by 7-12°С, it is recommended to add the following product to the liquid diesel fuel regularly at the ambient temperature not higher than 5°C:
  4. By severe contamination of injection nozzles regular application of fuel system cleaners for diesel engine stated in p.2 is recommended.
    Black exhaust smoke by engine operation can be a result of critical amount of contaminations in the diesel particulate filter (DPF).
    By malfunction, the injection nozzles should be checked on the stand and, if necessary, changed.
  5. By any malfunction of the starter, it should be repaired. Weak accumulator should be charged or replaced.
  6. Malfunctioning advance injection system should be checked and repaired by specialists.
  7. Malfunction of the glow plug control system and failure of heating plugs are eliminated with the help of functional check of glow plugs or, if necessary, by their replacement.
  8. In case of fuel filter clogging, it should be replaced and the following preventative cleaning of the fuel system should be conducted with the help of the cleaning agents, stated in p.2. (another replacement of the fuel filter may be necessary).


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