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How to determine leaks in closed systems

Diagnose vehicles, determine leaks and their location

Leakfinder for diagnosing leaks in closed systems

SMT 300

The size of a leak and its location can be determined in two steps:

  • The device with the optional accessories is suitable for investigating leaks in fuel and exhaust systems.
  • The smoke that is generated can also be used to search for leaks in door and window seals.

When investigating leaks in a fuel system, only inert gas (non-combustible, CO2, or nitrogen) may be used. An “inert gas pack kit” (pressurised gas bottle and adaptor) can be ordered separately. The pressurised gas bottle is supplied empty and must be filled by a specialist supplier of inert gases.

You can also order a nitrogen regulator, which is preset to 7 bar, for use with larger nitrogen bottles in the workshop.

A cylinder hose, which can also be ordered separately, is required for connection to the SMT-300.


  • The leak diagnostic device is suitable for tests on fuel vapour return systems as well as other applications.
  • You can test closed circuits, such as intake and exhaust systems, as well as find leaks that let in wind and water.
  • By using the integrated test mode, you can check closed systems without smoke initially and then introduce smoke as needed. You can also regulate the amount of smoke, which makes it easier to find small leaks.
  • This device can be used to ensure that the vehicle system is functioning properly and to prevent any damage.

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