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Leak Test Using Smoke Machine

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  1. Using Rotunda Dual Purpose Diagnostic Leak Detector or equivalent, install the leak detector in the cooling, intake, exhaust or EVAP system. Follow the Rotunda Dual Purpose Diagnostic Leak Detector manufacturers instructions to assemble and install the leak detector. Follow the Rotunda Dual Purpose Diagnostic Leak Detector manufacturers instructions to operate the leak detector.

    See Below to view Rotunda Dual Purpose Diagnostic Leak Detector assembly and instructions 

  2. When smoke testing cooling systems:

    • Remove the spark plugs.

    • Remove the oil fill cap.

    • Drain the cooling system. REFER to the Engine Cooling System Draining, Vacuum Filling and Bleeding procedure in the Engine Cooling Service Information General Procedures for the engine being tested. To optimize the efficiency of the smoke test, it is necessary to remove as much coolant from the system as possible. Any coolant left in the system can restrict smoke from identifying a possible leak path. Use the Air Only feature on the Rotunda Dual Purpose Diagnostic Leak Detector installed on the degas bottle to pressurize the cooling system to force any residual coolant out of the system through the radiator drain valve. Disconnect the lower radiator hose at the radiator to remove any residual coolant.

    • Reconnect the lower radiator hose.

    • With the radiator drain valve open, follow the Rotunda Dual Purpose Diagnostic Leak Detector manufacturers instructions to operate the leak detector until smoke visually exits the radiator drain valve. Close the radiator drain valve.

    • Visually inspect the cooling system for smoke escaping from the hoses, pipes, clamps, joints and all components of the cooling system.

      See Below to view coolant leak diagnosis using Rotunda Dual Purpose Diagnostic Leak Detector 

  3. When smoke testing intake systems, visually inspect the intake system for smoke escaping from the intake hoses, pipes, clamps, joints CAC and turbocharger.

    See Below to view vacuum leak diagnosis for naturally aspirated engines using Rotunda Dual Purpose Diagnostic Leak Detector 

    See Below to view vacuum leak diagnosis for turbocharged engines using Rotunda Dual Purpose Diagnostic Leak Detector 

  4. When smoke testing exhaust systems, visually inspect the entire exhaust system for escaping smoke. Inspect the mufflers, resonators, catalytic converters, pipes, clamps, joints and turbochargers.

    Click here to view exhaust leak diagnosis using Rotunda Dual Purpose Diagnostic Leak Detector 

  5. When smoke testing EVAP systems, visually inspect the entire EVAP system, purge valve, tubes, hoses, fittings, joints, fuel tank and emissions canister.
  6. Note normal leak points. Disregard points in the intake, exhaust or EVAP systems that normally vent to the atmosphere such as exhaust moisture drain (weep) holes, or wastegate linkage.
  7. Identify the source of a leak. If smoke billows and prohibits a clear evaluation of the source of a leak, turn the smoke machine off and allow the smoke to clear. Turn the machine back on and visually inspect suspected areas for escaping smoke.
  8. REPLACE or INSTALL new components identified by the leak detection test as having a leak.
  9. Road test the vehicle.