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Torque Converter Transmissions

Prepare the Machine for Test
  • Warm up the engine (emissions change for cold and warm engines)
  • Park the machine into an intake entry with vehicle facing the mine rib
  • Set brakes and chock the wheels
  • Sample exhaust emissions before any after treatment devices, i.e., before catalytic converter, particulate trap, fume diluters, and water scrubber
  • Engine Load Test
  • Make sure no personnel are in front or behind the machine
  • Set transmission gear
  • Full throttle to induce converter stall for about 60 seconds
  • Sample allowing reading to stabilize and record measurement
  • Release throttle and shift transmission out of gear
  • Allow torque converter to cool for a few minutes
  • Repeat the test using the same method every week for comparable results
  • Sampling with CO measurement device at idle, prior to torque stall, will allow for quicker sampling and shorter stall tests
  • Using a tachometer to verify the engine speed at load will help weekly repeatability
  • Evaluation and Interpretation
  • Check for changes in CO concentration against the baseline you have established for the engine
  • Increases in CO concentration level above the established baseline indicates problems
  • Contact MSHA Technical Support for guidance on engine CO information
  • Maintain records to track engine performance
  • A chart of individual equipment emissions plotted over time (weekly)
  • A logbook separated into individual equipment for easy weekly comparison
  • A logbook separated into similar engines