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Air Regulating Valve

NOTE: There is no simple way to test the idle positioner (air regulating valve).
  1. With engine at idle speed (690 RPM), screw in throttle by-pass screw completely when engine in running at steady idle speed. After brief deviation the idle speed must return to 690 RPM.
  2. Connect center connection of air regulator with a 12-volt power supply. Connect outer connection with ground. Air regulator must turn against stop. Exchange outer connections. Air regulator must turn to other stop.
  3. Connect a new regulating valve on the wire plug to check activation of air regulator from the control unit. Air regulator must vibrate noticeably (frequency activation) with engine running. If engine speed is boosted with the by-pass screw, the air regulator must move in closing direction. Air regulating valve must turn in opening direction when engine speed drops. If not, replace air regulating valve.
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