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Deceleration Valve

  1. Remove hose leading to intake air duct from deceleration valve and plug hose. Start and warm engine to normal operating temperature. Increase engine speed to 3000 RPM for a few seconds.
  2. Allow throttle to snap close, and at the same time, hold finger at deceleration valve nipple (from which hose was removed). Check for suction at deceleration valve nipple.
  3. Now, remove vacuum hose from "T" connector and plug connector. Run engine at 3000 RPM for a few seconds and allow throttle to snap closed. Again, check for suction at deceleration valve nipple. No suction should be felt. If valve operation is not as specified, replace deceleration valve.
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