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Over-Run Valve Test

  1. Loosen hose clamps at air filter back plates. Remove inlet hoses from back plates. Block inlet ports and start engine. If idle speed is now correct, reconnect 1 of the valves. Start engine.
  2. If idle speed is not correct, connected valve is faulty and requires replacement. If idle speed is correct, reconnect second valve. If idle speed is not correct now, the second valve is faulty and must be replaced.
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