I put Sea Foam treatment into the gasoline which appears to have cleaned everything. Now the Idle seems too fast. Can someone tell me how to adjust it down some?
Sure, the idle speed is controlled by the idle stop screw and the throttle cable. You would back off the idle stop screw, and adjust the throttle cable barrel nut to push the throttle closed, until you get the correct speed. Do not adjust any other screws or cables.
Idle speed on a flusher should be about 1000RPM. That will drop to 850-900RPM in the water.