The issue in most cases is caused by an air pocket that surrounds the impeller or pickup intake. From the operator’s perspective, you’ll hear the pump running, but no water will fill the chamber.
First, be sure that you’ve opened the spray head to allow water to flow. If you’re uncertain how to open the spray head, we invite you to view this related post, “How do I operate my aerated bait well?”
Next and assuming the spray head is open but your issue unresolved, move your boat a short distance (preferably on plane), throttle down and allow the water coming towards the boat to “catch up” and reach the transom. In most cases, this “push” from the water will clear the air pocket.
If you’ve moved your boat but the issue remains, you may have a mechanical issue with your pump or some type of blockage within the pickup itself. If you suspect a mechanical problem, reach out to your local CRI dealer for assistance.