I am looking at a Ranger boat with the Mercury XR6 engine which has a total of about 20 hrs time. After cold starting, there is not a stream of water coming from the discharge just below the power head immediately but starts after it runs for a minute or three. I can feel slight air pressure when I place my finger over the hole but it does continue after the short warming period. Just wondering if this is a normal condition or something that needs attention. Thanks in advance for your input.k