Well there are two possible reasons that stream looks like that.<br /><br />1. Crud in the line, take a small piece of wire and run it up though there and see if it gets better.<br /><br />2. Replace the waterpump.
It is definately too weak.<br /><br />Listen to Nathan and get it right - you may be running with insufficient cooling and THAT, my friend, could end up costing you an arm and a leg (+ an emergency at sea).
