I have a 2000 Merc 225 efi and am getting about 10psi on my gauge while I am running WOT. I just had the lower unit rebuilt and a new impeller installed. When I was running STABIL to winterize the motor recently I was using my garden hose and the ears to supply water. I ran it for about 10 mins this way and the alarm went off. I have 2 questions: 1. is 7-10 psi at WOT enough to prevent damage to the motor and 2. Would it seem normal for the alarm to go off in the driveway. The boat was at a slight tilt downward toward the bow.
