Today while servicing my Boat for the season I found out that I have no water pressure to the engine. I didnt even realize that the ECU monitored water pressure. There is no gauge but there is a light with an obnoxious buzzer followed by a rising engine temp gauge after about 2 or 3 minutes. When this buzzer is going off I also noticed that the engine will not rev above 2k or so. I sure wish that I had the manual for this boat. The ECU on this thing controls a lot of stuff. It would be nice to know the ends and outs. Anyway, I brought the boat back to the house and pulled the outlet hose off of the seawater pump (I believe that is what it is called) and started the engine with the ear muffs on. No water at all coming out of the seawater pump. I then pulled the pump off and removed the backing and found that the impeller had fragged. A closer look in the outlet pipe and I pulled out 3 pieces of rubber from the impeller. I do have the outdrive service manual and I cannot find anything in the lower unit (like a mercruiser) that looks like a water impeller. Does the Yamaha I/O not have one? <br /> My question is, once I find a new pump (worried about finding one) is there a priming procedure or are ear muffs going to work? Anyone know a place in the Shreveport, LA. Area that knows these rare I/O? How about a good place online to find parts for this thing? It has been rock solid reliable. This is the first failure and I have not found anyone who know these things. Most dealers I talk to look at me like I am nuts when I tell them that I have a Yamaha 4.3 I/O.