I'm having problems getting my freshwater pump to stay primed after sailing. When I'm at the dock the pump seems to stay primed, but if I take it out for a sail almost every time I have problems getting the pump to prime. In the install manual it did note this could be a problem. However, being an engineer I got to figure out why and fix it.. We installed a 12K reverse cycle unit in a 1991 Hunter 30 (under front Vberth). The boat had a 1.5in seacock at the aft end of the boat (head discharge not being used) which is about 2ft aft and to port 1.5ft the prop shaft log (as close to bottom of the boat as you can get). We reduced the output to the seacock from 1.5in to .75in and installed a strainer. From the strainer we ran a short hose red striped to the pump provide in the kit. All the equipment to this point is below the water line. From the pump output we ran hose to the A/C unit under front Vberth approx. 25ft. Then setup the water discharge approx. 7in above the water line. Once the pump is primed at dock the unit can be turned off and on and works fine (even leaving the boat idle for a week (use boat on weekends). However, every time we take the boat out, we have to turn the unit on and off several times to get the pump to prime. Looking at the hoses at the pump there is air in the line (not a lot). I'm trying to determine if the line is getting a suction (back flow) on the line, or air is being brought in due to the prop, or what? I'm open to any ideas you guys might have. Thanks Jim jim.wharton@fnc.fujitsu.com