My suggestion to you would be to go to Harbor Freight Tools and buy this http://www.harborfreight.com/cpi/cta...emnumber=93983 instead of a new p/u. Alot of SV owners, including myself use the stock rudder water p/u. It works just fine in most cases. With the thermometer, you'll find out if you need to make changes in your overall setup, or not.

I would also recommend removing the silicone water jacket and turning it inside out and inspecting the holes for blockage. This has been the biggest problem with the cooling systems on these boats.

Have Fun!