Here is a link with the flush connectors for the Mercruiser flush kit.
http://www.psepmarineparts.biz/store...nector_kit.htm

They seal when not connected so there is no need for a valve. I just turn the hose on with the quick-connect hooked up. Hook it up to the quick-connect on the motor and start it up. Quick and easy. It back-flows through your outdrive to flush that out as well. You can also flush the engine while it is in the water.

I like it better then the flush kits from Perko with the check valves because there is a lot less to go wrong with this setup.

It plums in-line with your 1.25 inch hose from the outdrive to your water pump. Very quick and easy install (if you have good access).

Nope. Even easier with NO MOVING parts to stick or fail.

I just have a tee plumbed into the hose right before the seawater pump. From that tee, a hose goes up to the hose fittings.
With the motor off and water hooked to the fitting, water will run out the drive. But as soon as I start the motor, the suction from the pump pulls the water into it, and the flow stops going out the drive. So simple, Merc should do it. :)

Only thing to watch is too make sure the cap is secured back on when done, otherwise it will be a air leak and the seawater pump won't pull water thru the drive when in the lake.

I'm actually looking for a quick disconnect like you would see on an air line. I don't mind flipping a valve on the strainer. I just don't want the hose going over the side ( yea I know pet pev). I just want to snap it into the hull side. I may just make one.