mine is shot, even unhooked and turned off it bleeds heat, has anyone installed a shut off valve for the summer?

 

A properly functioning heater valve will act as a shut off valve, Your diaphragm is most likely shot as this is a common failure point in our cars.
But you can't really just shut it off as it still needs to flow coolant and a shut off would be a big block in line.

 

You could bypass it I would imagine but that's kind of ghetto.

 

Does anyone have a good one to sell? Also looking for a k+n drop in or intake