My ksb valve is leaking and it looks like it is coming from the nut near the front of the engine. Is this possible and can it be resealed?

 

Clean it up real good (brake cleaner and a good blast from the air hose) and check to be sure where it leaks, a lot of them have been leaking from the pressure control valve on top of the pump. Jim Lane wrote an excellent how-to on fixing that leak, it's in the sticky.