First and formost, where are the pictures and welcome aboard the nuttiness

If the valve of which you speak is on the water outlet of the pump, leave it there, it serves two things, one, a quick shut off in case of catastrophic hose failure while in the water and two, a Mickey Mouse way of slowing the water flow if your engine overcools and have no way to regulate it..If the valve is in the hose at a tee and there is a hose bib adapter, that is a way run the engine on a garden hose and I do not recommend that particular method, like I said no pic=piss poor help

GT