3-way fuel valve HELP

[Blue_Runner]

I bought an additional above deck tank to fit under my bench seat. I bought a brass 3 way valve online. Hooked it all up - when I turn the selector know it spews fuel from the selector stem! So I got a refund, bought another brand at the local marine store. Hooked it all up - same sh!t!!! Now I have to take it back too.

What do you suggest? Will the brass ball valves for h2o systems at Lowes work for fuel? I can piece something together - there's got to be something out there. I'm getting tired of looking....help!