I have a 2000 90 Evenrude outboard. There is a valve in one of the fuel lines in the asmembly. It is a solid one piece t with a screw valve. fuel is squirting out under high pressure. I assume it is some kind of primer valve? I have had a hard time idnentifying this part. Can I buy just that t valve or do I have to buy a whole new asembely? Im not sure what it is for. Thanks