78 233 Thunderbird Fuel Tank issue

[Randy Testerman]

My parents are moving back to Fla. so they gave me their boat. Its a 78 233 Thunderbird with a 260 Merc. Fuel lines were totally shot. I noticed that the tank has 2 lines that go into a brass tee then is goes to the water sep. filter. Why 2 lines?? Can one be illiminated?? I have a manual fuel pump and I don't understand why 2 lines would run into s tee then from the tee a single line runs to the filter.

[Randy Testerman]

I guess I should further explain. I am not talking about the fill line or the vent line.

[Jason]

You can use a single line from the tank but be sure to cap where the other line comes out at the tank or else the pump will just suck air. Only reason I can think of for running two lines from the tank into a single is from the factory they probably just use one single standard tank between the single and twin engine boats.