Fuel Starvation Issue Carbureted 1987 5.0

[65-Fstbk]

I took the car out for a drive, stopped and then when I returned it would crank but no fire.
Opened the hood and there's no fuel in the filter so I thought, hmmm out of gas (another story with gas gauge/sending unit - see end)
Got gas and put it in but it was not empty as got less than 15 litres in before it spewed back on me.
Got in and it fired up so I thought well that's kinda weird.
So now I am checking and I can drive it but when I open the hood there's no fuel left in the filter. I can start it and it will run but the fuel filter has nothing in it. It's like the motor is just barely getting enough to run but I can drive it.
Can anyone offer up suggestion on what the issue may be here?


Motor is a 1997 5.0L converted to carburetor.
All accessory parts were new...mechanical fuel pump, carb (Quickfuel slayer 600), fuel rails to carb, fuel tank, fuel lines (3/8")
I also put a new sending unit in the tank but tested the float in water first and found it had a leak. I boiled off the water inside the float and then soldered the pinhole. I think there must still be a small leak in it b/c over the winter the gauge has now stopped moving more than a hair so I think the damn float has sprung another leak.

 

[Mcmahst]

When you replaced the sending unit, did you notice the condition of the fuel inlet filter? Since you’ve replaced all of the parts from the fuel to the engine, you either have a defective fuel pump or a restricted fuel line or filter. Also, I don’t believe that engine came with a mechanical fuel pump, so did you add an eccentric to the front of the cam? That may be a dumb question, but I have to ask.

 

[65ShelbyClone]

Fuel pump eccentric was the first thing I thought of. The EFI engines just have a little oil slinger in place of an eccentric. It might drive the pump a little bit and maybe for a little while, but it's going to fail if that's the case.