Fuel starvation before tank is empty

[Henrius]

Got my 65 Fury with 383 back from restoration shop after a long time. (Delayed by COVID) I think the rear leaf springs were re-arched to bring the car to level. A new fuel level sender was put in.

I had hopes that the fuel gauge would read accurately, but it was not to be. When the tank is full it registers only 3/4 full. The important question was: what would it read when empty?

Well the other day in the Costco parking lot the car starved out of gas with the gauge between a quarter and half full. I put in 2 gallons from a jug and it started right up. Then I drove it to the pump and the 26 gallon tank only took 10 more gallons! Meaning it starved out of fuel with about 14 gallons still in the gas tank!

I am guessing the new fuel sender unit does not have a long-enough pickup tube to reach the bottom. Could leveling the sagging rear end caused the gas in the tank to shift away from the end of the pickup tube? I am confused what caused this problem.

 

[CBODY67]

The fuel pickup should be near the front of the tank. The lowest area of the tank, too. Which raising the rear ride height would have certainly made it the part of the tank which would always have fuel, it ANY was in it. Is the bottom of the tank flat or concave, in its long dimension?

Where did the new sending unit source from? Or was it a universal/modified fit item? Was the pickup tube length and such compared prior to installation? As the gauge does not read close-to-correctly, I'm suspecting the sending unit was not an exact replacement for the OEM production unit? Or possibly subject to installer error?

Just curious,
CBODY67

 

[HWYCRZR]

You likely have a fuel delivery issue. Did the sending unit get put in and indexed correctly? (Usually only one way or it will leak). Was it the proper sending unit and is the fuel pickup sitting down in the sump where it belongs? If those check out. Have you checked the tank vents since the restoration. Can the tank breathe or did someone plug the vents? Will run for a while but then will create a vacuum and starve for fuel.
Also check your fuel filter. Not sure if you replaced all the lines or tank during the restoration. If not all new, it could have washed the old debris into the fuel filter. Quick check is to pop the filter off and blow through it. Should be easy if not plugged.
Start with the simple things.