Try this. Open the C-130 ACE. Select the LC-130. Select the option to remove the eternal tanks. Press SAVE. Run FSX and select the LC-130, and check the fuel by remove all fuel. Add fuel using your W key. See if it fills all the tanks. Exit FSX.

Go back to the C-130 ACE. Select the LC-130. Add the external tanks. Press SAVE. Run FSX and select the LC-130, and check the fuel by remove all fuel. Add fuel using your W key.

I'm just trying to see if removing the external tanks and adding them again will sort it out.

Mark