Just a SWAG here, but I'd guess that you're running out of oil. It's all in the assemly, with little left in the sump.
It might also be that the "Trap Doors" aren't working . . Which, again. would account for the "Running out of Oil" deal. It isn't letting the oil come back, and it isn't keeping it there once it gets there . .
Note the word "GUESS" . . .