Tractor Repair: case 5140, case 5140, air leak

Question
i have a 5140 case , 1993 6000hrs , which is capable of a hard days work , however if the fuel tank is below half at night and  left overnight she wont start in the morning.
it seems to be ok if tank is over half full?


Answer
Hello,

  Two things that can cause this.  These tractors are notorious for fuel lines that deteriorate and cause an air leak between the fuel tank and the lift pump on the engine.  The lines are mostly steel, but there is a rubber hose where they attach to the lift pump and return line, and on top of the fuel tank where they attach to the tank.  To access the top of the fuel tank, remove the seat base and work through the hole in the floor.  The rubber usually is cracked and rotten which means the entire fuel line should be replaced.  Also, the lift pump could have failed.  Open the bleed screw on the filters and operate the lift pump to see if it will pump any fuel.  If not, replace it.