Can you substitute bananas for engine oil?

I have heard that unscrupulous people will pack banana peels and sawdust into worn out car gearboxes to stop them from whining long enough to trick a buyer into thinking the car doesn't need serious repairs.
In this episode of Project Farm, I learned that people have used bananas as an emergency replacement for engine oil. How well do they work in a lawnmower? Watch the video and find out!