When I was younger, I used to suffer from mechanophobia, the fear of machines. I was incredibly afraid of them. Any kind of loud machinery, small and large, from power tools like saws to lawn mowers to car engines and so on. Trucks and buses used to scare the crap out of me if I was standing near the engine part when it was turned on. As I got older I managed to overcome this phobia by forcing myself to mow the lawn (parents usually did it). Once I held the lawn mower and started mowing, I realized I had full control over the machine, I was the master, not the other way around. Trying to drive a car also helped. With time, the fear dwindled more and more. Nowadays, I still sometimes feel uneasy around loud machinery, but nowhere near the fear and utter dread I used to feel when I was younger.
Today I just suffer from acrophobia, the fear of heights. I tried "beating" this phobia as well, but no matter what I do, I can't overcome it, so I just live with it. Though this one is a pretty common phobia.