There are many uses for a small inspection camera including checking condition of pistons, cylinder walls, chamber debris and valves through the spark plug hole. Below are some other useful ways to use the camera.
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Check your belt tension without lying on the floor to see the scale on the belt guard
Camera mounted to a dial indicator magnetic base 1)	Note position of the belt in the window with no force applied 2)	Finally, the belt with 10 ft/lb applied using the belt tensioning tool 3)