I bought this engine about 12 years ago and it just sat on my shelf until about 3 years ago. I hooked up a battery and buzz coil and used Colman fuel with about 10% WD40. Much to my surprise it started up. It does need some adjustments and fine tuning to get it to run better but it runs. Have decided that since I’ve only messed with it once in 12 years that I should sell it. The flywheel diameter is 4. It has spark plug ignition but you will need your own buzz coil and battery. The item “New Holland hit and miss scale model engine” is in sale since Sunday, April 17, 2016. This item is in the category “Business & Industrial\Light Equipment & Tools\Stationary Engines\Engines”. The seller is “fay68″ and is located in Wheatland, Iowa. This item can be shipped to United States.