Depends on which abc engine it is. I can't tell from your post if you realize that "ABC" refers to the type of construction and not a brand. Perhaps you do. Some abc engines are very reliable. Some, not very reliable. ABC engines can be a little more difficult to start than ringed engines because they rely on a tight piston-to-cylinder liner fit for compression. You may need an electric starter. That said, they are not necessarily difficult to start.

What is the trainer, what is the engine and what is the radio? We will be glad to advise you on this purchase and hopefully help avoid the disaster of your last purchase.

-Scott