I have given some thought to this for a replacement to the combustion engine.

In my opinion your model, and what I have been brainstorming have to have some method to either neutralize polarity or reverse it once the polarity push has been achieved. You need either all push or a combination of alternated push then pull.

In theory a magnetic engine is the eternal motion machine. Once implused to start it would have to be neutralized or braked to ever shut down. Think what that would mean for small appliances like a refrigerator, or airconditioner. Anything that needs to run continuously could be created free of the need for electricity.