One of the first things to think about when buying a new zero turn mower is the engine. The engine you choose will depend on several factors, including your budget and whether you have hills in your yard. If you have a large yard with a lot of hills, you'll need a strong engine that can handle these types of conditions. The size of the engine is also important. While a larger engine will be more powerful, it may be less convenient to use because it will be heavier and may create more noise. As long as you take your specific needs into account, you should be able to find an engine that meets your needs.