Power Lawnmower Features

Richard L. Parish, PhD, PE

Power lawnmowers are available with a wide array of features. Some of the features are very helpful; some less so.

Safety Features: The Consumer Product Safety Commission mandates several safety features. The mower blade must stop when the operator releases an operator presence control on the handle. On less expensive models, releasing the control lever stops the engine; on more expensive models, releasing the lever disengages a blade clutch and engages a blade brake. All mowers must have shields at the rear to prevent inserting toes under the deck. There are also standards to protect operators and bystanders from thrown objects.

Power Source: Power mowers can be powered by an electric motor or a gasoline engine. Electric models are generally smaller. Most electric models require a cord, although some battery models have been developed. Few electric models are self-propelled. Electric models are best suited to very small lawns. Gasoline engine models offer easier maneuverability and generally wider cutting widths, but require more maintenance and make more noise. The engine can be 2-stroke or 4-stroke. Two-stroke engines tend to be lighter in weight, but require you to mix oil with the gasoline.

Power: Mower engines have become more powerful over the years. A few years ago, 3-32 hp was typical for most mowers. Now, 6-8 hp is common. Part of the increase is due to the popularity of self-propelled mowers, but mulching has become more popular and requires more power. If you are buying a self-propelled mower for mulching, look for the more powerful models.

Wheel Size: The larger the wheels (tires) on your mower, the lower the rolling resistance. This is true whether the mower is self-propelled or not. If you have deep thatch or a hilly lawn, a high wheel mower will be especially helpful. A high wheel mower will be easier to push and, if self-propelled, it will pull itself better. The disadvantage to high wheels is that high-wheel mowers tend to be longer and thus more difficult to maneuver in close quarters.

Method of Self-Propulsion: Some self-propelled mowers drive the front wheels and some drive the rear wheels. Front wheel drive offers easier turns without having to disengage the drive - just push down on the handle to lift the front wheels while you turn. Rear wheel drive may be more effective in some cases since the rear wheels carry more weight and thus will have better traction. You should also pay attention to the drive mechanism. Some mowers use a belt or friction drive that is difficult to adjust and prone to slippage. Test out a mower before buying it and see how much effort it takes to hold it back while it is trying to propel itself. If very little effort is required, the mower probably won’t pull itself in heavy grass, deep thatch, or on hills. You should also check to see that the propulsion system completely stops when disengaged and does not creep.

Handle Length: Manufacturers have tended to make handles longer to keep the operator further from the mower. Also, many mowers now have rigid handles that won’t move up and down. These features are desirable from the safety standpoint, but make mowers much harder to maneuver.

Discharge, Bag, or Mulch: Mowers can discharge clippings to the side, mulch clippings, or bag the clippings into a rear-mounted or side-mounted bag. This is the subject of a separate article.

Quality: There is a wide range of quality in lawnmowers. If you are buying a simple, non-self-propelled engine-driven model, quality is less of a concern than if you are looking for a self-propelled machine with a blade clutch. The more complicated types of mowers are more susceptible to reliability problems and thus warrant more concern over quality.

You have many choices to make in selecting a lawnmower. It can be a challenge to optimize both features and price.