Self-propelled lawnmowers work on a vehicle-like drive system that requires the operator to squeeze a bar (called a "bail") on the handle to engage the mower. Squeezing the bar causes the cutting blades on a self-propelled rotary mower to spin and makes the mower take off. After that, the mower moves forward independently, not requiring your pushing power. You only need to control the direction it goes.
If you release your grip on the bar, the mower stops moving, and its blades stop spinning. You may be familiar with this type of device if you have a hand-guided self-propelling vacuum cleaner; it has its drive doing a lot of the moving for you.
If you've ever wondered how self-propelled lawn mowers work and if they're worth considering for your lawn, read on to learn more.
What Is a Self-Propelled Lawnmower?
A self-propelled device means it has a drive and doesn't require your strength to operate it. You still need to steer the lawn mower since it's not an autonomous robot, but it can save you time and energy.
Self-Propelled Lawn Mower vs. Push Mower
Self-propelled lawn mowers are motorized and drive independently, only requiring you to steer and move along with the device. The machine does the heavy lifting while you guide it along.
On the other hand, a push mower tells you in its name that you will need to use your body strength to push it. Push mowers can vary widely from non-motorized reel push mowers to motorized push mowers powered by battery, gas, or an electric plug. Here are two different types of push mowers:
- Reel mowers: Best suited for small, flat lawns; using no power, only your push strength to turn the axles that push the blades and wheels; least expensive and lightest to transport, requires some effort to wield; not the best for all situations
- Motorized push mower: Uses gas, battery, or electric plug to run its motorized blades; still requires your pushing power to move the mower; requires less strength than a reel mower; a better option than a reel mower for larger, uneven lawns
Require less body strength and effort
Best for large lawns and uneven surfaces
Feels like less of a chore
Requires gas or electric energy source
Lighter in weight
Motorized types still need power
Reel types require more strength and energy
Reel types are safest; no mechanized parts
Reel types are most eco-friendly option
Parts of a Self-Propelled Lawn Mower
A self-propelled mower uses many parts in the mower's drive and transmission system, including engine parts, blades, pulleys, belts, a power source, and the safety bail. Much like a car, these parts need regular maintenance and occasionally replacement. The list goes on, from bearings and bushings to axles and air filters. These mowers can offer speed controls, height adjustments, discharge bag attachments, and even cup holders.
Some higher-end models may have a special feature like a blade override system that makes the blade stops spinning when you release the bar, and the unit stops moving, but it does not entirely shut off. This feature is convenient for two reasons: You can move the mower from point A to point B using its drive but not cutting grass along the way, and you don't have to restart the mower every time you release the bar.
The bail or squeeze bar safety feature is the norm nowadays, even on mowers that are not self-propelled, like a battery-powered push mower.
This safety feature works great to prevent accidents and avoid hazards in your line of sight, like giant holes on the lawn or sprinklers, rocks or boulders, children running around, or pet mishaps. If you slip and lose your footing, there's less chance of spinning blades coming into contact with your body. Also, while sidestepping things in the way, you don't have to fiddle with a switch to try to shut the mower off; you only release the bar.
How to Use a Self-Propelled Lawn Mower
- If using a clippings bag, check that the bag is empty.
- If your model uses gas, check the tank is filled and ready to go. If it has a gas primer, press the bulb until it's hard, priming the engine. If electric, plug in or attach a charged battery pack.
- Roll the mower to part of the lawn where you want to start.
- Adjust the cutter deck height to the highest height to ensure the blades don't get caught on the grass.
- Put the throttle in the start position and engage the choke if you have it.
- Grasp the engine's safety cutout bar with one hand and pull the starter cord with the other. Pull until you feel pressure, then give it a sharp tug to start the motor. You might need to repeat this a few times until it works.
- Set the throttle on the low position, disengage the choke, and set the cutter to the correct height.
- Use the squeeze bar to set the wheels in motion.
- Adjust your height and speed settings as you go.
Buying vs. Renting
You can get a decent self-propelled lawn mower starting at about $300. The price goes up from there. If you rent a lawn mower, it can cost you around $40 a day or $150 a week for a name-brand lawn mower that is listed for $450. Most lawn mowers will last many years and most good models come with a 2- to 4-year warranty. If you have any size lawn—whether small or large—it will require mowing. And, during the growing season, from spring to fall, you might need to mow it once or twice a week.
Rentals only work in your favor if you're saving money to get a new machine, your mower is being serviced, or you want to try a newer model before buying it. Ultimately, purchasing the device is less expensive than renting it.
Keeping the Self-Propelled Lawn Mower Maintained
Your lawn mower will need a tune-up once a year. You can do this maintenance or call for a service to maintain your machine. Annual maintenance includes changing the engine oil, adding a fuel stabilizer to the fuel system or removing the gas from the system if it's old or at the end of the season; replacing the spark plug and air filter; sharpening and balancing the mower blades; cleaning the housing; and winterizing your engine. Also, check your belts for wear and tear.
When to Replace Your Self-Propelled Lawn Mower
Most lawn mowers have replaceable parts that can help you extend the life of your machine. Do the required maintenance, such as changing air filters and getting new gas and oil. But, as the years wear on, your costs to fix a problem may be more than buying a new one.
If your machine chugs, sputters, or makes a loud unexplainable noise, the rule of thumb is the costs of repair should not come close to buying a new model. If the motor, transmission, or crankshaft is gone on your machine, it's probably time to look for a new lawn mower.