Quick verdict
A 21-inch steel-deck gas mower with a 170cc OHV four-stroke engine, auto choke, recoil start and rear-wheel self-propelled drive, with a 3-in-1 deck and six heights from 1.5 to 3.9 inches. It suits a half-acre or larger lawn with slopes where battery runtime is a worry. The caveat is a budget brand with no stated engine maker, drive speed or bag size.
Strengths
- 170cc OHV four-stroke with auto choke and recoil start
- Rear-wheel self-propelled drive for slopes and a full bag
- 21-inch steel deck with mulch, side discharge and rear bag
- Six heights from 1.5 to 3.9 inches on dual levers
- Handle folds for storage
Weaknesses
- Engine maker and drive speed are not stated
- Bag capacity, weight and warranty are not given in the listing
- Dual-lever height adjustment is slower than a single lever
- Gas mower upkeep: oil, plug, filter and stabilized fuel
The overall YardToolLab Score is out of 100. Section scores are out of 10.
Who this mower is for
There are still lawns where gas makes sense: half an acre or more, slopes, thick southern grass and no appetite for a second battery. The PowerSmart 21-inch 170cc self-propelled mower is the budget route into that class. It has the parts that matter, a 170cc OHV engine, rear-wheel drive, a steel deck and three discharge modes, from a brand that sells through Amazon and the big-box stores rather than through a dealer.
This review is based on the maker’s published specifications and on recurring owner feedback. We have not run this product ourselves.
What you get
The box holds the mower, with the handle folded, and a manual. The engine is a 170cc OHV four-stroke with auto choke and a recoil pull start. The drive is rear-wheel self-propelled. The deck is 21-inch steel and offers mulching, side discharge and rear bagging. Cutting height runs from 1.5 to 3.9 inches in six positions, set by two levers, one per axle. The listing does not name the engine maker, state the drive speed, give the bag capacity or weight, say whether oil is included, or quote a warranty term. Check the product page for those before you order.
Engine and cutting
A 170cc overhead-valve engine is the common size for a 21-inch self-propelled deck, and it has the torque to keep blade speed up in thick or damp grass where a 140cc engine struggles. PowerSmart’s claim that it cuts through thick or wet grass efficiently is fair for the displacement. Auto choke removes the primer bulb and choke lever, so starting is a matter of pulling the cord, and owners of PowerSmart gas mowers generally report that they start on the first or second pull when the oil is fresh and the gas is not stale. The steel deck gives the airflow for a good bag fill and a clean mulch in weekly growth.
Drive and traction
Rear-wheel drive is the right layout for a self-propelled mower. The weight of the engine and a full bag sits over the driven wheels, so it keeps pulling on a slope where front-drive mowers spin. The listing does not say whether the speed is fixed or adjustable; most budget gas mowers are single speed at a comfortable walk, and if you need to crawl on a steep bank or hurry on the flat you should confirm the drive type before buying. The drive bail is at the handle alongside the engine bail in the usual arrangement.
Build, handling and ergonomics
A 21-inch steel-deck gas mower is heavy, typically in the 70 to 90 pound range for the class, and PowerSmart does not state a figure. That weight is what gives rear-wheel drive its traction, and it is why the drive matters so much. The dual-lever height adjustment is a slower system than a single lever, since you set the front and rear separately, though it is also simpler and less likely to work loose. The handle folds for storage. A recurring complaint across budget gas mowers is handle flex and hardware that needs snugging after the first few cuts.
Living with it
Gas ownership is a routine: fill the oil before the first start and check it every few cuts, change it each season, replace the plug and air filter yearly, sharpen the blade twice a season, and run the tank down or stabilize the fuel before winter. Ethanol-free fuel helps a small engine that sits for months. The warranty term is not in the listing; PowerSmart typically backs its gas mowers for a fixed period, so confirm the term and the service route, which for this brand is usually by phone or email rather than a local shop.
Alternatives to Consider
The Craftsman M215 21-inch 159cc front-wheel-drive mower is the mainstream budget rival with Lowe’s service behind it. The Toro Recycler 22-inch SmartStow with rear-wheel drive costs more and brings a bigger dealer network and a better bagging system. If the lawn is under half an acre and flat, the PowerSmart 80V 21-inch push mower removes the gas upkeep altogether.
Verdict
Buy the PowerSmart 21-inch 170cc self-propelled mower if you have a half-acre or larger lawn with slopes, want rear-wheel drive and a steel 3-in-1 deck, and are willing to do basic engine upkeep to keep the cost down. Skip it if you want a named engine, variable speed, a local dealer, or a quieter cut on a smaller lawn where battery now does the job.
Full specifications
PowerSmart 21-Inch 170cc Self-Propelled Gas Lawn Mower, 4-Stroke OHV Engine, Rear-Wheel Drive, Steel Deck FAQs
The listing describes rear-wheel self-propelled drive but does not say whether the speed is fixed or variable. Budget gas mowers in this class are most often single speed; confirm on the product page if it matters.
The listing does not say. Most new gas mowers ship either dry or with a small starter bottle. Buy a quart of the grade named in the manual and fill before the first start, because running dry ends the engine.
PowerSmart does not name the engine maker in the listing. It is described as a 170cc OHV four-stroke with auto choke, a common size for a 21-inch deck from several makers.
PowerSmart claims the engine cuts through thick or wet grass efficiently. A 170cc engine on a 21-inch steel deck typically copes with damp growth on the side discharge setting; mulching wet grass clumps on any mower.
