Need To Replace Your Lawn Mower Engine? Here's How Much One Might Cost

• Technology

If you've performed all the necessary steps to maintain your lawnmower, there's a good chance the engine will outlast the rest of the mower. However, like all things mechanical, there is the possibility that your lawn mower engine will suffer a catastrophic failure. While it might be tempting to scrap the entire mower, if the rest of the mower is in decent shape, replacing the engine is a viable option.

Unless you plan to drop it off at a repair shop, you'll need to know a little about your lawn mower engine before proceeding. Small engines use either vertical or horizontal crankshaft configurations. Vertical shaft engines are more commonly used for lawn mowers, but some lawn and garden tractors employ horizontal shaft engines. It's also helpful to know the make, model, and serial numbers of both the lawn mower and the engine.

While there are several unexpected uses for old lawn mower engines, replacing a blown mower engine is an often overlooked way to recycle used lawn mower engines. Sometimes, old mowers with broken wheels, bent blades, or dead batteries can be found for free or just a few bucks. While the engines powering them aren't new, as long as they're not damaged, they can be rebuilt. In some cases, these salvaged engines can go directly into service, providing power for years to come. If you don't want the hassle of finding and swapping a salvaged lawn mower engine, there are new replacement engines available. This option will cost more, but it provides a factory fit, comes with a warranty, and has that new engine smell.

Briggs & Stratton replacement engines

The Briggs & Stratton name is synonymous with small engines in many households. With its headquarters in Wauwatosa, Wisconsin, and a worldwide manufacturing presence, U.S.-bound Briggs & Stratton engines are still made in America. The warranty period for Briggs & Stratton engines used by consumers ranges from 24 to 36 months, while commercial-use warranties range from 3 to 36 months.

The Briggs & Stratton website has a dedicated page for "Replacing your Engine?" If replacing an existing B&S engine, simply fill out the form provided. Replacing other engine brands requires selecting an appropriate B&S model and some careful measurements.

Vertical shaft B&S engines start at $249.13 with the 4.1-horsepower 104M02-0221-F1 Exi Series 7.25 GT. The 163cc B&S Exi 7.25 GT engine is used on push lawn mowers such as the 22-inch Toro Recycler Max and rebranded for use on other popular push mowers with similar specs.

The most expensive vertical shaft B&S engine is the 993cc Vanguard EFI with 40-horsepower priced at $5,376.04. While that sounds like a lot of money for a replacement lawn mower engine, they're typically used on commercial-grade equipment costing three times that amount, or more. One example is the Grasshopper Model 335B, a zero-turn lawn mower offering deck sizes up to 72 inches.

Kohler, rebranded as Rehlko, still makes lawn mower engines

If you didn't hear about what happened to Kohler engines, the energy business side of Kohler was renamed Rehlko to separate it from the company's houseware products in 2024. Although the letters in Kohler were mixed around to form the new name, Rehlko's engine offerings remain largely unchanged. For added peace of mind, Rehlko replacement engines come with warranty protection for up to three years in many cases.

Rehlko lists 42 engines across the professional landscape and lawn and garden categories. Of those, 18 models feature the vertical crankshaft orientation most often found on push-type and riding lawn mowers. The most powerful is the Command Pro EFI ECV980 with 38 horsepower. One of the smallest Rehlko lawn mower engines is the 173cc Command Pro CV173.

The Kohler ECV980 engine, list price $4,699.99, is available from Bad Boy Mowers for $4,299.99. At the lower end of the price spectrum, Arlington Power Equipment sells the Kohler CV173 for $428.96.

The Kohler/Rehlko ECV980 engine can be found on premium lawn mowers like the 72-inch deck Bad Boy Rogue with an MSRP of $15,930.00. Self-propelled walk-behind lawn mowers, like the $1,699.00 21-inch Variable Speed Toro, use Kohler's CV173 engine.

Kawasaki is a trusted name for lawn mower engines

Kawasaki makes a variety of engines used by several lawn mower brands for commercial and residential use. They are divided into seven different engine series, like the heavy-duty-commercial FX, residential FR, and lightweight FJ/FJ KAI.

One of the most popular for use on residential lawn mowers is the 23.0-horsepower Kawasaki FR691V engine. The Kawasaki Engine Store, an authorized Kawasaki Engines dealer, lists the price for the 726cc FR691V at $2,390.54, but it's sometimes on sale for $1,992.12.

The most powerful Kawasaki F-Series V-twin engine found on some lawn mowers is the FX1000V EFI with 38.5 horsepower. For comparison, Cutting Edge Lawn Equipment lists the price of the 999cc FX1000V at $3,799.00, but it's currently out of stock. The Gravely Pro-Turn 560 is one lawn mower example using the Kawasaki FX1000V EFI, available at Dublin Outdoor & Power Sports, among other retailers, for $17,099.00. Kawasaki FR and FX engines come with a 3-year warranty.

Among the smallest Kawasaki engines designed for use on push mowers are the 179cc FJ180V and the upgraded FJ180V KAI. Stafford Equipment sells the 6-hp FJ180V for $499.00. Commercial-grade push mowers like those from Bad Boy Mowers and Exmark feature Kawasaki FJ180V engines.

Replacement Honda lawn mower engines

Honda is another leading brand of small engines, but Honda recently discontinued a large swath of its lawn mower production. Up until that point in time, the company offered a number of options for vertical-shaft single-cylinder and V-twin lawn mower engine replacements.

Honda's lineup of replacement single-cylinder lawn mower engines included the GCV, intended for residential use, the commercial-grade GXV, and the GSV, designed for light commercial and residential use. V-twin replacement engine options included the GX, GXV, and iGXV models. If you're unsure of which Honda engine is right for your application, try out Honda's "Engine Quick Find" tool.

The Honda GCV engines come in two sizes, the 160cc GCV160 and 187cc GCV190. They, along with the GSV190, feature an overhead camshaft valve train. All other Honda replacement lawn mower engines feature the more conventional overhead valve design. The largest Honda V-twin lawn mower engine is the 779cc iGXV800.

Honda doesn't list prices for any of its lawn mower engines, but Northern Tool lists the Honda GXV160 for sale at $499.99 plus shipping (estimated at $21.49 to the centrally-located state of Oklahoma). The Honda engine ships directly from the factory and isn't available in any Northern Tool store we could find. The good news is that it comes with a 24-month manufacturer's warranty covering parts and labor.

Another option for finding a replacement Honda lawn mower engine is to search pre-owned sites, such as eBay and Facebook Marketplace. It's possible to find used Honda lawn mower engines for as little as $100.

Harbor Freight Predator engines

Harbor Freight's Predator 212 engine can replace a variety of horizontal-shaft small engines, but the discount tool retailer offers a vertical-shaft Predator model to replace your lawn mower engine, too.

The 6.5-hp Predator 212, priced at $149.99, is available in two versions, one with EPA certification and the other with CARB certification. The entire lineup of horizontal-shaft Predator engines ranges from the $119.99 3-hp model to the 670cc 22-hp V-twin priced at $949.99.

The only vertical-shaft Predator lawn mower engine is the 5.5-hp 173cc overhead-valve engine, priced at $229.99. It also comes with either EPA or CARB certification. It features a cast-iron cylinder and ball-bearing crankshaft supports among what Harbor Freight describes as "upgraded engineering and construction."

The 173cc Predator engine's product page lists it as a replacement for various Briggs & Stratton, Kohler, Kawasaki, and Honda lawn mower engines. The 5.5-hp Predator engine doesn't have the same brand recognition as other engines on this list. Perhaps even less confidence-inspiring, it comes with a basic, and limited, 90-day warranty guaranteeing the engine "will be free from defects in materials and workmanship."