It’s one of the most common questions homeowners ask. The honest answer is: it depends. But there’s a clear framework for thinking it through, and most of the time, the math lands firmly in favour of repair.
How Long Should a Lawn Mower Actually Last?
The takeaway: if your mower is under eight years old and has been reasonably well looked after, the odds are good there’s plenty of life left. A repair is almost always the smarter financial move.
The 50% Rule: A Simple Way to Think About Repair Costs
- A new walk-behind gas mower runs roughly $400 to $800 CAD for a quality residential model. That puts your repair threshold at around $200 to $400.
- A new riding mower or lawn tractor typically costs $3,000 to $5,000+. Under the 50% rule, repairs up to $1,500 or more can still be cost-justified.
The 50% rule breaks down when the mower is already at the far end of its lifespan, or when you’re facing a major engine or crankshaft failure on an older, lower-quality machine. That’s when replacement starts making more sense.
Repairs That Are Almost Always Worth It
These are the repairs where the math is clear. The cost is low, the impact is real, and skipping them often turns a small problem into a much bigger one.
Spark plug replacement: One of the most overlooked causes of a mower that won’t start or runs poorly. Spark plugs should be replaced roughly every 100 hours of operation. The part typically costs under $10, and the job takes minutes. If your mower is struggling to start, this is the first thing to check.
Air filter cleaning or replacement: A clogged air filter starves the engine of oxygen and causes it to run rich, smoke, and lose power. Cleaning or replacing the filter is a low-cost fix that can dramatically restore performance.
Carburetor cleaning: Old fuel left sitting over the off-season is the leading cause of starting problems in Ottawa. Ethanol in modern gasoline breaks down quickly and leaves behind a varnish that gums up the carburetor. A carb clean or rebuild is typically a moderate-cost repair that brings mowers back from the dead.
Belt replacement: Drive belts and blade belts wear out over time. A slipping or broken belt is usually straightforward to diagnose and replace, and it’s far cheaper than a new machine.
Blade sharpening: Dull blades don’t just cut grass poorly. They tear it, which stresses the lawn and makes the engine work harder. Annual blade sharpening is one of the best investments you can make in a mower’s longevity.
Oil change and tune-up: Running an engine on degraded oil dramatically shortens its life. A full tune-up, including fresh oil, a new spark plug, a clean air filter, and fresh fuel, can restore performance and add years to a mower that feels tired.
Repairs That Deserve a Harder Look
In these cases, the most useful thing you can do is get an honest upfront assessment from a technician who will tell you the truth rather than just take the job.
The Hidden Cost Most People Forget: The Price of a Replacement
Compare that to a $150 to $300 repair that gets another three to five seasons out of a machine you already know, one that may have been serviced and upgraded over the years, and the math becomes clear pretty quickly.
When Replacing Actually Makes Sense
- The mower is more than 10 to 12 years old and has accumulated significant hours
- You’re facing repeated repairs; if the same machine has needed major work two or three seasons in a row, it may be telling you something
- The repair cost exceeds 50% of replacement value on a machine that’s already well past its prime
- There is significant rust, structural damage, or deck failure that compromises safety or cut quality
- You’re upgrading your property and a larger lawn, different terrain, or changed needs make a new machine the practical choice regardless of the old one’s condition
Even in these cases, it’s worth getting a professional opinion first. What looks like a dying mower is sometimes a machine that needs a carburetor clean and a fresh set of blades.
The Best Way to Avoid the Repair-or-Replace Dilemma Entirely
Annual maintenance eliminates most of that. It’s not a luxury. It’s the most cost-effective thing you can do for a machine that costs hundreds to thousands of dollars to replace.
How Legacy Small Engines Can Help
We also offer annual lawn mower service subscriptions starting at $175/year, which include a full inspection, oil and fluid service, spark plug replacement, blade sharpening, deck cleaning, and pick-up and delivery. *(Pricing may vary depending on the repair. Contact us for a free upfront estimate.)*
Ready to Find Out If Your Mower Is Worth Fixing?
You don’t need to make the repair-or-replace decision on your own. Bring it in, or let us come to you, and we’ll give you a straight answer along with a clear upfront estimate.
Here’s how it works:
- Schedule a pick-up. We offer flat-rate pick-up and delivery across our service area, from Stittsville and Kanata to Nepean and beyond. No truck required. Check the pricing page for pick-up rates.
- Choose the service that fits. A one-off repair if it’s a single issue, or an annual subscription plan starting at $175/year if you want the mower looked after every season. Subscription customers also get 10% off parts and accessories.
- Book in minutes. Call 613-899-4809 or fill out the form on the Legacy Small Engines contact page. Let us know the make and model, what it’s doing (or not doing), and a convenient pick-up time.
Frequently Asked Questions
How do I know if my lawn mower is worth repairing?
Start with the 50% rule: if the repair costs less than half the price of a comparable new mower, it’s almost always worth fixing. Also consider the machine’s age and history. A well-maintained mower under ten years old with a single repair need is usually a strong candidate for service rather than replacement.
What is the average lifespan of a walk-behind lawn mower?
A budget walk-behind mower is typically rated for around 450 to 500 hours of use, while a quality residential model can last 1,000 to 1,500 hours. In practical terms, that’s anywhere from 8 to 15-plus years depending on how well the machine has been maintained.
What are the most common reasons a lawn mower won’t start?
The most frequent causes are a fouled spark plug, a clogged carburetor from old fuel, a dirty air filter, or stale gasoline left in the tank over winter. Most of these are inexpensive to fix and are among the first things a technician will check.
How much does it typically cost to repair a lawn mower in Ottawa?
Most common repairs, including carburetor cleaning, spark plug replacement, belt replacement, and blade service, fall in the $50 to $200 range. More involved work like an engine rebuild or drivetrain repair will cost more. *(Pricing varies by job. Contact Legacy Small Engines for a free upfront estimate.)*
Is it cheaper to repair a lawn mower or buy a new one?
In most cases, repair is the more cost-effective choice, especially if the mower is under ten years old. A new quality walk-behind mower costs $600 to $1,000+ CAD, and a riding mower runs $3,000 to $5,500+ CAD. A well-timed repair for a fraction of that cost can add several more seasons to a machine you already own.
How can I make my lawn mower last longer?
Annual servicing is the single biggest factor. Changing the oil, replacing the spark plug, cleaning or replacing the air filter, sharpening the blade, and running the tank dry before storage will dramatically extend the life of any mower. Ottawa’s long winters make pre-season and post-season maintenance especially important.