Your lawn mower is one of the most important tools you own for keeping your yard neat, healthy, and inviting. In fact, according to Statista, the global lawn mower market is forecasted to reach a value of more than $44 billion by 2027. While regular maintenance helps extend its lifespan, every mower eventually shows signs of trouble. Knowing when to seek professional repair can save you time, money, and frustration, while also preventing small issues from becoming major breakdowns. Here are nine signs it’s time to call in a professional for lawn mower repair.

1. The Engine Struggles to Start

One of the most common frustrations for homeowners is a mower that refuses to start. When the engine struggles, many assume the issue is something simple like stale fuel or a dirty filter. While those can be causes, repeated difficulty starting the mower often points to deeper problems. The carburetor might not be mixing air and fuel correctly, or the ignition coil could be failing. Even a faulty starter mechanism can create the impression of an engine that simply won’t cooperate.

When you continually pull the starter cord or turn the key multiple times, you’re placing additional stress on components that are already struggling. Over time, this can damage the recoil starter, wear down spark plugs, or even flood the engine. A lawn mower repair professional can diagnose whether the problem is electrical, mechanical, or fuel-related and apply the right fix the first time. This prevents you from wasting energy and ensures the mower runs reliably when you need it most.

2. The Mower Stalls While Running

Few things are more irritating than getting the mower started only to have it stall halfway through the job. Stalling typically occurs when the engine isn’t getting enough fuel, air, or spark. Blocked fuel lines, restricted carburetor jets, or clogged air filters are all potential culprits. Sometimes, the mower will run for a few minutes before stalling, which may indicate that debris is shifting in the tank or that the fuel pump is malfunctioning.

While occasional stalling might be solved with a quick cleaning, repeated stalling signals an underlying mechanical issue. Continuing to mow without addressing the problem risks damaging the engine. Professionals have tools to measure fuel pressure, test spark delivery, and confirm air intake, helping them identify exactly where the breakdown occurs. With a technician’s help, your mower can operate consistently and finish the job without interruptions.

3. Uneven or Ragged Cuts

The primary purpose of a mower is to deliver a clean, uniform cut. When you start noticing ragged patches, uneven height, or scalped areas where the mower seems to dig too deeply, something is off. Dull blades are often the first thing to check, but they aren’t always the only reason. A mower deck that has become unbalanced or a bent spindle can make the blade strike at the wrong angle, resulting in a poor-quality cut.

An uneven lawn not only looks unattractive but also stresses the grass, making it more vulnerable to disease and pests. A lawn mower repair professional can check blade alignment, level the deck, and replace worn bearings or bent parts. These adjustments restore the mower’s ability to deliver a smooth, professional finish. Over time, consistent cutting at the correct height keeps your lawn healthier and reduces the risk of brown spots or uneven growth.

4. Strange Noises or Vibrations

If your mower suddenly begins making unfamiliar noises—grinding, knocking, squealing, or rattling—it’s a sure sign that something is wrong. Excessive vibration often occurs when blades are bent, unbalanced, or installed incorrectly. Loose bolts in the deck or worn engine mounts can also create shaking that rattles the entire machine. Ignoring these symptoms risks serious damage, as vibrating parts can loosen further and cause chain reactions throughout the mower.

A lawn mower repair technician can carefully inspect the machine for bent blades, broken bearings, or misaligned pulleys. By tightening hardware, balancing blades, or replacing worn parts, they can restore the mower’s quiet, steady performance. Taking action at the first sound of trouble can prevent larger, more expensive failures in the engine or transmission down the line.

5. Oil Leaks or Excessive Smoke

Few things raise concern faster than seeing oil stains on the driveway after parking your mower. Leaks may develop from damaged gaskets, cracked casings, or worn seals that no longer hold fluids properly. Even a small leak can quickly lead to low oil levels, which in turn starve the engine of lubrication and cause internal parts to wear prematurely.

Excessive smoke is equally troubling. Blue smoke often indicates that oil is burning inside the combustion chamber, while black smoke usually means the fuel mixture is too rich. White smoke can suggest water contamination or a blown gasket. Each of these issues requires different repairs, many of which involve opening the engine—something best left to professionals. A technician can determine the cause of the leak or smoke and perform the necessary repair to prevent further damage and restore safe operation.

6. Self-Propelled Features Stop Working

Self-propelled mowers are designed to make mowing less physically demanding. If you suddenly find yourself pushing harder than usual, it’s often because the drive system has worn down. A loose or broken drive belt is a common issue, but problems with the transmission, gears, or pulley system can also cause the wheels to stop engaging properly.

Trying to replace these parts at home can be challenging, especially since many drive systems are enclosed in protective housings. A lawn mower repair professional can disassemble the system, inspect for wear, and install replacement parts correctly. With expert repair, the mower regains its self-propelled function, sparing you the exhaustion of pushing a heavy machine across the yard.

7. Fuel Efficiency Drops

If your mower seems to burn through fuel faster than it used to, it’s a sign of declining efficiency. A dirty carburetor, clogged fuel injectors, or worn spark plugs can all reduce how effectively fuel is converted into energy. Running a mower in this condition not only costs more in gasoline but also strains the engine, potentially shortening its lifespan.

Lawn mower repair technicians can clean or rebuild carburetors, replace filters, and adjust fuel mixtures to restore optimal efficiency. This not only lowers fuel costs but also improves performance, ensuring that the mower runs smoothly and reliably. Regular maintenance paired with professional service can keep fuel use steady, even as your mower ages.

8. Difficulty Adjusting Cutting Height

Being able to adjust cutting height is important for lawn health. Grass cut too short can burn in hot weather, while grass left too long may become susceptible to disease. If the mower’s adjustment lever becomes stiff, stuck, or fails to respond, it compromises your control over the lawn’s condition. Corrosion, broken linkages, or worn parts inside the deck are often to blame.

Lawn mower repair professionals can lubricate moving components, replace broken hardware, and restore smooth function to the adjustment system. By doing so, they make it easy for you to adapt mowing height to seasonal conditions and the type of grass in your yard. Restoring this function helps you maintain the flexibility needed to keep your lawn healthy year-round.

9. The Mower Emits Unusual Smells

Unusual smells should never be ignored. A burning odor could mean that a drive belt is slipping, an electrical connection is overheating, or grass clippings have clogged the engine housing. Strong gasoline smells often point to leaking fuel lines or carburetor issues. Ignoring these odors is not only inconvenient but potentially dangerous, since fuel leaks and overheated components can create fire hazards.

Professional lawn mower repair technicians can locate the exact source of the smell and take corrective action. Whether it’s replacing a leaking fuel hose, tightening an electrical connection, or cleaning a clogged housing, they ensure that your mower is safe to operate. Taking action early reduces the risk of serious accidents and helps keep the mower dependable.

Your lawn mower is an essential part of maintaining a beautiful outdoor space. Recognizing the early warning signs of trouble can save you from costly breakdowns and wasted effort. If you're located in the Oakland, TN area, contact our team at Lewis Small Engines LLC today to schedule an appointment!