Storing your lawn mower outside doesn’t have to mean it will rust or break down early. With the right preparation and storage techniques, you can extend its life and keep it running smoothly year after year. This guide walks you through every step—from cleaning to fuel treatment—so your mower stays in top shape no matter the season.
Storing a lawn mower outside is common for many homeowners who don’t have garages or basements. But leaving your mower exposed to rain, snow, extreme temperatures, and critters can lead to costly repairs or premature failure. The good news? With proper preparation and smart storage practices, you can keep your lawn mower outside safely without sacrificing performance.
In this complete how-to guide, you’ll learn exactly how to prepare, store, and maintain your lawn mower so it survives the elements and starts up like new when spring arrives. Whether you’ve got a push mower, riding mower, or electric model, these steps apply to most gas-powered equipment.
Key Takeaways
- Clean Thoroughly Before Storage: Remove grass clippings, dirt, and debris from the deck, undercarriage, and engine to prevent rust and corrosion.
- Drain or Stabilize Fuel: Use fuel stabilizer for short-term outdoor storage or drain the tank completely for long-term use to avoid gum buildup.
- Store in a Dry, Covered Area: Even if outdoors, protect your mower from rain, snow, and direct sunlight using a tarp or storage shed.
- Lubricate Moving Parts: Apply oil to wheels, axles, and other metal components to prevent rust during cold months.
- Use a Breathable Lawn Mower Cover: Avoid plastic covers that trap moisture; opt for mesh or breathable fabric instead.
- Elevate the Mower: Lift the mower off the ground using blocks or a dolly to prevent flat spots on tires and improve airflow underneath.
- Check Monthly During Storage: Inspect for pests, moisture, or fuel degradation to catch issues before they become serious.
Why Proper Outdoor Storage Matters
When left untreated, outdoor exposure causes multiple problems:
– Rust forms quickly on metal parts like the undercarriage and blades.
– Fuel degradation happens within 30 days if not stabilized or drained.
– Moisture buildup inside the engine compartment leads to corrosion.
– Pests like mice may nest inside the mower deck or around the carburetor.
– UV damage weakens plastic parts such as the control panel or fuel cap.
By taking time now to store your mower correctly, you save money on repairs later and ensure reliable performance each season.
Step 1: Clean Your Lawn Mower Completely
Before anything else, give your mower a full wash. Grass buildup holds moisture and creates ideal conditions for rust.
How to clean effectively:
– Turn off the engine and disconnect spark plug wire for safety.
– Use a garden hose (or pressure washer on low setting) to blast away dirt from the deck and wheels.
– Scrub stubborn residue with a stiff brush and mild detergent.
– Pay special attention to the underside of the mower deck—this area traps the most debris.
– Wipe dry with a clean cloth or let air-dry completely.
Pro tip: If your mower has a mulching kit or bag attachment, remove and clean those separately too.
Step 2: Change the Oil and Filter (If Applicable)
Old oil contains contaminants that accelerate internal wear. For gas-powered mowers, changing the oil before storage helps protect the engine.
What to do:
– Run the engine briefly to warm up the oil (makes draining easier).
– Place a drain pan beneath the oil drain plug.
– Remove the plug and allow old oil to flow out completely.
– Replace the oil filter if your model has one (see our guide on how to change oil on Craftsman self-propelled mowers for detailed instructions).
– Refill with fresh oil according to your owner’s manual specifications.
Note: Electric mowers don’t require oil changes, but still benefit from cleaning and drying.
Step 3: Treat or Drain the Fuel System
Gasoline goes bad fast—especially when stored improperly. Ethanol-blended fuels can separate and form gummy deposits in the carburetor.
Option A: Use Fuel Stabilizer (For Short-Term Outdoor Storage)
– Fill the fuel tank completely.
– Add a high-quality fuel stabilizer (like Sta-Bil) as directed on the label.
– Run the engine for 5–10 minutes to circulate treated fuel through the system.
– This prevents fuel breakdown for up to 12 months.
Option B: Drain the Tank (For Long-Term Storage Over 6 Months)
– Disconnect the fuel line(s) and drain all gasoline into a safe container.
– Run the engine until it stalls (this clears leftover fuel from the carburetor).
– Consider adding a few drops of non-detergent 3-in-1 oil into the carburetor throat to coat internal passages.
Important: Never store a partially full tank—airspace allows oxidation.
Step 4: Lubricate All Moving Parts
Metal-on-metal contact causes friction and rust over time. Applying light machine oil protects critical components.
Parts to lubricate:
– Wheel axles and bearings
– Blade spindle shafts
– Height adjustment levers
– Throttle and choke linkages
Spray lubricant onto each moving part, then work them back and forth to distribute evenly. Wipe away excess so it doesn’t attract dust.
Step 5: Prepare the Battery (For Riding Mowers)
If your mower has a battery, take these steps:
– Disconnect the negative terminal first to prevent accidental sparks.
– Remove the battery and store it in a cool, dry place away from freezing temps.
– Charge it fully before storage and check monthly—lead-acid batteries lose charge slowly.
– Alternatively, use a trickle charger to maintain optimal voltage.
Tip: Some mowers allow you to leave the battery connected but isolate it with an inline fuse for convenience.
Step 6: Choose the Right Storage Location
Even though we’re talking about outdoor storage, location matters.
Ideal conditions include:
– Sheltered area like a carport, covered patio, or under a tarp
– Level surface to prevent fluid leaks or tire deformation
– Away from direct sun—heat accelerates rubber and plastic aging
– Elevated slightly above ground level to avoid pooling water
Avoid storing directly against walls where condensation builds overnight.
Step 7: Elevate and Cover the Mower
Placing your mower on wooden blocks or a lawn mower dolly keeps tires from developing flat spots and improves air circulation.
Covering tips:
– Use a breathable lawn mower cover made of mesh or canvas—not plastic bags or tarps that trap moisture.
– Ensure the cover fits snugly and doesn’t drag on the ground.
– Secure it with bungee cords or straps to prevent wind damage.
Avoid covering while wet—always ensure the mower is bone-dry first.
Step 8: Perform Monthly Checks During Storage
Don’t just set it and forget it. Every month, do a quick inspection:
– Look for signs of mold, rust, or insect activity.
– Shake the mower gently—listen for loose parts.
– If using fuel stabilizer, verify no stale smell remains near the carburetor.
– Recharge the battery if needed.
These small efforts prevent big headaches come spring.
Troubleshooting Common Outdoor Storage Problems
Even with best practices, issues can arise.
Mower won’t start after storage?
Chances are clogged carburetor jets or stale fuel. Try cleaning the carburetor (our guide on how to clean a Briggs and Stratton carburetor explains the process). If that fails, replace the fuel filter and check the spark plug.
Wheels feel stiff or flat?
Tires may have lost pressure or developed flat spots from sitting too long. Inflate to recommended PSI and rotate occasionally if possible.
Mice nested inside?
Seal openings with steel wool or hardware cloth. Trim nearby vegetation so rodents can’t jump aboard.
Cover blew off in the wind?
Upgrade to a heavier-duty model with elastic hems and weighted bottoms.
By addressing these issues early, your mower returns to service quickly and reliably.
Conclusion: Keep Your Mower Ready Year-Round
Storing your lawn mower outside doesn’t have to be stressful. With thorough cleaning, proper fuel treatment, strategic placement, and regular checks, your mower will stay protected through winter and beyond. These steps preserve not only mechanical integrity but also resale value and peace of mind.
Remember: prevention beats repair every time. Spend 2–3 hours preparing your mower today, and you’ll save hours of frustration tomorrow. When summer rolls around and the grass starts growing again, your mower will fire up instantly—ready to tackle that overgrown yard like a champ.
For more maintenance guides, check out our articles on sharpening lawn mower blades and adjusting belt tension on Husqvarna models.