Mower Winter Storage: Fuel, Blades, Battery

Every November, the golf course shop turned into an assembly line. Every mower, every blower, every utility vehicle came through, got serviced, and got parked for winter. In spring they all started. At home, most mower problems in April are caused by how they were put away in October. Here's the routine, scaled down to a garage.

1. Deal with the fuel

Old gas is the number one reason mowers don't start in spring. Gasoline breaks down in storage, and ethanol blends absorb water. Over a winter, that turns into varnish and gum that clogs the carburetor's tiny passages.

Two good options:

• Stabilize it. Add fuel stabilizer to a fresh tank of gas, then run the engine for five to ten minutes so the treated fuel reaches the carburetor.
• Run it dry. Run the mower until it stops, so there's no fuel left to go bad. Some manufacturers recommend this; others say stabilizer is better because a dry tank can rust or let seals dry out. Check your owner's manual.

If you can find ethanol-free gas, it stores much better.

2. Change the oil

Used oil holds acids and combustion byproducts that sit on engine parts all winter. Change it in fall, with the engine warm so the oil drains easily. Use the type and amount in your manual.

3. Disconnect the spark plug

Before you touch the blade or tip the mower, pull the spark plug wire off the plug. That keeps the engine from accidentally starting. While it's off, check the plug. If it's fouled or worn, replace it now so you're ready for spring.

4. Clean the deck

Wet grass clippings packed under the deck hold moisture all winter and rust the deck through. Tip the mower with the air filter and carburetor side up (check your manual) and scrape out the clippings. A plastic putty knife works well. Some mowers have a washout port you can hook a hose to.

5. Sharpen or replace the blade

A dull blade tears grass instead of cutting it, and torn tips turn brown and invite disease. Take the blade off, sharpen it, and balance it, or swap in a new one. Doing it now means you're not scrambling in spring.

6. Air filter

Clean or replace it. A clogged filter makes the engine run rich and hard to start.

7. Battery

For riding mowers and electric-start push mowers:

• Take the battery out (or disconnect it) and store it somewhere it won't freeze.
• Put it on a battery maintainer (a trickle charger made for long-term storage), not a regular charger.

For battery-powered mowers, follow the manufacturer's storage advice. Most say to store the battery partly charged, indoors, not in a cold garage.

8. Tires and grease

Check tire pressure on riding mowers; low tires can flat-spot over winter. Grease any fittings while you're at it.

9. Store it right

• Somewhere dry, out of the weather.
• Covered loosely, not with a tarp tight enough to trap moisture.
• Away from a furnace, water heater, or anything with a pilot light if there's any fuel in it.

In spring

Reconnect the spark plug, check the oil level, fill with fresh gas, and you should be mowing on the first or second pull.

Ten minutes of work in fall saves you a trip to the repair shop in spring, and the shops are backed up for weeks once the first warm weekend hits.

If your mower is done for the year, check when to stop mowing for the season to make sure the last cut was the right height.

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