Winterising Outdoor Power Equipment This Autumn: Mower, Chainsaw, Batteries and Tractor

To winterise garden machinery, deal with the fuel first: petrol left in a small engine over winter causes, by L'Atelier's count, 90% of mowers that will not start in spring. Then store cordless batteries part-charged (around 40-60%) indoors, and give the tractor a full tank, a protected battery and antifreeze strong enough for your area. The guide below follows the autumn calendar, from the last cut to the tractor going into the shed.

Step one: the last cut of the year

The final mow sets the lawn up for winter. L'Atelier recommends 4-5 cm, one notch shorter than your summer setting, once growth has slowed (it says this is often late October to November depending on region) and on a dry day. Too short and roots are exposed to frost and moss moves in; too long and the grass lies flat under snow and damp, then rots.

• Clean under the deck straight away: packed grass holds moisture and rusts the deck and blade.
• Check the blade. Whitish, torn tips the day after mowing mean it needs sharpening: lead off the spark plug first, keep the original angle, rebalance it.
• Check the oil level on petrol models before the winter oil change.

Winterising a petrol lawnmower in five steps

1. Fuel: empty or stabilise. Either run the engine until it stops, carburettor included (simple, no residue), or fill the tank, add stabiliser and run it for 5 minutes so the treated fuel reaches the carburettor.
2. Oil change. Old oil is acidic. Warm the engine first so it drains thoroughly.
3. Spark plug and cylinder. Remove the plug, check and clean it, pour a tablespoon of engine oil into the cylinder, pull the cord 2-3 times to coat the cylinder and rings, then refit the plug.
4. Air filter. Foam: wash and dry. Paper: blow it out. Replace if needed.
5. Blade and deck. Clean underneath and sharpen the blade.

Then store it in a dry place with the blade flat rather than on its edge; if the mower has an electric start, disconnect the battery and keep it somewhere warm. The guide is blunt about the one mistake to avoid: ordinary petrol left all winter with nothing added is the leading cause of gummed-up carburettors.

Hedge trimmer, strimmer and blower

Autumn is also when the hedge trimmer comes in after the final trim. L'Atelier's guide: clean sap and debris off the blades with a brush and resin cleaner, spray lubricant along the full length, check the blades for play, and store with the blade guard on in a dry place. Sharpen dull teeth with a flat file or stone at the original angle (usually 30-45°), bevelled face only. Battery models: remove the battery and store dry. Corded models: check the cable for cuts. Petrol models also get the 2-stroke treatment: drained or stabilised fuel.

For brush cutters, the starting-problems guide calls draining the tank and running the engine until it stalls the best prevention against 80% of starting problems, whenever the machine will stand more than 30 days. A petrol leaf blower follows the same 2-stroke logic: if possible, run it until the old mix is used up before storage.

Laying up a chainsaw

The complete guide triggers this routine for any lay-up over 30 days; the season-by-season guide for a 2-3 month break. Both are emphatic about not leaving mix in the tank all winter, since ethanol attacks carburettor membranes and fuel lines. When you bring it back out: correct chain tension, fresh mix only, a check of the chain brake and inertia sensor, then 2-3 minutes at idle before cutting.

Cordless batteries: part-charged, indoors

Lithium-ion packs dislike three things over winter: deep cold, being left flat and sitting at 100% for months. L'Atelier's winter storage guide gives the routine:

• Charge to about 50% (the ideal zone is around 40-60%) before storing. The platforms article gives a broader 40-80%, ideally 50-60%.
• Take the battery off the tool to stop constant micro-discharge.
• Bring packs indoors to a dry, temperate room rather than an uninsulated garage or shed that freezes. The platforms article puts the target at 10-25°C.
• Look at them once mid-winter and top up if the level has dropped noticeably.
• Never store a swollen or damaged pack: recycle it.
• In spring, charge fully before use; a pack that has lost a lot over winter is near the end of its life.

Tractor winterisation checklist

1. Cooling system first. Check antifreeze strength and condition: diluted coolant can freeze and crack the block or radiator. L'Atelier's coolant guide gives about -37°C for a 50/50 mix with demineralised water, about -52°C at 60/40, and never more than 60% antifreeze.
2. Battery. Disconnect it or fit a maintainer, store it charged somewhere temperate, clean the terminals. A flat battery that freezes is fit only for recycling.
3. Diesel. Fill the tank to limit condensation. In very cold areas, winter diesel prevents waxing. Purge the water separator.
4. Oil. Change it if due, so it winters on clean oil.
5. Grease every point (joints, lift linkage) to protect against corrosion, and check the hydraulic level and condition.
6. Tyres at the right pressure to avoid flat spots; take weight off them if you can.
7. Shelter. Dry and covered, or a breathable tarp; a rag in the exhaust and intake against rodents (remove it before starting). A thorough final clean removes corrosive residue.

In spring, L'Atelier's 20-point start-of-season checklist takes over: battery above 12.4 V, coolant protecting to at least -37°C, tyres typically down 0.2-0.4 bar, and a look for rodent damage on wiring and in the air filter.

Mistakes that undo the work

• Leaving ordinary petrol or 2-stroke mix in a small engine all winter with nothing added.
• Topping up a can of mix in November and using it in April.
• Leaving cordless packs on the charger, fully charged, or in a shed that freezes.
• Putting the chainsaw away with sawdust packed in the bar groove and cooling fins.
• Forgetting the rag in the tractor's exhaust or intake when starting it in spring.
• Cutting the lawn very short on the last mow: frost and moss follow.

And in spring, for the 2-stroke kit: L'Atelier's leaf blower guide gives the cold start routine after a long lay-up, choke closed, a few primer presses, pull, and open the choke as soon as it catches. Pulling fifteen times with the choke closed floods the engine.

If you want to check a value for your own machine, ask the L'Atelier power tools and garden machinery base. For example: "My petrol mower won't start this spring although it ran fine last autumn. What is the usual cause?"

Sources on la-telier.com: winterising a petrol mower, autumn hedge trimmer care, chainsaw maintenance guide, tractor winterisation.