Generators hate winter as much as we do—minus the hot cocoa. To winterise a generator, clean it, add fuel stabiliser, check the battery, and swap in cold-weather oil. Simple, right? But a few missed steps can leave you freezing. Keep reading to make sure your backup power doesn't back out.
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Winter can mess with your generator in sneaky ways. From fuel thickening to sticky starts, a bit of prep goes a long way. Whether you're up in the Blue Mountains or down in chilly Tassie, these steps will help your generator face winter without chucking a tantrum.
Let's start with fuel—the lifeblood of your generator. When it gets cold, fuel can break down or gum things up. And if your unit sits idle, that's when the trouble usually starts.
If you're putting the generator away for a bit, stabilise the fuel first. Add a fuel stabiliser to a full tank of fresh petrol. Then, run the generator for a few minutes to circulate it.
This helps stop varnish and sludge from building up while it sits in the shed.
If you won't be using the generator for a few months, draining the fuel tank is the safer bet. Old fuel can clog the carburettor and corrode metal parts. Use the drain screw or siphon method—just make sure you do it somewhere well-ventilated and away from open flames.
Your generator needs to be well-lubed to get through winter without groaning. Cold weather thickens oil, and that puts strain on your engine.
The trick here is using winter-grade oil—something like 5W-30 that flows better in low temps. Run the generator for a few minutes first so the old oil drains easier. Once topped up, your engine will thank you every time you turn the key on a frosty morning.
While you're under the hood, check the filters. A clogged air filter makes your generator work harder, especially in cold air. If it looks dirty or dusty, swap it out. Same goes for the fuel filter—clean filters mean smoother starts and fewer hiccups.

Now that the inside's sorted, let's protect the outside—and make sure the battery doesn't cop a winter meltdown.
A flat battery in summer is annoying. In winter? It could mean no power when you need it most.
Test the voltage before the cold weather kicks in. If it's low, charge it up or replace it altogether. A battery maintainer or trickle charger can keep it alive during long periods of inactivity.
In really cold regions, a battery warmer helps keep things at a workable temperature. Or just disconnect the battery and store it indoors—somewhere cool but not freezing. Either way, label the cables so you don't forget what goes where later.
Rain, frost, and nosy wildlife can all do damage if your generator isn't stored properly.
Get yourself a breathable, weatherproof cover—not a plastic tarp that'll trap condensation. If your generator's outdoors, consider a purpose-built enclosure that keeps it protected while allowing airflow.
Never box it in completely. Your generator still needs to breathe. Make sure there's clearance on all sides—especially the exhaust—and steer clear of placing it near sheds, windows or fences.
If you're serious about year-round reliability, a few winter add-ons won't go astray.
An engine block heater gently warms your generator's engine before startup. No more harsh cranking on icy mornings. They're ideal if you're in areas with regular frost or snow.
There are extras like oil warmers, heavy-duty power cords, and automatic choke kits. Not essential for everyone, but worth it if your generator sees frequent use in colder weather.

If your generator's going into hibernation, storage is more than just finding it a cosy corner.
A little prep now means fewer headaches later. Clean it, drain the fuel (or stabilise it), and store it properly.
Dry, well-ventilated, and off the floor is ideal. A garage or shed works best. Keep it away from fertilisers, salt, or anything else that might speed up corrosion.
Wipe down the metal parts with a bit of oil or corrosion spray. Check for any leaks and patch them before they turn nasty. And remember to cover it—but only with something breathable.
Just like a car, your generator needs a little run every now and then to stay in shape.
Start it once a month, even if you're not using it. Let it run with a small load for 15–20 minutes. This keeps the fluids moving and stops the battery from dying.
Listen for odd sounds, slow starts, or warning lights. Winter has a way of exposing weaknesses, so it's better to catch them early.
Even the best-prepped generator can throw a tantrum when it's cold. Be ready for the usual suspects.
Check the oil viscosity, spark plug, and battery voltage. Nine times out of ten, it's one of those. Cold engines are stubborn, so warm them up gently if you can.
Diesel can gel in freezing temps, blocking fuel lines. Use a winter blend or anti-gel additive. For petrol, stabiliser prevents moisture and keeps it from separating.
When the cold hits and the lights go out, the last thing you want is a generator that won't start.
So give it a clean. Swap the oil. Check the battery. Cover it up and take it for a spin every month.
With a bit of care, your generator will be ready to step up—no matter how cold it gets.