My generator won't start after sitting all year
It's the fuel, roughly nine times in ten. Modern petrol with ethanol in it goes bad in months and leaves varnish in the carburettor jets, which are the width of a pin.
What actually works
Thirty minutes with something real plugged in. This single habit prevents nearly every problem on this page — and it's also the only way to find out the generator *can't* carry your load before the night you need it.
Stabiliser in every can, rotate the stock, and either run the carburettor dry before storage or shut off the fuel tap and let it stall. Ethanol-free petrol if you can get it.
When it has already happened, this is the fix: pull the bowl, clean the main jet. It's an hour and a $10 gasket kit, and it is the most common small-engine repair there is.
The habit worth building. An unloaded generator shows perfect voltage right up until it can't carry anything.
It'll fire once and tells you nothing about why it wouldn't. Used repeatedly it washes the oil off the cylinder walls.
Run the numbers
- Generator sizing & fuel burn → — free calculator, works offline.
Also searched as
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