What to Ask Before Buying a Used Generator
The real questions to ask before buying a used generator, beyond just hearing it start.
A generator that starts up in the seller's compound doesn't tell you much on its own — plenty of generators run fine for five minutes and then reveal their problems under a real load, over a longer stretch, or after being moved. Here's what's worth asking and checking.
Ask how many hours it's actually run
Most generators have an hour meter, similar to an odometer on a car. Ask to see it, and treat a generator with no hour meter or one that looks like it's been reset with real suspicion. Hours run tell you far more about real wear than age alone.
Ask why it's being sold
A straightforward answer — upgrading capacity, switching to a different fuel type, moving house — is a good sign. Vague or evasive answers are worth paying attention to.
Test it under an actual load, not just idling
Ask the seller to run it with something plugged in — a fan, a bulb, anything with a real draw — rather than just letting it idle. A generator that runs smoothly with nothing connected can still surge, stall, or struggle once it's actually working.
Check the fuel system and filters
Ask when the fuel filter and oil were last changed, and if possible, check the oil yourself — dark, gritty oil suggests it hasn't been serviced recently. For petrol generators, check the tank for rust or sediment; for diesel, ask about the injector's condition if the seller knows.
Listen for the sound it makes and check the exhaust
Excessive smoke — blue, white, or thick black — usually points to a real mechanical issue, not something a quick service will fix. Listen for knocking or uneven engine sound rather than a steady, even hum.
Confirm the capacity actually matches what you need
A generator rated for a certain wattage on paper and one that can actually sustain that output under real Nigerian voltage conditions aren't always the same thing — ask the seller what they were actually running on it day to day, which tells you more than the sticker rating.
Agree on a short trial where possible
If the seller is open to it, running the generator for fifteen to twenty minutes under load before you finalize the sale is a reasonable ask for anything above a basic small unit, and a seller confident in what they're selling usually won't mind.
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