A good used mower is one of the best value buys in the whole garden. A quality machine that cost several hundred when new can change hands for less than a third of that a few years later, and with a sharpened blade and an afternoon of basic servicing it will cut as well as the day it left the shop. A bad used mower, on the other hand, is a skip on wheels that will swallow your money in repairs. The difference between the two is about fifteen minutes of checks before any cash changes hands, and almost all of those checks you can do yourself in the seller’s garden without tools.
Insist on a Cold Start
This is the single most revealing test on a petrol mower, so set it up before you arrive. Ask the seller not to run or warm the machine up for you, because a cold engine tells the truth and a warmed one hides a lot. A healthy mower should fire within a few pulls of the cord, or a couple of seconds on an electric start, and settle straight into a steady idle. What you are listening and looking for is what happens next. Smoke is the language the engine speaks. A single puff on start-up that clears within seconds is nothing to worry about, just oil residue burning off.
Smoke that keeps coming is a warning, and the colour points to the fault. Blue smoke means the engine is burning oil, which usually traces back to worn piston rings or tired valve seals, and that is the most expensive problem on this list. White smoke that persists suggests moisture or a head gasket weeping. Black smoke is a richer fuel mixture, often nothing worse than a carburettor that needs cleaning or adjusting after a winter on stale petrol. An engine that starts but then hunts up and down, surges, or stalls when you let go of the choke is almost always suffering from a gummed-up carburettor, which is common, cheap to put right, and a perfectly fair reason to knock money off the asking price.
The Compression and Oil Checks
With the engine off and the spark plug lead pulled for safety, pull the starter cord slowly through one full stroke. You should feel a firm resistance build at the top of the stroke as the piston compresses, followed by a slight rebound. That resistance is the compression that makes the engine run. If the cord pulls through easily with almost no resistance, the compression is low, which points to worn rings or burnt valves, and on an inexpensive mower that is the moment to walk away. Then pull the dipstick. Clean amber oil filled to the mark says the machine has been looked after. Oil that is milky or cream-coloured means water has got into it, often from a head gasket. Black sludge means servicing has been skipped for years, and an over-full level that smells strongly of petrol means fuel is leaking past the carburettor into the sump.
One check catches the fault that no service can fix. Tip the mower up to look underneath, always with the carburettor and air filter side facing upwards so oil cannot flood into them, and spin the blade slowly by hand while watching the central bolt. If the bolt and blade rotate in a clean flat circle, the crankshaft is straight. If the blade wobbles or the bolt traces a cone as it turns, the crankshaft is bent, almost certainly from the blade striking a buried root or stone at speed. A bent crank is terminal on a domestic mower and no amount of haggling makes it worth buying. While you are under there, look at the blade itself for cracks, deep gouges, or so much metal ground away by repeated sharpening that little remains.
Decks, Drives and the Rust That Matters
A film of surface rust on a steel deck is normal and harmless. What you are hunting for is rust that has eaten through. Press and poke the thinnest, flakiest areas, especially around the edges and the discharge chute, because a deck that has perforated or crumbles under a thumb has lost its structure and will only get worse. On plastic-decked models the equivalent failure is cracking, so flex the deck gently and look for splits radiating from the mounting points. If the machine is self-propelled, do a lap of the lawn or the drive and feel how the drive engages. It should pull away smoothly and hold a steady speed, not slip, judder or lurch, since a worn drive belt or a tired gearbox is one of the dearer repairs. Try every wheel-height adjuster too, because seized adjusters are extremely common and a real nuisance to free.
Battery and corded mowers shift the checklist. On a cordless machine the battery is the expensive consumable, and a replacement pack can easily cost a third of what the whole mower is worth, so ask how old the battery is and roughly how many seasons it has done, then run the mower and watch how quickly the charge falls. Make sure the correct charger is included and look for corrosion on the battery terminals and contacts. On a corded electric mower, run the full length of the cable through your hands feeling for tape, joins or nicks in the insulation, walk away from any that have been repaired, and never use one without a residual current device in the socket. The same care that makes a battery mower a good buy new applies double second-hand.
It pays to think about where you buy as much as what you check. A machine sold by someone moving house or downsizing their garden is often a genuine one-owner bargain, while a yard full of mowers usually means a trader flipping unknown stock with no service history behind any of it. Ask why they are selling, when it was last serviced, and whether the handbook is included, because a straight and detailed answer is itself a good sign about how the machine has been treated. Timing matters to your wallet as well. Prices for petrol mowers soften through autumn and winter when nobody is thinking about grass, so a patient buyer who shops in the off-season, turns up ready to collect, and pays cash will almost always do better than someone scrambling for a machine on the first warm weekend of the year.
What to Pay and When to Walk Away
The best value sits with the brands that were built to last in the first place. Names such as Honda, Hayter, Mountfield, Stihl, Cobra and Webb hold together for many years and keep their spare parts available, so a well-serviced example from one of those at perhaps a third to a half of its new price is money well spent. The cheapest supermarket and own-brand mowers are rarely worth buying used, because parts dry up quickly and a fault that costs more than the machine ends its life. Walk away the moment you count two or more serious red flags together: persistent smoke, low compression, a wobbling blade, a deck that has rusted through, or a seller who will not let the machine start from cold and grows cagey when you ask why.
Whatever you buy, budget for a service straight away, because it is what turns a tired mower into a dependable one and it is cheap. A new blade costs around £12 to £20 (roughly $15 to $25), and a spark plug, air filter, fresh oil and a carburettor clean add perhaps another £20 to £30 (about $25 to $40) in parts. For well under £50 (around $65) all in, a machine that ran roughly when you tried it can be made to start first pull and cut cleanly, which is exactly the work covered in a pre-season mower service. Read the spending the same way you would when deciding what you pay more for on a mower: a scored cylinder bore or a bent crankshaft is the end of the road, but almost everything else on a quality machine is a fixable, and negotiable, fault rather than a reason to give up on an otherwise sound bargain.
