Petrol Earth Augers: Engine Drills for Holes in the Ground

One-person augers suit holes up to about 200 mm in diameter, while two-person models handle up to 250–300 mm and heavy, stony soil. There are also trolley-mounted models and models with reverse, which make it easier to free a jammed auger. See how to choose a petrol breaker, drill and post driver.

Petrol earth augers usually have a 43–72 cm³ two-stroke engine rated at 1.4–3 kW (about 2–4 hp), and some models are four-stroke. A larger engine is needed for big diameters and hard soil but adds weight and reaction force. See differences between two-stroke, four-stroke and diesel engines and engine displacement, power, torque and RPM: how to compare engine-powered equipment.

Auger diameters are usually 60–300 mm: 100–200 mm is often enough for posts and 200–300 mm for tree planting. A standard auger reaches 0.8–1 m deep, and an extension lets you drill deeper. Check whether an auger is included and what shaft fitting diameter it uses.

The gearbox reduces speed and increases torque, while a centrifugal clutch protects the engine from overload. A metal-housed, two-stage gearbox is more durable in hard soil with roots. For drivetrain parts: how to choose drivetrain parts: gears, shafts, bearings, clutches and belts.

Most models have a manual recoil starter, primer bulb and choke, while an easy-start system reduces the pulling force. The throttle and stop switch should be reachable without letting go of the handles.

A two-stroke auger runs on a petrol and two-stroke oil mix, usually 1:25–1:50, and the gearbox needs its own grease. Always use fresh mix at the correct ratio. More details: fuel, engine oil and two-stroke mix: how to choose and use them correctly.

Petrol earth augers weigh 8–15 kg without the auger. Wide rubberised handles and an anti-vibration system help control the tool and reduce fatigue. See what is an anti-vibration system and what is vibration level.

When the auger hits a stone or root it can twist the handles sharply, so keep a stable stance, check for underground utilities and wear safety glasses and ear defenders. After work, clean the auger and check the gearbox grease, air filter and spark plug. Read how to safely use internal-combustion-engine tools and equipment, how to choose safety glasses, how to choose hearing protection, how to maintain and store motor tools and engine-powered equipment and how to choose spare parts for gasoline and diesel engines.