Everything you need to know about petrol lawn mowers

Powerful and robust, petrol-powered lawn mowers continue to be the most popular choice of lawn mower for UK homeowners. Perfect for larger lawns and less formal grassed areas such as orchards, petrol-powered mowers are known for their durability, reliability and flexibility.

If you’re considering buying a petrol lawn mower, it’s important to consider all your options. For example, petrol mowers are often heavier and louder than mains-powered or battery-powered counterparts, but with good reason. In this article, we’ll talk you through everything you need to know about this powerful gardening tool. Read on to discover the essential information you need to know to make an informed decision based on your requirements.

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What are petrol lawn mowers?

An essential tool for keeping your garden lawn neatly cut and cared for, petrol lawn mowers are powered by an engine, using four-stroke petrol as power instead of mains electricity or a battery.  Arguably one of the more powerful types of lawn mowers, petrol mowers don’t have the restriction of a power cable or mains electricity supply and delivering longer run times than battery-powered models making them ideally suited to large stretches of lawn. This means they lend themselves to professional use as well as larger gardens and overgrown grass, which they can cut with consistency, control and ease. 

Types of petrol lawn mowers

Rotary petrol lawn mowers

Rotary mowers are the most popular type of petrol lawn mower in the UK. They feature a horizontal blade that rotates at high speed beneath the mower deck, cutting the grass as the mower moves forward. Rotary mowers are known for their powerful performance, wide cutting widths (40-55cm), and versatility in handling different grass conditions. Many models also offer features like self-propulsion, mulching and grass collection.

Check out our petrol rear roller rotary mowers and petrol 4-wheeled rotary mowers for the perfect specification to suit your needs, budget and lawn type.  

The Green Reaper recommends:

Webb RR17SP Supreme 43cm (17") 3-in-1 Self-Propelled Rear Roller Petrol Lawn Mower	Cobra MX484SPCE 4-in-1 4-Speed Self-Propelled Petrol Lawn Mower (Electric Start)

Cylinder petrol lawn mowers

Cylinder mowers use a reel of blades that spin vertically to cut the grass in a scissor-like action. They are often preferred for their precise, close-cut finish, making them a good choice for well-manicured, formal lawns. Cylinder mowers range in cutting width between 35cm and 60cm. Compared to rotary models, they require more regular maintenance to keep the blades sharp. Cylinder petrol lawn mowers are generally more expensive than rotary mowers and all feature front and rear rollers to achieve a defined, striped lawn finish

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The Green Reaper recommends: Cobra Fortis 20B 51cm/20" Self-Propelled Petrol Cylinder Lawn Mower

Hover petrol lawn mowers

Hover mowers use a cushion of air so that the mower operates above the ground, or ‘floats’ rather than relying on the more traditional mower design that incorporates wheels. Hover mowers are generally considered more suitable for cutting around obstacles, edges and sloping terrain. Highly manoeuvrable, petrol-powered hover mowers typically have cutting widths of around 50cm and less power than rotary models, but less power enables a more lightweight design, making them a great choice for grass-covered banks and uneven lawns.

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The Green Reaper recommends: Cobra AirMow 51B Petrol Hover Mower

Petrol scythe lawn mowers

Ideal for both residential and semi-commercial use, a petrol scythe lawn mower features a scythe blade, taking inspiration from traditional agricultural tools. The dual reciprocating blades slice through longgrass to deliver uniform cuts, with a petrol-powered engine to ensure minimal strain on the mower itself. Petrol scythe mowers can be used in remote locations for long periods making them a perfect choice for overgrown or neglected paddocks, orchards and meadows. 

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The Green Reaper recommends: Lawnflite BM87-35 Scythe Mower 34" Bar

Petrol wheeled trimmer lawn mowers

Equipped with sturdy wheels, wheeled trimmer mowers provide stability and smooth operation across various surfaces, including uneven terrain. Commonly also known as a wheeled brush cutter, they feature a rotating cutting head fitted with durable nylon line for tackling overgrown grass and brush. The outfront cutter deck can be used along edges, fences and obstacles that are difficult to reach with traditional mowers, whilst the nylon cord can also safely trim around trees. Their design and impressive cutting power is a less strenuous alternative to a traditional hand-held brush cutter for cutting though rugged areas of vegetation.

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The Green Reaper recommends:  Cobra WT56B Wheeled Trimmer Mower

Petrol field and brush mowers

All-terrain petrol mowers such as field mowers and brush cutters are optimally designed to handle tough, unpredictable terrain such as wild brambles, weeds, thick grass and even saplings. Fitted with a powerful petrol engine, fabricated cutting decks and heavy-duty cutting blades, all-terrain field and brush mowers are suited to semi-commercial use to keep dense vegetation at bay without the need of larger, heavier machinery. 

Shop petrol all terrain lawn mowers

The Green Reaper recommends: Billy Goat BC2601HM Outback 10.2hp/26” All Terrain Field & Brush Mower  

Petrol flail mowers

Designed for heavy-duty professional and intensive work on the toughest terrain, petrol walk-behind and towed flail mowers will plough through rough grass and scrubland, even on slopes. They’re also ideal for use in places where flying debris could cause damage - flails generally glance over foreign objects rather than catching and throwing them.

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The Green Reaper recommends: Orec Bull HR662 65cm Petrol Flail Mower

How do petrol lawn mowers work? 

At the heart of a petrol lawn mower is a small internal combustion engine. The engine used for all petrol mowers is a 4-stroke engine which powers the cutting blade(s) of the lawn mower, predominantly direct from the engine’s driveshaft or through the use of a belt or gears. These are key features of a petrol-powered mower, allowing the blade to spin efficiently at approximately 3,000rpm (revolutions per minute) to cut the grass efficiently and to your standard. 

The operational mechanism of petrol lawn mowers, in a nutshell: 

1. Petrol is drawn from the fuel tank and mixed with air in the carburettor.
2. The fuel-air mixture is drawn into the engine cylinder and compressed by the piston.
3. The compressed mixture is ignited by a spark from the spark plug, causing the piston to be forced downwards.
4. This downward motion of the piston turns the crankshaft which rotates the lawn mower blade.
5. The exhaust gasses are expelled from the cylinder, and the cycle repeats.

The Green Reaper recommends:  Masport 150 ST SP L 3-in-1 Self-propelled Petrol Lawn Mower 

Engine capacity and power rating according to lawn size

Features of a petrol lawn mower

Many petrol lawn mowers also incorporate additional features such as: 

SELF-PROPULSION - This eliminates the need to push the mower forward, which is essential for larger lawns or lawns with inclines	GRASS COLLECTION - This keeps the lawn tidy by depositing the grass clippings into a grass collection box or bag for easy disposal.
MULCHING - This is a great way to utilise clippings as a natural fertiliser	SIDE DISCHARGE - Ideal for longer grass, the grass clippings are side discharged to the right of the lawn mower as you walk behind it
ADJUSTABLE CUTTING HEIGHT - This allows you to set your cutting blade at a height that suits your desired length, usually between 20-100mm	VARIABLE SPEED - The speed of the lawn mower can be set to match the pace of the user and grass conditions
ELECTRIC START - For convenience and effortless starting

Choosing the right petrol rotary lawn mower

If you’re considering investing in a petrol rotary lawn mower, it’s important to consider the following:

Lawn size and lawn terrain

As a general rule, push walk-behind rotary lawn mowers are ideally suited to flat lawns less than 700 square metres in size containing obstacles such as island flowerbeds as they are easy to handle, whereas larger, perhaps sloping, lawns over 700 square metres, would benefit from a self-propelled model.

Engine power

Lawn mower manufacturer’s tailor their selection of engine power measured in horsepower in relation to the size of the cutter deck. The wider the deck, the more power is needed.

Start method

The most common method of ignition is recoil start whereby a nylon cord is pulled to turn over the engine, but this requires some effort on the part of the operator. Electric start lawn mowers are equipped with a battery and easily start up with the turn of a key or push button.

Cutting width 

Ranging from 40cm to 55cm in width, basically the wider the mower’s cutting width the fewer passes you will need to make resulting in finishing the job done quicker.

Grass cutting options 

The majority of small decked lawn mowers simply offer cut and collection. Lawn mowers with a medium to large deck size additionally provide mulching and side discharge options referred to as 3- or 4-in-1.

Deck quality 

The material used to construct the deck determines its strength and durability. Polypropylene or aluminium decks tend to be lightweight and do not rust. Decks made of steel are stronger, less expensive, but have the tendency to weigh heavier.

Speed

Push petrol rotary lawn mowers require effort to propel them forward. Self-propelled models feature a speed control lever which, when engaged, causes the mower to move forward at a single speed by itself so the user only has to guide it. An added feature on self-propelled lawn mowers is variable speed which enables the speed to be adjusted via a lever to match the walking speed of the operator and the mowing conditions. Variants include 2-speed, 3-speed, 4-speed and infinitely variable.

Machine weight

Considering the weight of a lawn mower is vital to ensure you are not lumbered with a machine that’s too heavy to handle, particularly if transporting the machine between mowing areas.

Handle design 

Folding handlebars are ideal for transportation and storage as the lawn mower takes up less room. Models with quick release cam locks make height adjustment simple and tool-free to suit the individual operator.

Lawn mower cost 

The cost of an entry-level, domestic lawn mower starts at around £170.00, whereas a top-of-the-range, professional mower can set you back £2,000 upwards, but luckily there are plenty of models to choose from in between. Affordability is another key factor to consider when choosing a petrol lawn mower. Finance options are available to allow you to spread the cost to suit your budget. 

Brand reputation

Every product on offer on The Green Reaper’s website features a brand tab containing important information about the brand to help make an informed decision before purchasing. Our brand page shows all the reputable brands on offer. 

Warranty 

All petrol lawn mowers are backed by a manufacturer’s warranty to cover any genuine faults which may develop. The length of the warranty, ranging from one to five years, is dependent on the brand and is often subject to registration of the machine on the manufacturer’s website.

Pros of a petrol-powered mower

Powerful performance: Petrol engines provide significantly more power than electric motors, allowing petrol mowers to handle thicker, taller and more overgrown grass with ease. This makes them ideal for larger gardens.

Extended runtime: Petrol mowers can typically run for 30-60 minutes on a single tank of fuel, compared to 20-30 minutes for cordless electric models. This extended runtime is useful for covering bigger areas without needing to recharge or refuel.

Wider cutting width: Petrol lawn mowers often have a cutting width of 40-55cm, compared to 30-40cm for typical electric and manual mowers. The wider deck allows you to cover more ground in fewer passes.

Versatility: Many petrol mowers offer adjustable cutting heights, mulching capabilities, and the ability to collect grass clippings in a rear-mounted bag. This versatility makes them suitable for a wide range of lawn care needs.

Cons of a petrol-powered mower

Heavier and less manoeuvrable: Due to their larger engines and fuel tanks, petrol mowers tend to be heavier and bulkier than electric, battery or manual models. This can make them more difficult to push and turn, especially in tight spaces.

Louder operation: The internal combustion engine in a petrol mower is noisier than the electric motors used in mains electric and cordless models. This can be a consideration if noise levels are a concern, especially in densely populated areas

Fuel and maintenance requirements: Petrol mowers need to be refuelled regularly and require more ongoing maintenance, such as oil changes and air filter replacements, compared to electric and cordless mowers.

For all your petrol lawn mower needs, look no further than The Green Reaper!