Mountfield SP46 18″ Petrol Lawn Mower

Why buy the Mountfield SP46 18″ Petrol Lawn Mower? Powered by a reliable STIGA ST 140 OHV 139cc Autochoke engine. Self-propelled drive system for effortless mowing on slopes and uneven ground. Generous 46cm (approx. 18″) cutting width, ideal for medium-sized lawns up to 1200 m². Versatile 3-in-1 cutting system: collect, mulch, or rear discharge. Large 60-litre hybrid grass collector with a ‘bag full’ indicator. Single-lever, centralised cutting height adjustment with 6 positions (22-65mm). A Hardworking Mower for Medium-Sized Lawns The Mountfield SP46 is a hugely popular self-propelled petrol lawn mower, expertly designed for homeowners seeking a reliable and straightforward machine. It’s an ideal choice for maintaining medium-sized lawns up to 1200 m², offering a perfect balance of power, performance, and user-friendly features. Its robust build and dependable engine make it a standout walk-behind mower for the British garden. Powerful and Reliable STIGA Engine At the heart of the SP46 is the high-performance STIGA ST 140 OHV Autochoke engine. This 139cc petrol engine provides consistent and reliable power, making light work of thick grass and undulating terrain. The Autochoke system ensures easy starting from cold, so you can get to work without hassle. With a fixed RPM of 2900, the engine delivers optimal power for a clean and efficient cut every time. Efficient Cutting & Collection The SP46 boasts a robust 46cm steel cutting deck, ensuring durability and a precise cut. Adjusting the cutting height is simple, thanks to a centralised single lever offering six different positions, ranging from 22mm to 65mm. This versatility allows you to adapt to varying grass conditions throughout the season. Clippings are efficiently gathered in the spacious 60-litre hybrid grass collector, which features a handy ‘bag full’ indicator to prevent overfilling and blockages. Mulching for a Healthier Lawn For those who prefer to save time and naturally fertilise their lawn, the SP46 comes with a mulching plug as standard. By inserting the plug, the mower finely chops the grass clippings and redistributes them back onto the lawn surface. This process returns valuable nutrients to the soil, promoting healthier, greener growth and eliminating the need for trips to the compost heap. Designed for Durability and Comfort Built with a sturdy dark grey steel chassis, the Mountfield SP46 is made to last. The self-propelled rear-wheel drive, moving at a comfortable 3.7 Km/h, takes the strain out of mowing, especially on sloped gardens. User comfort is enhanced by the ergonomic, soft-grip handlebar, which is both adjustable and foldable for easy storage. Weighing just 26kg, it remains easy to manoeuvre around garden obstacles. As an authorised UK dealer for Mountfield, Sims Garden Machinery provides more than just a box. With a heritage spanning over 100 years, the business offers expert guidance and complete peace of mind. The team invites customers to visit the Stratford-upon-Avon showroom to see a wide range of walk-behind mowers. The trained sales staff can provide tailored advice, while the workshop’s trained mechanics ensure comprehensive aftersales support. For local customers, every Mountfield SP46 petrol lawn mower comes with a free Pre-Delivery Inspection (PDI), local delivery, and a full handover demonstration, ensuring the machine is ready to use and the operator is confident in its functions. This commitment to service sets Sims apart from online-only retailers. Not sure which machine or part is right for you? Our team is here to help. Contact us today for expert advice. Technical Specification Specification Value Power Source Petrol Power 2.2 kW Engine Brand STIGA Engine Model ST 140 OHV Autochoke Powered by STIGA Displacement 139 cm³ Engine Rotation Speed 2900 rpm Starter Recoil Fuel Tank Capacity 0.75 L Engine Oil Tank Capacity 0.5 L Maximum Mowing Area 1200 m² Driving Self-propelled Traction Rear-wheel drive Speed Forward 3.7 Km/h Cutting Method Collecting, Mulching, Rear discharge Cutting Width 46 cm Deck Material Steel Cutting Height Adjustment Centralized Cutting Height Positions 6 positions Cutting Height Range 22 – 65 mm Collector Capacity 60 L Collector Type Hybrid with warn indicator Handlebar Type Ergonomic soft grip (Adjustable & Foldable) Wheels 200 / 200 eco grooved wheels on bearings Guaranteed Sound Power Level (LwA) 96 dB(A) Weight 26 kg Product Dimensions (L x W x H) 1570 x 540 x 1100 mm SKU 2L0482048/M21 EAN/UPC 8008984839090 Why buy from Sims Garden Machinery? Authorised main dealer We are authorised dealers for leading brands, meaning genuine parts, manufacturer-approved training, and warranty support you can rely on. Real people, real support No call centres. No ticket systems. Just a knowledgeable local team you can speak to when you need help. Expert advice — not pushy sales Our team are trained mechanics and product specialists, so you get honest, practical advice based on how you’ll actually use the machine. Established, independent family business We’re a long-standing independent dealer with deep roots in the local area — built on reputation, repeat customers, and word of mouth. Frequently Asked Questions What size garden is the Mountfield SP46 suitable for? The Mountfield SP46 is ideally suited for medium-sized gardens, with a recommended maximum mowing area of up to 1200 square metres. Its 46cm (approx. 18″) cutting width and self-propelled drive make it efficient for lawns of this size. What are the cutting options for this lawn mower? This is a versatile 3-in-1 mower. You can choose to (1) collect the clippings in the large 60-litre grass bag, (2) use the included mulching plug to finely chop and return nutrients to the lawn, or (3) use the rear discharge option for when collection is not necessary. Does this mower come assembled? The mower arrives from the manufacturer mostly assembled in the box, requiring only simple steps like attaching the handlebar. However, when you purchase from an authorised dealer like Sims Garden Machinery, local customers benefit from a free Pre-Delivery Inspection (PDI), which means the machine is fully built, tested, and filled with oil and fuel by our trained mechanics before delivery. How do I adjust the cutting height on the SP46? The cutting height is very easy to adjust. The SP46 features a centralised height adjustment system, controlled by a single lever located next to one of the rear wheels. This lever allows you to select from 6 different cutting heights, ranging from 22mm to 65mm, to suit the condition of your lawn. User Manuals / Downloads View Mountfield Brochure