Mountfield S421HP Lawn Mower

Mountfield S421 HP Petrol Lawn Mower

Mountfield Garden Machinery

Mountfield S421 HP Petrol Lawn Mower

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Price Match Promise
Price Match Promise
We offer top prices, expert advice, and fast delivery. Found this machine cheaper? If it’s from an approved dealer with current prices, we’ll match it!* Call 0345 222 0231, use our live chat or our use our online form. *product must be in stock and ready for delivery, excludes bundle offers.
Included for FREE - 1 litre 4-stroke engine oil & fuel stabiliser
£239.00
RRP: £279.00 | SAVE £40
Discontinued
SKU
MOU-S421HP
Pay in 3 interest-free payments of £79.67.
Available on purchases of £30 to £2,000
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  • 4-in-1: Collect, Mulch, Rear & Side Discharge
  • 5 Year warranty* (Terms & conditions apply)
  • 41cm/16" cutting width
  • 60 litre grass bag
  • Mountfield 139cc OHV engine
  • Mulch plug included
  • Ideal for small/medium sized gardens
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Extremely popular & designed for general purpose. The S421 HP is a hand propelled machine with a 41cm (16in) cutting width and easy start Mountfield engine. 

This fantastic Mountfield S421 HP is a very versatile and easy to use hand propelled lawn mower. Ideal for small to medium sized lawns up to 20 x 20 m. This S421 HP 41cm lawn mower from Mountfield offers you a hard working machine and is great value for money. Thanks to the robust chassis powder coated in the classic “Mountfield red” together with quality components, you can expect this striking Mountfield hand propelled lawn mower to last you for years to come. Simple to maintain and very easy to keep clean thanks to the washing link that allows you to attach a hose to keep it free of loose grass clippings and muck.

A stand out feature of this S421 HP lawn mower from Mountfield is the superb 4-in-1 system that allows you to choose from mulching, discharging or collecting the grass. Which one you choose will of course depend on the length and condition of your grass. If your grass is longer you may wish to choose to either collect it or discharge it.

Discharging obviously saves you plenty of time and effort as you won’t need to empty the collection bag and the grass will be left to wilt naturally. The S421 will leave the grass cuttings spread about on your lawn rather than being left to rot on your compost heap. However, if you don’t like the idea of the grass being left on your lawn -You may have pets or children that might walk the loose grass into your house, for example - you can collect it in the generously sized 60 litre canvas grass collector.

The hard top of the collector minimises the amount of dust from flying up into your face as you work. The Mountfield S421 HP features a handy bag full indicator. Traditionally, some grass collectors don’t have this feature and therefore you do run the risk of allowing the collector to be overfilled resulting in the annoying job of having to clear out a blocked chute by hand.

The mulching feature is fantastic if your lawn is not too long, the clever system finely cuts the grass clippings and neatly returns them to the lawn where they will act as nitrogen-rich fertilizer saving you time and money. You won’t need to buy and sow additional grass fertilizer products. Your lawn will always looks its best with this handy feature, at no extra cost or effort from you. Also, you won’t need to empty the grass collector and Mountfield suggest you will save around 30% of the usual time it takes you to cut your grass.

The Mountfield 139cc 4 stroke engine is built to be economical on fuel and low on maintenance. It gives you plenty of power and is easy to start. The standard recoil rope system offers you reliability and ensures you of trouble free mowing for years to come.

A top safety feature of this Mountfield S421 is the operator presence control which means the engine only runs when you are holding onto the handles. Let go and the engine cuts out and the blades stop. This means the machine cannot be left to idle - this saves on petrol and also cuts the risk of accidents.

A great finish is guaranteed whatever the length of your grass thanks to the 6 pre-set cutting settings that range from 22mm - 65mm - ensuring you can tackle any length of growth with the greatest of ease and expertise. The 41cm cutting width is generous enough for small to medium sized gardens and allows you improved maneuverability when you need to mow up to edges and borders or around garden furniture and shrubs.

Mountfield’s commitment to customer satisfaction is second to none, therefore they offer you a generous 5 Year warranty* (Terms & conditions apply) on this product.

Please note: If you have a sloping garden you might like to consider the S421 PD self propelled model, also available from us here at Just Lawnmowers.

Included Accessories: Mulching Plug & Side Discharge Chute

Specifications
Art No 2L0431843/M19
Brand Mountfield
Power Source Petrol
Power Details Mountfield ST140 OHV 4 stroke engine / 139cc / 2.2kW @ 2900rpm
Engine make Mountfield
Starting Method Recoil Start
Design 4-Wheels
Cutter Deck Steel
Cutting Width 41 cm
Cutting Heights 22-65mm
Number Cutting Heights 6
Propulsion Manual
Collector Canvas with hard top 60 litres
Noise Value - Sound Power Level dB(A) 96
Weight 24kg
Warranty 5 Years (Terms & Conditions Apply)
Other Features Included Accessories: Mulching Plug & Side Discharge Chute

Mountfield

Mountfield have been one of the UK's best selling lawn mower brands since the 1960s. They’ve built a reputation for quality and reliability through their wide range of products. Mountfield first began manufacturing rotary lawn mowers in 1962 at their premises in Maidenhead, Berkshire. Despite the fact that today’s machines have very little resemblance to their ancestors, Mountfield garden machinery has always been made with high quality and good value for money in mind.

Mountfield aim to make gardening as pleasurable an experience as possible, and manufacture their products accordingly. Over the years they have continually developed their products to ensure they are both meeting and out-performing consumer expectations. Today they don’t just specialise in manufacturing of lawn mowers. They have a whole range of products to ensure that many gardening needs are met efficiently, from ride on mowers, to multi-tools and garden shredders.

Mountfield's lawn mower range is extensive. With hand pushed models, self propelled models, petrol, electric and cordless, there is something for just about everyone.

They produce 2 types of ride on mower; Lawn riders which are small enough to fit through a garden gate and a perfect choice for small to medium sized lawns and garden tractors for larger lawns. Mountfield’s hand-held range of garden machinery includes grass trimmers and brush cutters, hedge trimmers, leaf blowers, and chainsaws. They are all designed to be lightweight and easy to use. They are suitable for both domestic and professional users.

Mountfield have recently released their Freedom 48 range of cordless garden machinery. Once you have purchased a battery and a charger, you can use them for any of the product in the range as they all use the same battery.

Expertly Handled Delivery

From fast express parcels to our signature White Glove personal handover, we ensure your machinery arrives safely, quickly, and ready for work.

Standard Delivery

£9.99 (Eng/Wales) 1 - 3 Working Days
  • Reliable courier service for most items.
  • Items dispatched Mon-Fri.
  • Available to most UK Mainland addresses.
  • Next-day arrival possible in many cases.

Express Delivery

£9.99 (Eng/Wales) 1 - 2 Working Days
  • Priority dispatch for urgent orders.
  • Order before 2pm (Mon-Fri) for fastest service.
  • Available on many popular items.
  • Full email notifications for any delays.

Start 'N' Go

From £29.00 3 - 5 Working Days
  • Fully Assembled & Tested by our technicians.
  • Arrives on a secure pallet via 'Palletline'.
  • The courier will contact you to book a slot.
  • Ready to mow immediately on offloading.

Start 'N' Go +

White Glove Service 3 - 5 Working Days
  • Personal Delivery on our own transport.
  • Full Demonstration: We show you how to use it.
  • Zero Waste: We take pallets and crates back.
  • Available on select products in England & Wales.

Important Delivery Information

Working Days:
Please note that Saturday & Sunday do not count as working days. Orders placed over the weekend are processed on the following Monday (or Tuesday during Bank Holidays).
Booking Your Slot:
For Start 'N' Go orders, Palletline will contact you directly. For Start 'N' Go+, our own team will call you. Please ensure a daytime contact number is provided.
Ride-On Mowers:
Start 'N' Go rates for Ride-Ons start at £69 (Garden Riders) and £79 (Tractors). Start 'N' Go+ rates for Ride-Ons start at £99.00 (for both riders and tractors). This specialist service is currently available for Mainland England and Wales postcodes.

*Flat rates apply to Mainland England and Wales. Additional charges apply to Scottish Mainland and offshore addresses. Refer to specific models for accurate delivery guides.

Delivery Frequently Asked Questions

How much is delivery?

We charge a flat rate of £9.99 for all orders (Standard or Express) being sent to mainland England and Wales addresses. Additional charges apply to Scottish mainland addresses and offshore locations.

How long does delivery take?

Standard Delivery: Usually 1-3 working days.
Express Delivery: Usually 1-2 working days (often Next Day).
Start 'N' Go / Premium+: Usually 3-5 working days due to expert assembly.

Do you deliver on Saturdays?

Our standard delivery service operates from Monday to Friday. Saturday and Sunday do not count as working days.

What is Start 'N' Go/Premium+ and how does it affect delivery?

These services mean your machine is fully assembled, fuelled, and tested. Delivery typically takes 3-5 working days due to the assembly and specialist transport.

Will the courier call me before delivery?

For Start 'N' Go, Palletline will contact you. For Start 'N' Go+, our team will call to arrange a timed slot.

Can I track my order?

Yes. You will receive an email containing your tracking information once dispatched.

What happens if my item arrives damaged?

Please notify us immediately. If noticed upon delivery, please sign as "damaged" or refuse the delivery.

Full Delivery Details and Information

We are very sorry but please be advised that for the foreseeable future we cannot despatch orders to Northern Ireland, Republic of Ireland, the Channel Islands or any UK offshore postcodes.

Please see below for a breakdown of our various delivery services, including rates. In all instances, you will receive notification of when your order has been dispatched, and where possible tracking information will also be provided. Please regularly check your email account for any updates.

STANDARD DELIVERY

Most items will be sent out on our Standard delivery service. This service is available to most of the UK mainland*. This service is 1-3 working days (if ordered Mon-Fri, stock permitting), but is usually sooner than this. In many cases, your item could arrive next working day. Please note: Saturday & Sunday do not count as working days. Orders placed over the weekend will be processed on the following Monday (or Tuesday if a bank holiday). Some products are 3-5 working days, please refer to the specific model for a more accurate delivery guide. In some rare cases, your item might take longer than expected to arrive. If there is a delay in delivery, we will let you know via email.

We charge a flat rate of £9.99 for all orders which are being sent to mainland England and Welsh addresses, no matter the cost, weight or size. Please see below for additional charges to Scottish mainland addresses*.

EXPRESS DELIVERY

We offer an Express delivery service on many items to most of the UK mainland*. These items will be dispatched as soon as we possibly can and will usually arrive within 1-2 working days and in many cases on the next working day (stock permitting if ordered before 2 pm, Mon-Fri). Please note: Saturday & Sunday do not count as working days. Orders placed over the weekend will be processed on the following Monday (or Tuesday if a bank holiday). In some rare cases, your item might take longer than expected to arrive. If there is a delay in delivery, we will let you know via email.

We charge a flat rate of £9.99 for all orders which are being sent to mainland England and Welsh addresses, no matter the cost, weight or size. Please see below for charges to Scottish mainland addresses*.

START 'N' GO

Our Start 'N' Go service is available to most of the UK mainland*. Products that receive our Start 'N' Go service will need to be assembled and tested before being wrapped and dispatched on a pallet. Because of this, delivery is 3-5 working days (if ordered Mon-Fri, stock permitting) but during quieter times this can be much sooner. Orders placed over the weekend will be processed on the following Monday (or Tuesday if a bank holiday). You will be contacted by the Transport Company 'Palletline' to book your delivery in. Please ensure you provide a daytime contact number on your order.

Ride-On Mowers - We charge a minimum rate of £69.00 (for smaller garden riders) and £79.00 (for garden tractors) for all Start 'N' Go orders. This service is available to most mainland England and Wales postcodes. We cannot currently offer this service to any Scottish postcodes.

Everything else - We charge a minimum rate of £29.00 for all Start 'N' Go orders which are being sent to UK mainland addresses (England, Wales and some Scottish addresses*).

START 'N' GO +

Our premium Start 'N' Go+ service is available on certain products to most of England and Wales. Products that receive this service will be assembled, tested and personally delivered by one of our team on our own transport. We will also fully demonstrate the product for you. Delivery is usually 3-5 working days (if ordered Mon-Fri, stock permitting) but during quieter times this can be much sooner. Orders placed over the weekend will be processed on the following Monday (or Tuesday if a bank holiday). We will contact you to book your delivery in. Please ensure you provide a daytime contact number on your order.

Ride-On Mowers - We charge a minimum rate of £99.00 for all Start 'N' Go+ (plus) orders. This service is available to most mainland England and Wales postcodes. We cannot currently offer this service to any Scottish postcodes.

Everything else - We charge a minimum rate of £29.00 for all Start 'N' Go+ (plus) orders. This service is available to most mainland England and Wales postcodes. We cannot currently offer this service to any Scottish postcodes.

*Scottish Addresses

As of May 2024, we can no longer deliver ride-on mowers (lawn tractors, garden riders, front deck & zero-turns) to any Scottish Postcodes. Unfortunately we have been unable to source a reliable and cost efficient transport service north of the border.

If you are ordering any other product on our 'Start N Go' service additional charges will apply (in addition to our advertised standard charges).  If you wish to check if additional charges will apply to your postcode you can call us or use our Online Chat during office hours, or use the contact us page, please quote your full postcode and the make & model of the item(s) you wish to order.  You can still place your order through the website without receiving a quote and we will be in touch via email after the order has been placed to advise if there are any additional delivery costs.

For all other products, depending on the postcode and size of the item(s) you are ordering, additional charges will apply.  If you wish to check if additional charges will apply to your postcode you can call us or use our Online Chat during office hours, or use the contact us page, please quote your full postcode and the make & model of the item(s) you wish to order. You can still place your order through the website without receiving a quote and we will be in touch via email after the order has been placed to advise if there are any additional delivery costs.

For more information call our sales team on 0345 222 0231

At justlawnmowers.co.uk, we are passionate about garden machinery and helping you achieve a beautiful, well-maintained garden. As a trusted online retailer specializing in lawn mowers and garden equipment, we are dedicated to providing you with the highest quality products, expert advice, and exceptional customer service.

Our Commitment to Excellence

Professionalism:

We take pride in our professionalism and deep understanding of lawnmowers and garden equipment. Our team consists of knowledgeable experts who stay up-to-date with the latest industry trends and advancements. We are committed to sharing our expertise with you, ensuring that you make informed decisions and find the perfect lawnmower for your specific needs.

Reliability:

When it comes to your gardening equipment, reliability is crucial. That's why we carefully curate our product selection, partnering with leading brands known for their quality and durability. We want you to have peace of mind knowing that the lawnmower you purchase from us will deliver outstanding performance and stand the test of time.

Exceptional Customer Service:

At justlawnmowers.co.uk, we prioritize your satisfaction above all else. Our friendly and dedicated customer service team is here to assist you every step of the way. Whether you have questions about our products, need advice on maintenance and care, or require support after your purchase, we are always ready to provide prompt and helpful assistance. Your gardening success is our ultimate goal.

Our Approach

Informative and Friendly:

We believe in providing information in a way that is both informative and friendly. Our content is designed to be easily understood, jargon-free, and engaging. We want to empower you with the knowledge you need to make confident decisions about your lawnmower and garden equipment.

Join Our Growing Community:

We invite you to join our growing community of homeowners, gardening enthusiasts, and professionals who trust justlawnmowers.co.uk for their lawnmower and garden equipment needs. Explore our wide range of products, read our informative blog articles, and engage with us on social media platforms. We are here to support you on your gardening journey, and we look forward to being a part of your success.

Thank you for choosing justlawnmowers.co.uk. Let's create a greener and more beautiful world together!

Our Pledge

We are a family business with 60 years experience in the horticultural and leisure business. We are very well qualified to offer you the consumer the best products that are available today. Our massive buying power and knowledge of these products allow us to offer you unbeatable deals. Our products are chosen for their quality, reliability and price. We are deeply committed to give you the best possible service at all times.

Why Buy From Us?

  • Fast, affordable delivery to your door (usually next working day, if ordered before 2pm - excludes some Scottish and offshore postcodes)
  • We are authorised agents/dealers for most leading garden machinery brands
  • Our friendly sales staff have extensive knowledge of all the products we sell
  • We dispatch many orders from our own extensive warehouse facility here in North Norfolk
  • Direct access to over £20 million of stock via our main dealer accounts with manufacturers
  • Having been around since 1965, we know a thing or two about garden machinery!

Help and Advice

If you need some advice about which product is best for your needs, just call our friendly and helpful sales team on 0345 222 0231 (Mon-Friday 8.30am - 5.00pm, excluding Christmas & bank holidays) or use our chat facility at bootom of your screen. You can also contact us using our online form.  With a wealth of experience and expert knowledge about all the products we sell, they can answer your questions quickly, accurately and reliably. You should then have a much clearer picture about which product is right for your specific needs.

No Hidden Costs

When you buy from us, there are no hidden costs; all our prices include VAT and even better, we offer fast delivery with a fixed delivery price, no matter the size or weight *. Plus, by selling online we keep our overheads low, so we always have discounted prices; 365 days a year.

Buy Online With Confidence

Perhaps you are still a little concerned about buying online? Don't be; we use Braintree 128 bit encryption technology and PayPal to ensure that buying from us is always safe, secure and reliable.

Support

Our online support can handle all your after sales needs including consumables, spare parts, servicing, and more. Visit Support.

*excluding Start 'N' Go products

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