The most widely found home and light commercial sit on lawn mowers within the UK are the mid-mount and front-mount variants.

The Mid-mount Sit On Lawn Mower

The mid-mount sit on lawn mower, which is often referred to as the lawn or garden tractor, can be easily identified by its position of the cutting deck between the front and rear wheels of the machine.  Since the cutting deck is positioned below the operator, the field of view around the lawn mower is excellent. These particular machines also allow the operator to manoeuvre and cut grass within millimetres of the periphery of an obstruction such as a tree.  Mid-mount sit own lawn mowers are constructed with either 2 or 4 wheel drive and are powered by either air or water-cooled petrol or diesel engines.

The Front-mount or Out-front Sit On Lawn Mower

Front-mount or out-front sit on lawn mowers, as the names imply, are manufactured with the cutting deck at the front of the lawn mower.  These particular sit on lawn mowers offer exceptional manoeuvrability with a turning circle of nearly zero degrees.  An advantage of a front mounted cutting deck is that it provides an excellent view of the cutting area allowing the operator to cut immediately adjacent to trees, hedges and other obstacles.  These lawn mowers also offer firm and steady manoeuvring on inclines for added safety.  Front end sit own lawn mowers are also constructed with either 2 or 4 wheel drive and are powered by either air or water-cooled petrol or diesel engines.

Lawn Mower Size

Clearly, the area of a lawn or paddock will often dictate the required cutting width of a sit on lawn mower.  The size of a cutting deck will determine how many trips will be required to and from the edges of the cutting area to complete the job of cutting the grass.  Other considerations of trees, bushes and other obstacles, particularly the width between any obstacles on the lawn or paddock, will also determine the overall cutting deck size.  Therefore, it would not be a wise choice to purchase a sit on lawn mower that is unable to pass between two trees or be transported down any garden path.  The slope of the lawn or paddock is also another vital consideration.  It is imperative to operate a sit on lawn mower that will provide stability and safety and will not overturn during operation

Features of the Lawn Mower

Depending on what the desired finish is required, sit on lawn mowers come in different models, which can receive additional attachments.  If a manicured cut is required then a machine with a collection system and bag is required to gather the grass clippings for disposal.  However, if collection is not required then a sit on lawn mower with a simple side discharge system or a mulching cutting deck may suffice.

Lawn Mower Storage

The most common method of storing a sit on lawn mower at home is either in a garage or garden shed.  However, some owners prefer or have no other option but to store their lawn mowers outside under cover using a waterproof vinyl sheet or similar.  Unfortunately, this particular method of storage does not provide a great deal of protection from the elements or indeed from theft unless the machine is securely anchored to the ground.  Consequently, serious thought must be given to the storage of a sit on lawn mower when it is not in use.

Therefore, it would make sense to observe the following important safety rules when using a sit on lawn mower.

• Always read and understand the manufacturer’s instruction book.
• Adults who are familiar with the sit on lawn mowers instructions should only be allowed to operate it.
• Ensure that any object that can be thrown by the sit on lawn mower cutting deck, such as stones, wood, metal and childrens toys etc., are safely cleared away from the mowing area.
• Always wear eye protection when operating, cleaning, affecting a repair or making adjustment to a sit on lawn mower.
• Operators must always wear suitable clothing including long trousers and footwear. Never operate a machine with exposed feet or toes.
• Be vigilant and make sure there are no people or pets in the vicinity of the mowing area. If any person or animal enters the cutting area then stop the machine immediately.
• Passengers must never be carried on a sit on lawn mower.
• Always be aware of the mower’s discharge outlet to prevent damage to adjacent objects such as windows, trees and plants.
• Reduce the machine’s operating speed before turning.
• Never leave an engine running on an unattended sit on lawn mower. Apply the parking brake, disengage the cutting blades, switch off the engine and remove the ignition key when not in use.
• Operators must not use a sit on lawn mower when taking drugs or consuming alcohol.
• Do not smoke when operating, cleaning or servicing a sit on lawn mower.
• Always stop the machine’s engine before removing any attached collection bag or implement.
• When operating a sit on lawn mower near to roads or paths, ensure there are no vehicles or pedestrians present.
• Always mow up and down slopes and never across them.
• Select a lower speed for the sit on lawn mower before transgressing slopes to prevent gear shifts or stopping.
• Ensure that all movements across slopes are gradual and slow – try to prevent any sudden acceleration or quick changes in direction.
• Be vigilant for holes, bumps, ruts or objects in the mowing area – tall grass can easily hide them.
• Try to avoid stopping and starting on slopes. If the sit on lawn mower loses traction then disengage the cutting blades and proceed down the slope under braked control.
• Consult the manufacturer’s instruction book to see whether the machine requires improved stability through wheel height adjustment or counterweights when transgressing slopes.
• Always store fuel in a purpose designed containers and refuel the machine outdoors to prevent the capture and ignition of fuel vapours.
• Never add fuel to the fuel tank when the sit on lawn mower’s engine is running or is hot.
• Immediately replace any silencer on the machine that becomes defective.
• When examining the sit on lawn mower for damage or when cleaning, carefully remove the high-tension lead connector(s) from the spark plug(s) and replace them when finished.
• If the sit on law mower is equipped with more than one cutting blade, care must be taken when rotating one blade as the other blades may also turn.

• Ensure the fuel tank has enough fuel
• Inspect fuel tank and fuel delivery pipes for contamination or blockage, replace fuel filter if required
• If fitted, make sure any fuel cut off valve or switch is in the open position
• Check for loose electrical cable connectors on the battery and tighten if necessary
• Check for loose cable connectors on the machine’s safety switches
• Remove and inspect spark plug for wear or damage and replace if necessary

The engine on my sit on lawn mower refuses to turn over

• Battery is flat and will require recharging
• Main fuse has blown. Replace with new fuse of same amperage
• Inspect electrical wiring for any damage and repair any damaged wires
• Check for any loose electrical cable connectors on the sit on lawn mower

It is difficult to start the engine on my machine

• Ensure there is sufficient oil in the engine
• Inspect the air filter. Clean or replace the filter if necessary
• Remove and inspect spark plug for wear or damage and replace if necessary
• Check the fuel filter for blockage. Replace filter if required

My sit on lawn mower engine loses power or is not running easily

• Check engine oil level
• Examine air filter and housing for grass cuttings etc. Clean as necessary
• Check for dried matter, like leaves, around engine. Clean engine carefully with a brush
• Check spark plug for wear or damage. Replace if required
• Engine under strain. Select lower drive gear
• Grass too tall. Raise cutting deck
• Make adjustment to carburettor
• Inspect fuel filter for contamination. Replace filter if necessary

At fast speeds, my machine’s engine does not run smooth

• Check spark plug for damage and wear. Replace if necessary
• Inspect throttle mechanism and cable and make adjustments if required
• Check air filter and clean as necessary
• Inspect fuel filter for debris. Replace if required

My sit on lawn mower’s engine does not idle

• Inspect throttle control and cable and adjust if required
• Check spark plug for wear and damage. Replace if necessary
• Ensure air filter is clean
• Make adjustments to the carburettor

• Always wear clothing that can give you a degree of protection and in particular always wear trousers when operating a sit on lawn mower. This will help reduce accidental skin abrasions with objects such as plants and trees
• Eye protection is essential in dry cutting conditions. Wear safety glasses in these circumstances to help prevent dry grass cuttings and dust entering eyes, which could cause irritation, reduced vision or infections
• Whilst nearly all sit on lawn mowers have guards and housings to limit the amount of noise emitted by the machine’s engine and cutting deck when running, it would be advisable to wear ear protection to help further reduce these noise levels
• Driving gloves or similar will help your holding of the machine’s steering wheel and therefore have improved control of it, which will help reduce minor collisions and fatigue
• Ensure both hands are on but do not tightly grip the machine’s steering wheel as any sudden ‘kick’ from the steering wheel, which may be caused by the machine’s front wheels striking an unseen object or hole, could cause an injury or even broken thumbs
• Never operate a machine in bare feet. Wear correct footwear, for example, shoes and not sandals to help prevent accidental cuts to, crushing or loss of your toes and/or feet caused by the sit on lawn mower or collision with an object such as a plant or tree
• Tie any long hair back as this could be caught by throttle and cutting deck operation levers installed on the machine, which could cause personal injury, unnecessary distraction or may interfere with vision when operating the machine
• It would be advisable to wear a cap with a visor to help visibility in strong sunlight conditions when operating your sit on lawn mower to help reduce eyestrain and fatigue
• In strong sunlight conditions, apply an appropriate sun block to any exposed parts of your body, for example, your neck and arms, to help prevent sunburn and therefore reduce fatigue when operating your machine
• Adjust your machine’s seat to suit your requirements in order that you are sat comfortably and the operating controls, for example, throttle, cutting deck operation levers and brake pedal etc., are safely within your reach
• If your sit on lawn mower is equipped with a cup holder then take a drink with you in a sealed cup and consume it to help prevent dehydration and reduce fatigue whilst using the machine
• Ensure that any safety belt attached to the machine’s seat is correctly adjusted around your waist and secured to help prevent possible ejection from your sit on lawn mower and personal injury in the event of an accident or sudden stop

The starter motor on a sit on lawn mower starts the engine and will require a battery and alternator to operate it effectively. A properly maintained battery will provide between 3 to 5 years of service. Therefore, it would be advisable to understand the basic principles of battery maintenance. Here are a couple of tips for extending the life of a sit on lawn mower battery:

1. Always think of safety when working with batteries. Remove jewellery including watches to prevent short-circuiting between the metal parts of a sit on lawn mower and the positive terminal of the battery, which may cause serious skin burns. Charge a battery in a well-ventilated area, as hydrogen gas is emitted and is highly explosive. Wear safety glasses when handling or recharging batteries as sulphuric acid from a battery will damage eyes. Wear polyester overalls or clothing, as it is not affected by battery acid if accidentally splashed. Clean any spillages from batteries immediately.

2. When a machine is not in use, disconnect the battery to prevent ‘parasitic’ power draining of the battery through switches and any ancillary equipment connections. Make sure all electrical switches are in the off position. Always disconnect the negative cable first from the battery followed by the positive. When storing the machine over long periods, for example through the winter, disconnect and remove the battery and store in a dry and warm environment.

3. Periodically check the liquid electrolyte levels of lead acid (wet cell) batteries especially in warm weather conditions. Ensure the electrolyte level is approximately 8mm above the internal battery plates but below the neck of the fill tube to allow for expansion of the liquid. Top up levels using distilled water only. If overfilled, caution must be exercised, as the spillage will contain acid.

4. Soiled or corroded battery cable terminals may reduce battery power passing to the starter motor etc. Disconnect the battery from its cable connections and clean the terminals with a wire brush. Try to avoid liquid cleaners unless they are approved liquids for cleaning battery terminals. Ensure the terminals are dry before reconnecting them to the battery.

5. Check for bulges in the battery housing or liquid electrolyte leaks – use caution when inspecting the battery and wear gloves to protect hands from potential hazards. Damaged batteries should be removed and replaced immediately. Always dispose of sit on lawn mower batteries responsibly. If the battery will not retain its charge after several hours then serious consideration must be given to replacing it. Weak starting or uneven engine running might be a further cause of poor battery performance. Consult the sit on lawn mower’s manufacturers instructions for details of the correct battery type etc., before purchasing a new one.

It is paramount to maintain all aspects of a sit on lawn mower including the battery. Careful and proper maintenance will provide a more efficient machine that will help minimize potential problems in the future.