Choosing and Buying a Lawn Mower - Electric, Gas, Battery
I Need a New Mower - Which Lawn Mower Should I buy?
This guide provides some tips on buying push or walk behind rotary gasoline (petrol) lawn mowers. It is by no means a comprehensive guide, but gives you some ideas about what to look out for when you go to a dealer or homestore and are confronted by the various models on display.
Topics covered include lawnmower type, horsepower, width of cut and deck type
What about Reel (Cylinder) Mowers - Could I Use One of Them?
A reel (also known as cylinder) mower without an engine is fine for a small area. You can use it to cut a larger area also and it provides great exercise and is likely in addition to strengthen your arms and back muscles. However it is by no means easy! Well at least I don't think so. I haven't used one of these for thirty years and can't recall seeing anyone using one in the recent past. I have one buried in the shed somewhere and I must resurrect it and see how difficult it would be to cut the lawn after all these years!
Reel mowers must be used on relatively short grass. Long and/or wet grass tends to clog them. They cut the grass by shearing it, just like a pair of scissors. The blades rotate and make contact with a bottom blade called the sole plate and these blades must be kept sharp and not rub tightly against this plate, otherwise pushing the machine becomes a chore. Regular lubrication is necessary also.
You can of course buy a reel mower powered by an engine. This type of mower is what is used to give the fine finish on golf courses and sports playing fields. They are considerably more expensive than a rotary mower and just like their unpowered counterparts, don't take kindly to very long grass.
Rotary Lawn Mowers
The most common type of small engine lawnmower uses a rotary action for cutting grass. This type of mower consists simply of a metal or plastic deck on which is mounted a vertical crankshaft engine. A metal cutting blade is attached to the end of the shaft. As the blade spins, it cuts the grass which is then thrown into a bag. Some mowers need to be pushed, others have self-drive and you just need to walk behind.
How Much Horse Power Do I Need?
The power of an engine is specified in horse power, abbreviated to hp. Alternatively the cc (cubic centimeter) capacity of the engine may be specified (i.e. the volume of the cylinder). There isn't a direct relationship between cc and horse power as the conversion factor varies from model to model and brand to brand and the efficiency of the engine. However the greater the cc, the greater the horse power. Power ranges are usually between 2 and 7 hp. 6 horsepower is roughly equivalent to 190 cc.
For a very small lawn of say 1000 square feet or less, a 3.5 horse power mower should suffice. Power becomes an issue when you tend to let the grass get long, and a mower with 5 or 5.5 hp has the advantage of being able to deal with long patches without slowing down or stalling. A more powerful engine will also be more capable of driving the mower forwards when the bag is fully laden and the wheels sink down into the soft surface of a lawn with lots of moss.
What Sized Cut?
The width of the cut produced by a rotary lawn mower is determined by the length of the spinning blade. This ranges from 15 to 25 inch but mowers with 18, 20 or 21 inch blades are probably the commonest. An 18 inch mower is usually a relatively neat machine and this makes it easier when you have to maneuver around trees, flower beds and other obstacles in lawns, or have to cut into corners.
How Big Should the Bag Be?
As big as possible. If the grass gets long or you have a large area to cut, you don't want to be regularly stopping to empty it. A good sized bag is 13 gallons equivalent to 2 cubic feet or 60 liters.
Steel, Aluminum or Plastic Deck
The deck or body of the mower which the engine sits on can be made from several materials:
- Steel Deck - This is usually the cheapest and strongest material from which decks are made. The disadvantage is that it corrodes over time unless the underside of the deck is cleaned regularly and allowed to dry before the mower is put into storage.
- Aluminum Deck - Not as strong as steel but won't corrode from just getting wet unlike steel. Corrosion occurs when a mower is left over winter with a coating of grass on the underside of the deck. This ferments and becomes acidic and this is what corrodes the aluminum. Sometimes near the end of the season, you keep thinking there will be one more cut and the mower then gets left in the garage until the grass gets long enough for this "last cut" to happen, which it never does. The mower then gets forgotten about and this is when corrosion occurs. So it is important to wash away any grass from the underside of the deck and store it in a dry garage or shed over winter.
- Synthetic Deck - Made from polymers under the brand names Xenoy and Nexite. These are more expensive than aluminum or steel. The advantage is that grass is less likely to stick to the underside and these materials don't corrode. The jury is out though on whether they last. Some people think they are great. Others reckon they aren't durable, crack from impact of stones and twigs and can become brittle due to exposure to the Sun.
Try to get a mower with a well known engine model. This is important if the engine needs to be repaired or serviced as regards getting spare parts. Briggs and Stratton, Honda and Tecumseh are well known engine manufacturers.
Adjusting Height of Cut
Some mowers have a single lever for adjusting the height of the deck and cut. This is very convenient. Others require you to adjust the wheels individually. The advantage of this is that one side of the mower can be raised. I think the single height adjuster is the best.
Weight of The Mower
If you have to move the mower around, weight needs to be taken into account. A smaller mower can be lifted into the trunk of a car with some effort, a larger mower may require two people to lift it.
Electric or Pull Start
Electric start mowers are an option if you don't have the ability to pull the starter cord on the mower. Obviously the extra parts add to the cost of the mower.
These mince up the grass and distribute it on the lawn so that you don't need to collect it in a bag.When the clippings decay, they return nutrients to the ground.
Mulching mowers are more expensive than non-mulching types and use more gas. Engines are usually higher powered and 5hp is at the bottom of the range.
Corded Electric and Cordless Rechargeable Battery Lawnmowers
So what are the alternatives to gasoline? Well you could go for an electric mower. These have several advantages:
- Lower noise
- Cost of electricity used is a fraction of that of gas
- No regular maintenance costs unlike a gas mower which requires replacement of oil, spark plug and air filter at regular intervals
- No exhaust fumes
- They always start first time and don't need to be pull started
- Mowers are much lighter so easier to manoeuver and lift into a car
- The power cord can be a nuisance and care needs to be taken to avoid running over it
- Potential danger of electric shock if used in wet conditions
- Power is generally limited to about 1500 watt or 2 horse power. Even a low powered gas mower would be rated at about 3.5HP. Because of this they are limited to regular cutting of grass (Cutting 6 inch long grass is not an option!)
Another option is a battery mower. These use a rechargeable 24 or 36 volt power pack. They offer all the advantages of an electric mower with the additional benefit of freedom from a power cord. However they can be quite heavy and are more suited to use on level ground without slopes because of the effort of trying to push the machine uphill. Generally these types of mowers are not self-propelled.