2_15.jpg Despite the variety of landscape contracting companies that exist, the mower is a universal element for almost all of them. Even many companies that now focus exclusively on design/build projects were probably originally founded by a guy with nothing but a pickup truck and a lawnmower.

However, as integral as the mower is for many green industry businesses, it's easy to underestimate the importance of one of the mower's most critical components: the engine. When it comes down to purchasing a mower, many contractors get caught up with elements like deck width and forward speed, and neglect to carefully evaluate the pros and cons of each model?s engine.

Of course, forward speed and width of deck are important, but what's powering that forward speed? What's spinning those cutting blades? The engine! Having the right one increases your productivity and decreases your downtime.

"Choosing an engine is a question of productivity," says Toro's Edric Funk, product manager for landscape contractor equipment. "The correct engine, with the correct amount of torque for any given application, directly translates into more production."

Choice of engine should be given as much weight as many of the other options you look for when buying a mower. "While the engine can't make up for a poorly-designed piece of equipment, a good engine is essential to reliable operation," says Pat Penner, marketing coordinator for The Grasshopper Company, Moundridge, Kansas.

If you're constantly pushing your mower's engine to its limit and beyond, it's going to guzzle more fuel, and break down sooner and more often. The more it's in the shop, the less time it's spending helping you make money.

Howard Mees is vice president of operations and equipment for ValleyCrest Companies -- landscape maintenance division -- Calabasas, California. He can talk for hours about mowers. But when asked what his company looks for in a mower engine, the first thing he says is simply, "Something that starts." It's the ultimate bottom line: who does your mower spend more time with, you or your mechanic?


When you think of your mower's engine, horsepower is probably the first thing that jumps into your mind -- how much you have, and how much you'd like to have. "Contractors never feel like they have too much power," says Funk. Mees laughs and agrees, saying, "Boys like their toys. Bigger is usually better."

Of course, a bigger, more powerful engine is usually accompanied by a bigger, more intimidating price tag. How can you tell how much is enough and how much is too much?

The simple answer is to decide on the width of the deck you want to operate. Typically, a wider deck will require more horsepower. However, this isn't the only factor to consider.

You should also examine what conditions your mower will be working in. Are your mowing conditions generally easy, or generally tough? Do you work on large, flat properties or landscapes with slopes and wet grass? If you're in tougher conditions, you might be glad you paid a few dollars extra for a higher horsepower machine that can cut through them more easily.

8_2.jpgWhatever conditions you face, buy an engine based on your most difficult sites. This means the engine will have plenty of power for your average jobs, and will burn less fuel and have a longer life because it won't always be running at maximum load.

How much time you spend mowing can also impact your horsepower decision. "In many cases, a smaller engine will turn the blades just fine," says Tim Kelley, Kelley's Landscaping, Alexandria, Louisiana. "But if you're doing maintenance all day long, you might need a bigger engine to hold up under constant use."

Generally, it's a good idea not to buy the lowest horsepower available, but don't always jump for the highest either. Instead, the middle-of- the-road power option can often be your best bet -- your investment will be affordable, but still give you enough power for tricky jobs.

The one exception is with walk-behinds. In this case, buying as much power as possible can be the winning decision. "Walk-behinds need some extra horsepower in case they're ever used with a sulky. They'll have to not only move the machine and spin the blades, but also transport the operator," says Mees.

Of course, the power of an engine doesn't depend on horsepower alone; torque matters as well. If you want an engine with a lot of torque, you have to go with a diesel. "Diesel engines can maintain a wide torque curve and are often favored for jobs where considerable power is required," says Penner.

A diesel engine can also allow you to use less fuel, because diesel fuel contains more energy per gallon than gas. You won't have to fill up as often. Diesel engines also typically have longer lives than gasoline engines, because they're made with more heavy-duty parts. This can be a blessing or a curse: the engine will last a long time, but might outlast the rest of the mower.

Some contractors find it beneficial to carry a lot of fuel with them, and save themselves frequent trips to the fueling station. These contractors often choose diesel engines. While there are a number of restrictions on how much gas you can transport, diesel has fewer limitations as far as transportation and storage. "I know many contractors who have switched to diesel for this reason," Funk says. "They find it more productive to be able to carry more fuel with them."

However, diesel engines can be difficult to start in cold temperatures, and require skilled mechanics for servicing. While some professionals might call diesel a 'better' engine with a longer life, they may still refuse to buy one, simply because any mechanic can work on a gas engine, but diesel requires an extra set of skills, which may complicate your maintenance procedures.

Finally, it can be important to consider any attachments and additional implements you plan on using with your mower. While the use of attachments such as vacuum collection systems, mulching systems, and snow removal implements might not be the cornerstone of your business, if you want to grow into any of those areas, your mower has to have the muscle to back you up. Most manufacturers make recommendations detailing the engine requirements for the implements they have available.

Reliability and maintenance

Of course, maintenance isn't an issue only when dealing with the matter of gas versus diesel. It should also be an important overall consideration in the purchase of an engine. Is your mechanic familiar with only one or two certain brands? If so, then perhaps you should stick to those. If you plan on using a dealer to service your mower, does he stock parts? Is he in a convenient location? If not, it might be a good idea to look for a different dealer. The bottom line is that you need to have access to someone who will be able to maintain your investment.

Maintenance can also be a concern when deciding between liquid-cooled and air-cooled engines. Usually, mechanics consider air-cooled engines easier to work on. They're less complex and have fewer parts. They?re also lighter in weight, less expensive, and perfectly suitable for the average mowing application. Penner calls air-cooled engines, 'the workhorses of the industry.'

However, if you're going to be running your mower day-in and day-out with extended hours, or if you'll be operating in an extremely warm climate, a liquid-cooled engine is probably the way to go. These engines cool themselves more effectively than air-cooled engines. This consistent operating temperature can lead to increased fuel efficiency, and give the engine a longer life.

9_2.jpgOther individual features have been added to engines to either decrease maintenance or make maintenance easier; either can mean less downtime for your mower. For example, some manufacturers offer heavy-duty air filters either standard or as an option. These filters extend maintenance intervals, because they don't need to be changed as often.

Of course, features aside, the real key to having a mower that spends its time in the field and not the shop is preventative maintenance. Catching small problems early before they become big problems can save hours of downtime, and much of the preventative maintenance required takes only a few minutes.

Some recommended preventative maintenance tasks are to check the engine oil, inspect for oil and fuel line leaks, clean the engine and fins to allow air circulation, and check and tighten the mounting bolts. Manufacturers will give you guidelines for oil and filter changes; these are important to keep track of as well.

Simon Corado, foreman for Cagwin & Dorward Landscape Contractors, Novato, California, takes pride in how long the operating lives typically are for his company's mowers. The company has created its own maintenance schedule to follow; in some ways, it is even more rigorous than what manufacturers may call for.

"All of our mowers go through mandatory routine maintenance every 50 hours," he says. "We change the oil, check for damage, and basically make sure that everything is working as it should. We expect our mowers to be available to us when we need them, and not in the shop, broken down. Because of our maintenance schedule, they're usually ready to go."

If you purchase an engine with the right amount of power for your application, and maintain that engine as required, it's a good way to assure yourself that your mower, too, will always be ready to go.