With a bevy of attachments at its side, a compact utility loader can perform a wide variety of jobs on a worksite. Also known as mini skid steers and mini track loaders, these machines are built as hydraulic power plants meant to operate more than 70 categories of attachments, from buckets to augers, pallet forks to cold planers, hammers to trenchers, and, well, you get the point.

If a compact utility loader is going to be a go-to tool, the proper engine is an important consideration. Something has to do the work, or all those tool attachments are just useless ornaments. The attachments may make the machine, but the engine makes the machine go.

Whether it’s a diesel or a gasoline engine, the choice between the two could mean the difference between a cheaper buy and a more durable workhorse. It comes down to value, what fits with your fleet and the rigors of the job you want the machine to perform.

Compact utility loaders come in a variety of sizes, with hydraulics from 6 gallons per minute (gpm) up to 15 gpm. The power plants for these tool carriers can range from
13 hp up to 31 hp, depending on size and type.

The main difference between diesels and gas-powered engines is how the fuel is ignited. Diesels compress air into the engine cylinder, where it reaches a temperature hot enough to ignite the fuel to drive the piston. This process is called compression ignition, whereas gas engines use spark ignition. Gas engines compress both air and fuel in the cylinder and employ a spark plug to ignite the fuel. Diesel engines require higher compression and combustion levels, which requires the engines to be larger and made of heavier duty materials than gasoline engines.

Although the process is different, the end result is power to drive the machine’s components. For a compact utility loader, that boils down to the wheels or tracks and the hydraulic pumps. Each engine has its benefits and drawbacks, but with a little bit of research, making the right choice for your fleet should not be too difficult.

Perhaps the first consideration should be what type of engine would suit your fleet, says Matthew Naylor, a Ramrod mini skid steer engineer for Leon’s Mfg. Co. Inc., maker of the Ramrod Taskmasters. Most users want to keep their fuel standardized. If you have an all gasoline engine fleet, it may not make sense to go out and buy a diesel engine compact utility loader. Then again, it always depends on the applications and the amount of work for which you plan on using themachine.

“If it’s going to be a real workhorse, day in and day out, I’d look at getting a diesel,” Naylor says. “If I was doing a lot of indoor work, I’d also go with a diesel because of the [emissions] purification issues.” Ramrod offers four models of its Taskmaster line, varying from 22 to 27 hp on both wheeled and tracked designs.

Diesel engines, although emitting a more irritating and noxious smoke, burn cleaner than gasoline engines, Naylor says. The fuel is more pure and the engine burns more efficiently, reducing poisonous carbon monoxide emissions and increasing fuel economy.

Diesels have a reputation of being more durable for the long haul. Not only are the engines physically heftier, but most diesels also maintain a more even temperature because of a liquid cooling system, Naylor says. That is not to say that some gasoline engines are not liquid cooled. Some are, but those tend to come at a cost premium, which run between $500 and $1,000 depending on the supplier. However, for the added circulation a liquid cooling system provides, it might be worth the investment.

“Liquid-cooled engines are better than air-cooled because they have a radiator on it,” Naylor says. “They’re better for hotter climates and high power applications.” Applications such as trenching, when the engine is working its hardest, require a good cooling system to prevent overheating and long-term deterioration. Ramrod has moved away from air-cooled engines on its compact utility loaders, offering the option only on its 905 Series, which employs a gasoline-powered, 23-hp Kawasaki engine.

BACK TO TOP

The main advantage of the diesel is its ability to provide more consistent power during operation, says David Campbell, Ditch Witch design team manager of engines and operator systems. Diesels experience more torque rise than a gasoline engine when engine speed decreases because of the load. Therefore the power curve is flatter, allowing the machine to be more productive throughout its operation.

The biggest drawback of the diesel engine, however, is its cost on the market. Depending on the manufacturer, a diesel engine costs approximately $3,000 more than a gasoline engine. You’re definitely paying for any benefits the engine offers.
“Gas offers performance at a reasonable price,” Naylor says. “It’s a matter of do you want to spend the money up front or later?” Although the gas engine is cheaper to purchase or replace, it’s more expensive to operate because of its lower fuel efficiency. However, with the $3,000 saved at the time of purchase, Naylor says, “you can buy a lot of gas with that.”

Gasoline engines also tend to be more user-friendly, Toro technical services representative Dan Roberts says. The fuel is more readily available than diesel. “Every station has gas,” he says. “Not every one has diesel.” Diesels also use glow plugs, a feature not every operator is familiar with. Glow plugs help heat a diesel engine prior to ignition so it starts better, especially in cold weather. More people are just more familiar with using gasoline, which makes the engines more popular at rental yards.

The lighter weight of a gasoline engine can also be an asset, depending on the application, Roberts says. Gasoline engines tend to be built from lighter and less expensive metals, such as aluminum, because the combustion levels are much lower than diesels. Gasoline engines may be better suited for applications on soft turf, where a heavy diesel could tear up the ground.

The choice between a gasoline and diesel ultimately comes down to the customers’ specific needs, Roberts says.

“We have different units because peoplehave different needs,” he says.

Depending on the attachments they’re using, [Toro has] what people need to do the job. That’s why we offer different engine sizes to try to fit those needs.” Toro’s Dingo line offers a range of engines from 13 to 25 hp on wheeled or tracked models.

BACK TO TOP

Engine Upkeep
Once the choice has been made, there are some things you need to do to ensure your engine’s long life. The name of the game is maintenance. You want to follow the manufacturer’s manual, but there are some areas that many owners tend to neglect.

Aside from belt and hose inspection and daily fluid checks — oil, fuel and coolant — operators should also check the air filter on a regular basis to make sure it is clean, especially if the majority of work has been performed in dusty conditions.

Oil change intervals vary between diesels and gasoline engines. Gas engine oil should be changed about every 50 hours, Campbell says. Diesel engine oil should be changed after approximately 200 hours. That difference is mainly caused by the fact that diesel engines hold four to five times more oil than gasoline engines.

Knowing a little about troubleshooting also will help extend an engine’s life. The first indicator of a problem is the exhaust, Roberts says. Blue smoke indicates an oil usage problem. Black smoke can mean a fouling in the engine or an air restriction. White smoke in diesels might be the result of antifreeze leaking into the engine chamber.

Other common problems include: loss of power, commonly caused by a clogged fuel or air filter; overheating, which indicates a cooling system problem; and hard starting and running rough, both of which can be caused by problems with the fuel supply, water in the fuel, clogged filters or the ignition system.

Most engine problems stem from poor maintenance practices, Campbell says. So make sure you keep up with the manufacturer’s recommended intervals and keep that compact utility loader running strong.

Bradley Kramer is an editorial assistant of Compact Equipment.

BACK TO TOP