It’s no secret that purchasing quality equipment can save a contractor time and money. Not only does quality equipment reduce the amount spent on repairs but also the money lost due to lower productivity and rentals required to replace down machines. Not to mention the time spent coordinating repairs, obtaining replacement equipment and shifting jobs around as a result of broken machines.
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But how does one determine quality? One critical component of overall equipment performance is the engine. Because the engine plays an important role in the life of equipment, choosing the right combination of engine and equipment is critical. Be sure to consider the appropriate criteria for evaluating an engine.
Sizing Up Your Engine
One of the most important engine considerations is a good air cleaner. An efficient air cleaner will prevent dirt from entering the engine, reducing wear on the valves and rings. Dirt allowed into the engine will also get into the oil and cause additional wear on the connecting rod and crankshaft. An air cleaner with a dual element and small micron size should be selected to ensure optimum protection against dirt.
A dust-proof carburetor is also essential. A sealed carburetor that prevents dust from entering reduces damage that may be caused by a clogged air cleaner. Should the air cleaner become clogged, a sealed carburetor design becomes a must-have, back-up defense mechanism to prevent the damaging effects of dust. Without seals in place, dirt will get sucked through the gaps between the choke shaft and throttle shaft and increase wear on carburetor and engine components.
Another feature to look for is a cast iron cylinder liner. Most outdoor power equipment engine blocks are made from aluminum, a very soft material in contrast to the steel or chrome rings on the pistons. This variation in hardness causes the piston rings to quickly wear away the aluminum cylinder walls. As the cylinder walls wear down, compression is lost and ultimately the engine no longer produces enough power to properly run the equipment. Because cast iron is much harder than aluminum, cylinders with a cast iron lining wear much better in combination with the piston rings, leading to increased engine life.
Steel alloy components are another aspect to consider. Engines with items such as cam gears and cams made with cast iron last longer because the wear characteristics are much better than those of engines made with plastic components.
Ball bearing support of the crankshaft is also important. Because the ball bearings reduce friction, the power delivered to the crankshaft is increased. Additionally, a ball bearing support prevents problems caused by placing a crankshaft directly on an aluminum housing. Because aluminum is such a soft material, the crankshaft will wear away at the housing and eventually cause oil leaks during operation.
Finally, an engine should have a low oil sensor. If an operator allows the oil to drop below a safe range, a low oil sensor will ground out the ignition and stop the engine before damage occurs. This is vital since contractors are busy and often overlook basic maintenance items, like checking the oil.
Weighing Your Options
Not only does the initial selection of an engine greatly affect the overall performance of a piece of equipment, but deciding what to do after a problem occurs is also important. Once the life of an engine has ended, a contractor must often decide whether to replace or rebuild the engine.
Cost is the primary factor to consider when making the decision to replace or rebuild. The type of repair to be done, time required for the repairs, and parts and labors costs will all affect the final decision on whether to rebuild or replace a faulty engine.
Because of labor costs and the large amount of time usually required to rebuild an engine, replacement is usually the most economical choice for engines with less than 10-horsepower. Replacement also ensures another full warranty.
It also is usually suggested that the entire engine be replaced, as opposed to purchasing only a short block or a long block. Replacing the block alone requires the reuse of many parts from the old engine. Often the components being reused are worn out and also need to be rebuilt. Because rebuilding the various components is time intensive, purchasing an entire new engine may be less expensive.
However, if something happens to a newer engine where the majority of the parts are not damaged, simply replacing the block may be less expensive. For example, if an operator ran a new engine without oil, the majority of the parts will typically still be in good condition and a new block may be the most economical option.
Getting It Right the Second Time Around
When replacing an engine, some will consider changing brands. This creates another challenge in ensuring engine and equipment quality. It’s often assumed that merely providing a specification number will provide adequate information about the most effective engine replacement.
But to ensure the best match, contractors should contact a dealer or manufacturer and discuss the current engine’s features, along with the functions of the equipment that the engine will be powering. When providing the dealer or manufacturer with engine information, include details about items like the fuel tank and muffler size in addition to the specification number.
Consider also whether the new engine has the aforementioned key features, such as a good air cleaner and low oil sensor. Regardless of whether or not the engine being replaced has these features, they should be discussed with the dealer or manufacturer and included on the new engine to provide superior durability and quality.
Contractors often have to purchase a variety of equipment with different quality standards. However, the engine is one critical component that most equipment shares. With a solid understanding of the features that indicate a quality engine, contractors can make better decisions about the equipment they purchase. Regardless of the equipment’s purpose, having a quality engine is one way to ensure a piece of durable equipment will provide a long life of service.