Brening also suggests, "Just as we do in our cars, it's important to let the trowel motor idle in the morning before putting it on the concrete."
Weekly inspections emphasize a closer look at your trowel's bottom end. A bent spider arm ? the part of the trowel that holds the blades or pans ? can result in a swirling pattern or waviness to the finish. An experienced operator can recognize these problems during operation, but noticing these problems during a job can often be too late to fix them in time to save the slab without re-work. Most manufactures offer spider assemblies with adjustable arms. This allows you to compensate for a bent arm and ensure your blades are all working on the same plane.
Another maintenance item you should add to your weekly checklist concerns the drive belt. Rubber drive belts will disintegrate with heat. Make sure your trowel's belt is in good condition, and change it when you begin to notice wear. "A lot of people use third-party belts and usually that's not a problem, but with variable-speed trowels with a torque-compensating drive system those belts are very specific to the application, and you need an exact match," Halverson warns.
Monthly maintenance items take a step beyond your daily engine maintenance checks. In other words, while you're checking oil levels and air filters or coolant daily, you should plan on monthly replacement or cleaning. Be sure to examine your engine manufacturer's recommendations to determine the best engine maintenance schedule. Not all engines are the same ? air cooled engines will generally need more frequent oil changes than liquid cooled engines.
Because the concrete jobsite can be very demanding on an engine, with dust and the high demand placed on a trowel engine, leading engine manufacturers offer features that make trowel engine maintenance easier for contractors. Cyclonic air filter systems are designed to work in high-dust environments, and some models can be equipped with restriction indicators that allow you to see if the air filter is dirty or clogged. These systems, while improving the performance of the air filter, also require their own maintenance. "Many of these machines have a remote air cleaner ? a canister-type air cleaner connected to the engine by a hose ? so there are a couple joints, a couple hose clamps and a piece of rubber tubing there, all of which are potential leak points. Those things should be inspected regularly to make sure you're not short circuiting the air cleaner," says Andy Traxel, Engineering Manager with Briggs & Stratton Daihatsu, LLC.
Another engine feature designed for easy maintenance is an oil alert system, which notifies the operator if the engine oil level drops below a safe operating level.
Traxel says if you're concerned about maximizing efficiency and keeping maintenance costs down you might want to take your maintenance to the next level of sophistication, especially if you're running a fleet of trowels. "I think the way to be really sure of maintenance and care of a machine, and to avoid spending any more money than you have to on oil and filters and shop labor, is to have an oil analysis program going for your equipment," Traxel says. "I think if someone did some oil analysis every 50 hours on a couple of machines they would understand the trend for the degradation of the oil in the engine, and that would tell them what an appropriate service interval would be."
"It is always best to run the engine for two or three minutes to warm it up before changing the oil," says Joel Borowski, manager of distributor & service operations with Honda Engine Sales Group. "Warm oil drains better and faster, plus running it before changing the oil will help remove more of the debris that is suspended in the oil." Check your engine manufacturer's recommendations for oil type and weight.
When it comes to buying coolant for your engine, be sure to read the labels. With the number of coolant blends available on the market, you might think you're buying a blend when you're actually buying a straight coolant. And never think straight water is going to cut it for a hard-working trowel.