Borowski says if you're working with a trowel equipped with an air-cooled engine it's important to the engine's longevity that the machine is not operating in a confined area. "Cool air needs to be drawn in and hot air needs to have a clear path to exit the engine," Borowski explains. "Any restrictions to cool air getting to the engine or allowing the hot air to flow away from the engine will cause the engine to overheat. That can and will drastically shorten engine life."
In addition to routine maintenance, there are a few annual checks you'll want to add to your maintenance schedule. Again, based on your manufacturer's suggestion for annual use, which is typically considered 300 to 500 hours of use, these are items you may end up doing once a year or a few times a year.
One annual maintenance item is changing your gear box oil. "There's a lot of friction in these gear boxes and a little bit of wear on those gears. You want to get that metal out of there or it's going to accelerate wear inside the gear box," Halverson says.
You should also pull out your blade arms and ensure proper adjustment, plan on replacing belt drives at least once a year, and closely examine your trowel's blade-tilt mechanism.
With walk-behind trowels, Halverson suggests annual maintenance on the throttle cable. "Throttle cable maintenance is something people don't think about until it sticks on them and they can't throttle down. Especially in the north where it gets cold in the winter and contractors are pushing the season, all you need is a drop or two of water in the throttle cable and it can freeze up and the trowel won't throttle up or down." Halverson uses a synthetic grease in the throttle cable, which he says tends not to attract water as much as a petroleum-based oil can.
Choosing Quality Blades and Pans
Keeping your finishing trowel well maintained is only part of the equation when it comes to achieving a professional floor. You also need experienced operators and quality wear components, namely blades and pans.
Your operator or maintenance crew should be checking blades for wear every day and replacing as needed to ensure you're getting the best finish possible. "A contractor will need to change a blade when it starts to fray, when it's worn back enough that the contractor isn't getting a good finish," says Jeff Snyder, sales manager with Wagman Metal Products, a manufacturer of trowel blades, pans and brushes. You should change all blades at once.
Snyder points out another reason it's important to check blades daily. "Sometimes the blades themselves can help indicate some other issue that might be going on with a trowel. In other words, if a blade is not wearing uniformly, it could mean a trowel arm is bent or spider assembly has some wear or needs attention," he says.
When choosing a quality trowel blade or pan, Snyder says it all boils down to consistency with high-quality raw materials and workmanship. "Steel throughout itself can have some high or low spots. If it's not consistent, you can get uneven wear or wobble," he says. "You want steel that is flat and straight. The mounting brackets should be straight, and if they are drilled the spacing between the holes should be consistent."
A quality float pan will have a flange design, which will give the pan a slight dish for shock absorbency. This helps to avoid a situation where the pan can go concave and create suction where the pan meets the floor, which will slow down the trowel.
"With the float pans on riders, we suggest a contractor rotates the pans similar to rotating car tires," Snyder suggests. "That will give the operator more consistent wear and performance." Snyder says you should rotate those pans about mid-way through their expected life. ? RW
Trowel Safety Information at Your Fingertips
The Association of Equipment Manufacturers (AEM) offers "Concrete Power Trowels Safety Manual." This manual is designed for operators and maintenance personnel. It was written by members of AEM's Troweling Machine Manufacturer's Bureau (TMMB) and includes information contributed by the leading manufacturers in the trowel industry. You can purchase a copy through AEM's website at https://shop.aem.org/.