Subscribe Today

September 01, 2001  |   Comments (0)   |   Post a comment

Preparing Your Fleet for Wintry Conditions

Good fleet maintenance depends on a thorough inspection routine and attention to several key bus parts, which can be modified or upgraded to perform better in snow or ice.

by Joey Campbell, Assistant Editor


SHARING TOOLS   | Email Print RSS

In many areas of the nation, the sweltering summer heat belies the harsh, cold reality of winter. The summer also tends to allow some slack in operation routines and vehicle maintenance. Vehicles in some regions require wholesale changes when the time comes to accommodate the shift in weather. As a fleet manager, one of your most imperative responsibilities is to prepare your school bus operation for the inclement conditions associated with the winter season. The first changes you make should be procedural and generally based on common sense. For instance, having your staff arrive a little earlier than usual will help guard against the delays weather often causes. These include the time it takes to warm the buses on cold mornings and the need to scrape snow or ice from hoods and windshields. Early-arriving drivers are also less likely to hurry and drive faster than road conditions permit. And of course, dressing to keep warm is a small, but infinitely important, measure for employee health and comfort. After completing the small and simple tasks, the next step is to evaluate your entire fleet for potential problems. It is never too early to start examining vehicle components and maintenance routines. Here are some important reminders to get your school bus fleet ready for winter driving. Inspect frequently
A simple inspection procedure can eliminate many road breakdowns. Winter weather speeds up the wear and tear on many bus parts. Keeping a close eye on these parts is your best defense against this deterioration. Benjamin Reiling, terminal manager for Scholastic Bus Corp. in Chenango Forks, N.Y., says it becomes more important to ensure you're getting optimum performance out of your buses during the winter. "We have a specific winter inspection routine where we check everything a little bit closer than the rest of the year," he says. When inspecting your buses, remember to check all fluid and fuel levels, tire pressure, belts, battery, shocks, springs, hoses and any part that might be a safety factor. Inspect your buses as often as possible. Most maintenance facilities have their own guidelines for how often each component is to be inspected. Still, if you are not sure what is a reasonable time between inspections, ask another operator. At the start of each winter, give each bus a new wax job. Wax will bond with paint and help protect your bus from the nasty winter elements. Practicing good preventive maintenance will save your operation a lot of money and a lot of frustration. Choose the right tires
Winter driving demands a maximum level of control and traction. To attain this, you should first invest in winter tires. Dedicated winter tires with a rugged tread design will help your vehicles gain traction in snow and ice. Reiling says his buses are outfitted with an "aggressive snow tire from the tail end of Octo-ber until about March or April." In the winter, school buses commonly run 22.5 radial tires with curb guards, deep tread and increased traction. Some of the most popular winter tires for buses are Goodyear's G143, G164 and G175 RTD models; Michelin's XZA, XZE and XZU; and Bridgestone's M725. These models are recommended for cold, snowy conditions. Additionally, for about half the cost of new tires, you can purchase retreads that are as reliable and have almost the same wear mileage. Bandag is a company that specializes in school bus tire retreads. It is equally important to check your tires often for tears, tread wear and air leaks. You should remember to keep your tire pressure to manufacturer specifications. Some maintenance managers believe in adding more pressure to tires, but there is no solid evidence that this will improve traction. Dan Swearingen, bus technician for the Lapuai (Idaho) School District, runs snow tires with a deeper tread on his buses. He says that you don't need to inflate or deflate them beyond specifications but should still keep an eye on tire pressure. "When the weather changes, I have to bring them up to the right pressure because the cold deflates them a little sometimes," he says. Increase tire traction
In many areas of the country, simply running an aggressive snow tire is not enough. In more extreme winter conditions — especially when accompanied by mountains — it is a great benefit to have some form of supplementary traction. The most common way to gain extra traction is to equip your buses with conventional tire chains. These chain configurations wrap around each individual tire for added grip and control. There are also products available that disperse gravel underneath tires for traction, and it is always a good idea to keep a bag of kitty litter handy to provide traction in an emergency. However, automatic tire chains provide a more convenient alternative to conventional tire chains and other traction products. Automatic tire chains attach to a school bus suspension and throw lengths of chain under the tires. They are remotely activated and deactivated with the flip of a dashboard switch. They are offered both as an OEM option and as a retrofit product. Javier Hernandez, technical support specialist for OnSpot of North America, an automatic tire chain maker in Stratford, Conn., says that there are multiple reasons to avoid conventional chains. "First of all, you are limited in speed, and second of all, they are dangerous. You could bust a link and tear up your fender walls," he says. He adds that the time it takes to put them on and take them off can be a major inconvenience. The primary manufacturers of automatic tire chains are OnSpot, Insta-Chain Inc. in Springville, Utah, and Rud Chain Inc. in Cedar Rapids, Iowa. Maintain brakes
"The most important thing to remember to keep your buses safe in winter is to check your brakes," says Kenny Ellens, lead mechanic for Hudsonville (Mich.) Public Schools. He says that his district looks at brakes every 2,000 miles and, if there's anything close to a problem, they change them. Make sure that your brakes are adjusted and well greased. Ellens recommends turning the wheel centers to make sure that the brakes are not corroding or sticking. It also helps to add brake line antifreeze to keep the brakes lubricated and ready for sub-freezing temperatures. Your best bet for brake safety is to have antilock brake systems (ABS) that help prevent skidding, locking and hydroplaning. The ABS enables drivers to brake and steer at the same time, lending added directional control to the driver. Because antilock braking is a relatively new technology on school buses, it is unrealistic to think that many fleets have a majority of their buses equipped with ABS. Gary Myers, a driver for DRL Transit in Halifax, Nova Scotia, Canada, advises drivers who are unfamiliar with ABS to simulate a panic stop with an empty bus on an empty road. With ABS, he says, "the brake pedal vibrates under your foot, and it can be disconcerting if you aren't ready for it." Ensure high visibility
Driver visibility is a major safety issue in extreme weather conditions. The windshield and accompanying wipers should be clear of snow, ice and condensation in order for drivers to see as well as possible. First, make sure you have all-season windshield washer fluid and keep it topped off. It is a good idea to clean your defroster cores and vents to allow maximum air passage. Myers says that after he gets the bus warm in the mornings, he opens four windows one notch each, allowing enough ventilation to keep the win-dows from steaming up. This lets him see better, he says, "and the kids don't write their names on the glass so it's much easier to keep clean." Remember to replace windshield wipers before every winter season. Be sure they are properly aligned and positioned or they can cause an unwanted smearing effect on the windshield. You may want to consider installing heated windshield wipers, which melt ice and snow from wiper blades and prevent wiper freeze-up. The most popular model — Thermoblade from Specialty Mfg. in Pineville, N.C. — has a continuous heater throughout the blade and frame and reaches up to 176 de-grees Fahrenheit. Another alternative is the use of radiant heating strips that heat the wipers through the windshield. Mirror Lite Co. in Rockwood, Mich., has made this tech-nology available with its Northwind Wiper Heater. The product consists of heating strips that adhere directly to the inside of the windshield opposite the parked wiper blades. The strips are heated with a 12-volt connection and quickly thaw the blades and the glass around them. "We've talked to drivers who complain of having to bash away at their windshield wipers with brooms on winter mornings trying to free them from ice dams at the bottom of the windshield. This product will save them from that frustration," says Paul Schmidt, who designed the product for Mirror Lite Co. Keep mirrors clear
Driver visibility is also affected by the condition of school bus mirrors. Rearview, crossover and interior mirrors all run the risk of becoming steamed up in the winter. This causes serious problems for driving and for loading and unloading students. Your first line of defense against foggy mirrors is to keep them clean. Have plenty of glass cleaner available on the bus for use on the mirrors and windows if necessary. Swearingen of Lapuai School District uses a product called Rain-X to help visibility on his windows and mirrors. "It causes water to bead up and fly off glass easier, and bugs don't get stuck to the windshield," he says. Still, the best way to keep your mirrors clear is by using heated mirror systems. Several companies manufacture these devices, which have heating actuators lined inside the mirrors. Rosco Inc. in Jamaica, N.Y., manufactures multiple school bus mirror designs and makes every model available with or without a heater spec'ed into it. Ben Englander, vice president of engineering for Rosco, says that these motorized heaters will defrost all mirrors within 10 minutes. He recommends checking them before every run. To test them, he says, "make sure there is not excessive debris and ice between the mirror and the mirror housing to allow freedom of movement." Sunlight can be another factor affecting a driver's ability to see clearly. Although winter sun is considerably lower, it can be amplified when it reflects off of snow and ice. Glare ice, as it is called, can be very dangerous. Advising your drivers to wear sunglasses will help, but the most effective way to combat glare is to install sun visors. Rosco makes a tinted acrylic sun visor that is mounted inside the school bus. Check fuel and fluids
During the winter, the durability of a school bus may depend on what you put under the hood. Oil, fuel, coolant and other fluids dictate the performance of each vehicle. Knowing your buses and what products to use in them is up to you, but there are some general guidelines worth noting. As is standard, engine oil should be changed every 3,000 miles, but it doesn't hurt to observe it more closely than you would at other times of the year. Oil has the tendency to deteriorate quickly in intense driving applications, which can be caused by snow and ice. Make sure to keep accurate mileage records be-tween oil changes. Consider using multi-viscosity oil to help counter the poor fuel mileage you will get from winter driving. As for fuel, you should use Number 1 or 2 diesel fuel, which burns hotter and keeps injectors clean. Reiling says he uses a 10,000-gallon fuel storage tank which runs down until it's empty and then gets filled up again. "When it gets cold, we buy mixed fuel and treat it to make it heavier for the temperature," he says. Many school bus maintenance managers advocate using diesel fuel additives to improve lubrication and stop fuel from waxing. There is no factual evidence, however, to substantiate the claims made by diesel additive supporters. Frank Bondarowicz, senior project development engineer for International Truck and Engine Corp. in Chicago, says that International does not endorse or recommend the use of additives or other chemicals designed to improve engine perform-ance. "There are no standards for such additives, and there is very little hard data on them, mainly testimonials," he says. "The best advice that I can give on additives is caveat emptor." If you decide to use chemically treated fuel, you may want to speak to someone who has experience dealing with additives. In most cases, today's engine technology will allow satisfactory performance levels even with the lowest quality fuels and lubricants. You should also remember to keep your fuel tank at least half full overnight so the fuel won't freeze. Keep a 50/50 percent water-coolant mixture to prevent the buildup of silica in your cooling system. Maintain a proper level of all essential fluids, such as transmission, steering, brake and washer fluid. Deficiencies or excesses in fluids can lead to unnecessary downtime. Cold Weather Preparation

  • Check batteries and charging system for startability.
  • Check for electrolyte levels and specific gravity (not possible on some maintenance-free-batteries).
  • Check battery cable terminals for tight, corrosion-free connections.
  • Check alternator output voltage.
  • Check coolant freeze protection level. If the protection level is low, damage can occur to the radiator and loosen plugs.
  • "Dry run" your heating system to make sure heaters and blowers are working properly.
  • Three 600 cold cranking amps (CCA) batteries are better than two 900 CCA batteries for school bus application. The 600 CCA batteries contain more acid to hold a charge longer and return to full charge quicker than the 900 CCA batteries. Cold Weather Operation
  • Use Number 1 or blended 1 to 2 diesel fuel, which is less likely to wax in cold weather.
  • Keep fuel tanks full to reduce condensation.
  • Avoid unnecessary engine idle to save fuel and extend engine life. If the bus is to be idled for over five minutes, set the electronic control to 1,100 RPM.
  • Reduce coolant leaks by using constant torque clamps.
  • Use block/oil pan heaters for easier start and warm-up.

  • Post a Comment

    Read more about: brakes, mirrors, preventive maintenance, tires/wheels

    Request More Info about this product/service/company

    Post a comment





    Related Stories

    Premium Member

    Get bus sales numbers, transportation statistics, bus specifications, industry survey results, bus loading and unloading fatality statistics and more in the School Bus Fleet Research Center. Become a premium member today!
    Log in Button Register Button

    Newsletter

    Get breaking news, industry updates, product announcements and more.