PetroCan_Part1_pp7-20 6/15/04 8:57 AM Page 7 Part I Technically Speaking In This Part ᮣ Learning where the rubber hits the road (tires) ᮣ Finding out what makes a battery tick ᮣ Discovering the mysteries behind fluids and lubricants ᮣ Uncovering the truth about vehicle visibility nderstanding the technical aspects of your motor vehicle Uis the first step to safety on the road. In this part, you get the tips you need to learn what makes your vehicle tick. Tires Tire maintenance Tires are key to vehicle performance. Tires not only contribute to drive quality and noise level, but also have a significant impact on steering, braking, traction, and fuel consumption. Always keep tires properly inflated as per the manufacturer’s instructions; cold weather causes the air in your tires to contract, making your tire pressure decrease one pound for every 5°C that the temperature drops. Underinflating tires will not increase traction. There is only one way to properly repair a tire, which is to use a plug and patch combination. Proper tire repairs are completed from the inside of the tire out, requiring the tire to be removed from the rim. Plug repairs done from the outside of the tire are not recommended and could be considered very dangerous. PetroCan_Part1_pp7-20 6/15/04 8:57 AM Page 8 8 Vehicle Maintenance For Dummies Damage to the sidewall cannot be repaired. Should you encounter such damage, you’ll need a new tire. Regular tire rotations extend the life and performance of your tires and are recommended every 10,000 kilometres or twice a year. Types of tires All-season As the name implies, all season tires were designed to perform well under most conditions throughout every season. Each brand of all-season tires is different in appearance, but in general are a compromise between the aggressive tread of a mud and snow tire, and the smooth tread of a highway touring tire. These tires will provide a smooth, quiet ride and save you time and money since you won’t have to change them every season. They perform well but are not the best under extreme driving conditions. High-performance Primarily found on high performance cars, these types of tires are noticeable at times by their low profile, but often only by the speed rating stamped on the side of the tire. They are rated for the speed at which they can consistently be driven safely. If your car came equipped with a high speed rated tire or you drive at sustained high speeds, you require tires equal to the task. Safety is the main advantage, while added cost is the disadvantage. Winter/Ice Tires Winter/Ice tires have seen a resurgence in popularity recently due to improvements in design. They are superior in traction to all season tires in ice and snow. If you’re driving conditions involve heavy snow, the aggressive tread of winter tires will help pull you through. If ice is a factor, ice tread compounds are designed to grip the road like tiny suction cups or sandpaper, depending on the design. Improved stopping distances and traction are the biggest advantages for using these tires, while seasonal tire changes and reduced wear characteristics are a down side. PetroCan_Part1_pp7-20 6/15/04 8:57 AM Page 9 Part I: Technically Speaking 9 Rain Tires Rain tires are tires that have a tread pattern designed to funnel water away from the face of the tire preventing hydroplaning during heavy rain. For people who experience these driving conditions consistently, the design of these tires helps keep them on the road. The disadvantages to using these tires are increased cost and some compromise in feel on when driving on dry pavement. Since all tires have some variation in design and application, always discuss your driving needs with your service provider to get the best tire for your needs. Tread depth Generally, we recommend replacing your tires when the tread depth is 5/32nds of an inch or less. As a guide for tire replacement, some tires contain “wear bars.” Wear bars are located in the 2 grooves of the tire tread, and show up when only /32 nds of an inch of tread is remaining. At this stage, your tires must be replaced. Tires worn beyond this stage are extremely dangerous. Tires should be inspected and the tread depth should be measured every time you take your vehicle in for service. Batteries A battery is formed when two chemically different plates, one positive and one negative, are divided by a separator and placed in a solution called electrolyte. The positive plate is made of lead that is coated with a lead dioxide paste (PbO2), and the negative plate is lead that is coated with a sponge lead paste (Pb). The electrolyte is a mixture of water and sulphuric acid. Several positive and negative plates, divided by separators, are grouped together and placed into a single cell of the battery. When electrolyte is added, the resulting chemical reaction will always create voltage. A typical automotive battery is approximately 2.1 volts per cell. Therefore, a typical 12-volt battery will contain six individual interconnected cells, with each cell containing a stack of alternating positive and negative plates divided by separators and filled with electrolyte. PetroCan_Part1_pp7-20 6/15/04 8:57 AM Page 10 10 Vehicle Maintenance For Dummies There are two types of lead-acid batteries: accessible and non-accessible, maintenance-free. The accessible type has removable vent caps, so electrolyte levels can be checked and water can be added if necessary. The maintenance-free type has sealed or no vent caps, so you can’t check electrolyte levels or add water. Nowadays, most vehicles use the non-accessible, maintenance- free batteries. Always wear safety glasses when working on or near batteries. So why did my battery die? Ask yourself which is worse for your vehicle’s battery, hot or cold weather. Believe it or not, it’s the summer heat that kills batteries, not winter cold. Heat speeds up any chemical reaction, and so extremely high temperatures cause a battery to age more quickly. In addition, under-hood operating temperatures are on the rise as engine manufacturers continue to push more and more power out of smaller engine sizes. Add this to stop-and-go traffic on superheated pavement and the electrical draw from air conditioning, and it’s not surprising a battery’s health will be affected. Often, damage done over the summer months doesn’t become apparent until the first cold snap, when more power is required to turn over the engine—leaving unsuspecting motorists stranded in the cold. That’s why it’s important to have your battery tested as part of your pre-winter tune-up. Before you decide to buy a new battery, have the battery charged and tested to ensure it meets the manufacturer’s minimum cold cranking amps (CCA; the number of amps provided to start your vehicle at –18°C). PetroCan_Part1_pp7-20 6/15/04 8:57 AM Page 11 Part I: Technically Speaking 11 Battery Charging Guide 6 Volt and 12 Volt Batteries Recommended rate and time for fully discharged condition (“flat discharged”) Rated Battery *Slow Charge Fast Charge Capacity (Reserve Minutes) 80 minutes or less 15 hours @ 3 amperes 2.5 hours @ 20 amperes 1.5 hours @ 30 amperes Above 80 21 hours @ 4 amperes 3.75 hours @ 20 amperes to 125 minutes** 1.5 hours @ 50 amperes Above 125 22 hours @ 5 amperes 5 hours @ 20 amperes to 170 minutes 2 hours @ 50 amperes Above 170 23 hours @ 6 amperes 7.5 hours @ 20 amperes to 250 minutes 3 hours @ 50 amperes Above 250 minutes 24 hours @ 10 amperes 6 hours @ 40 amperes 4 hours @ 60 amperes *Recommended over Fast Charge (With high rate/fast chargers, battery overheating and gassing is likely if the charger is left unattended too long.) **Most automotive passenger/light truck starting batteries have a reserve capacity in the 80-125 minute range. Never attempt to charge a frozen battery! To avoid an explosion, allow the battery to warm to 15.5°C before placing it on a charge. Lubricants & Fluids Lubricants and fluids are key to your vehicle’s performance. Take a look below and read about the different lubricants and fluids that are found in your vehicle and learn what they do and how they do it. PetroCan_Part1_pp7-20 6/15/04 8:57 AM Page 12 12 Vehicle Maintenance For Dummies Oils Engine oil The lifeblood of your engine, engine oil consists of various- weight mineral or synthetic oils combined with additives for engine protection. Oils may come in single or multi grades and meet various performance standards. Engine oil lubricates, cleans, and cools critical parts of the engine. Its job is primarily to stop all the metal surfaces in your engine from grinding together and tearing themselves apart. It also has to dissipate the heat generated from this friction and transfer the heat away from the combustion cycle. A good engine oil must be able to hold in suspension the dirty by-products of fuel combustion while cleaning the engine. All of these things must be done under tremendous heat and pressure, without succumbing to engine fatigue. Change the engine oil regularly to extend your engine’s life, and always change the oil filter when you’re changing the oil. Driveline oil Commonly known as gear oil, this oil is typically used in manual transmissions and axles. Its characteristics are different from those of engine oil, as it is thicker and carries a heavier grade.