Automotive Charging Systems

By Charles Evans

Electricity is the life blood of the automobile. This has always been the case as nearly all gasoline internal combustion engines use electricity to ignite the fuel. Today the total automobile is controlled and operated by electricity and electronic equipment. This include fuel control, emission control, accessories such as the heater and air conditioning system, steering control, brakes, lights and many more. It is obvious that the charging system that provide this power is a very important system.

The charging system usually include a method to generate electricity and a battery to store the power. This sound pretty simple but it is no longer a simple system. The typical system consist of an alternator that is usually belt driven by the engine. The out put of this alternator must be regulated to control the voltage with in a specific range. The usual range is 12 volts to about 14.2 volts. If the voltage gets to high or too low electronic and electrical components will not work or they may be damaged.

Every alternator is controlled by some form of electronic regulator that controls the output of the alternator. In years past that was a regulator mounted to the vehicle independent of the alternator. A few years ago the regulator was moved into the alternator and the system was called internally regulated. A few manufactures decided that the electrical system should be interfaced with the computer network. Now most cars either control the charging system by computer or monitor it and set certain levels by using the engine control computer. Many systems reduce the alternator load during periods of hard acceleration.

Can I test and diagnose problems with my alternator? That depends upon the equipment that you have. A good multi meter will give a fair indication of the state of a charging system. If all that you have is a multi meter measure the voltage at the battery terminals before starting the engine. Then measure the voltage with the engine running at a fast idle. The resting voltage should be close to 12.6 volts and the operating voltage generally ranges 13.2 to 14.2 volts at the battery. You can also measure the output voltage at the alternator and it should measure with in 0.1 volts of the battery voltage. After measuring the voltage at a fast idle, turn on all of the accessories and the lights. The voltage should remain close to the same as at a fast idle (with in about 3 or 4 tenths of a volt).

A customer came in the other day and stated that one of the parts people at a national known auto parts store had told him that the only sure way to see if an alternator was working was to disconnect the negative battery cable and see if the engine continued to run, if it does the alternator is okay. DON'T EVER DISCONNECT A BATTERY CABLE IF THE ENGINE IS RUNNING.

Disconnecting a battery cable with the engine running will most likely damage your voltage regulator, engine management computer and other components. This could end up costing you thousands of dollars. For the same reason do not reverse the battery terminal when jump starting a car.

Can I change my own alternator? Yes if you have the correct tools. Get a good repair manual before you try to diagnose or change your alternator.

2 Way Car Alarms - Wave Of The Future

By David Faulkner

2 way car are alarms bringing automobile protection systems into the future. A car alarm is now so much more than just a loud ringing noise when the vehicle is invaded. A 2 way car alarm is now able notify you remotely via pager when the alarm is activated. They also provid the ability to start and control the car from a distance. These special alarms can do nearly everything short of driving the car for you!

The technology, often utilizing FM radio waves, is not endorsed by some law enforcement officials because of the fact that real-time notification of theft activity might turn some car owners into vigilantes. It is seen as a trade-off in citizen safety to have the ability to try to intervene in a theft in progress. However, the remote action options available with 2 way car alarms, including door locks and trunk release, have allowed some car owners to derail a theft from as much as 2,500 feet away.

Many 2 way alarm manufacturers build GPS systems into their alarm units, which is a valuable tool in recovery of stolen vehicles. The ability to track and pinpoint the location of a stolen vehicle has helped reunite many owners with their cars. However, the satellite technology used by these 2 way car alarms is far from foolproof since the signals only work when line-of-sight is possible. They can can be obstructed by solid objects including below ground parking facilities. Still, it's a great advance in fighting auto theft.

Beyond these security measures, some modern 2 way car alarm models offer very attractive comfort features to their owners. Imagine being able to keep your vehicle locked while remote starting the car and engaging the climate control. The days of waiting in the heat or cold until the car's temperature regulates can be a thing of the past with these fantastically user-friendly options!

Despite the incredible advances of these 2 way car alarms, it must be stated that they cannot upgrade a vehicle beyond its original capabilities. For example, when installed in a car that does not have automatic door locks or trunk releases, these features will not work regardless of the alarm system. Additionally, most 2 way car alarms are designed to work strictly with automatic transmission vehicles. A standard transmission cannot be started remotely as the transmission must be manually disengaged to be able to start. So, be sure that your vehicle is equipped to take on the many advantages of a 2 way car alarm system, and then enjoy this space-age gadget!

Car's Oil Can Be Changed Easily By You

By Juan Uflerbaumer

Changing your car's oil yourself is a lot easier than you think, and also you can save money.
Whether you are a first timer or experienced, this is a detailed guide to show you themost efficient and safest way to do this simple task, but remember, safety always comes first when it comes to automotive maintenance.

about 5 quarts of motor oil will be needed. (the proper SAE viscosity, API performance and quantity required for your engine as well as filter specs is in your owner's manual)

A new oil filter. This is a "spin-on" type oil filter, it comes in various sizes and shapes.

A drain plug socket wrench or open-end wrench (exact size) and an oil filter wrench.

A large drain pan and a rag.

Your motor oil and oil filter should be changed every 3,000 miles or every 3 months, whichever comes first. This will provide superior engine protection and longer engine life. (Check your owner's manual for special conditions and do not exceed warranty recommendations.)

Never use a jack to hold your vehicle up because it is too unstable. Wheel ramps are ideal and much safer. Drive your vehicle up onto the wheel ramps so that the front tires are elevated. Set your emergency brake and brace both rear wheels with wooden blocks. Put your vehicle in park if you have an automatic transmission and in first gear if you have a manual transmission.
Idle your engine for about 5-10 minutes to bring it to normal operating temperature because if the oil is cold will not drain properly (never start your engine without oil). Then switch off the engine and raise the hood to locate and loosen the oil sump cap to avoid vaccum, this will allow the oil to drain from the bottom more freely.

Locate the oil drain plug on the underside of your vehicle. It should be located at the bottom rear end of the engine sump.

Place the drain pan underneath the drain plug. Turn the plug counterclockwise using your wrench until it rotates freely. Finish removing the plug by hand. Be careful of the oil since it may release rapidly and is likely to be rather hot.

After that, loosen the oil filter - may be warm - turning it counterclockwise with a filter wrench. Complete the removal by hand, taking care not touch the hot exhaust manifold. The oil filter may feel slightly heavy because is filled with oil, so carefully ease it down and away from the engine and tip its contents into the drain pan.

Take your rag and wipe in and around the filter seat on the engine. Then take a new filter and carefully screw the new filter onto the threaded oil line, turning it clockwise. Once aligned properly, the filter will thread on easily. Tighten the filter by hand, taking care not to overtighten.
Clean the oil plug and drain set and then align and replace the plug. Screw the plug in by hand and finish by tightening it with a wrench. Take care to not overtighten.

You will find a cap that says "Oil" on the top of your engine. Unscrew the cap and proceed to fill the engine with the required quantity of oil, checking with the dipstick to assure proper fill level. Then replace the cap. The oil light should go out as soon as the engine is started. Run the engine for several minutes, then switch it off and check the dipstick once again to assure proper oil level. Last, check under the vehicle if there are leaks.

Car Theft

By Dennis J James

With all the advancement in auto anti-theft technology you would believe that the theft of vehicles would be less than ever before, however, that statement is farther from the truth than you can imagine. A matter of fact, automobile theft is still a booming business. All anti-theft systems can only do so much to aid against car theft.

The National Insurance Crime Bureau recently reported that the vehicle theft rate has risen to nearly 1,260 million vehicles an increase of 14,000 over the previous year. With this report, it shows that car thefts have increased consecutively over the last four years. They also provide suggestions to help every car owner protect their cars from thieves. Anti-theft systems cost quite a bit of money and many car insurance companies do give discounts on your insurance if you have some types of anti-theft devices on your car.

The NICB reported that the total loss for owners and insurance companies due to car theft is more than $8 billion a year, which is a figure that is getting larger each year as vehicles cost more and more. Auto theft costs all drivers with higher insurance rates.

The NICB also reports that where you live also plays a major factor. According to their report, owners living in a port city, an urban area in general, or a town, which is on the border with Mexico or Canada, should take into consideration some extra protection. The NICB lists the top 10 cities, including their surrounding areas, with the highest vehicle thefts from highest to lowest: Modesto, CA.; Phoenix-Mesa, AZ.; Stockton-Lodi, CA.; Las Vegas, NV.; Sacramento, CA.; Fresno, CA.; Oakland, CA.; Miami, FL; San Diego, CA.; and Detroit, MI.

The vehicle you drive even affects its chances of finding itself in the hands of auto thieves. The NICB listed the following vehicles as the most stolen vehicles in 2003 starting with the most stolen, the 2000 Honda Civic, 1989 Toyota Camry, 1991 Honda Accord, 1994 Chevrolet 1500 pickup, 1994 Dodge Caravan, 1997 Ford F-150 pickup, 1986 Toyota Truck, 1995 Acura Integra, 1987 Nissan Sentra and 1986 Oldsmobile Cutlass.

A few helpful tips for protecting your vehicles from car thieves include:

• Never leave your keys in your car; even if you think you have hidden them well, car thieves know all the hiding places.
• Never leave valuables in plain sight - this is too tempting.
• Never leave personal information in your car such as ID’s – this is just asking to become a victim of identity theft.
• Never leave the car title or registration in the car it makes it too easy to sale.
• Always park in well-lit areas.
• Most car thieves tow cars; always leave a standard vehicle in gear and with an automatic use your emergency brakes.
• If you put your car in the garage, lock all windows and doors in the garage.
• Do not believe your car is old so no thief would want it; age doesn’t stop a car thief.
• Even though, nothing can totally protect you against car thieves many could have been avoided with just a few precautions.

The 100 Year History Of The Hybrid Car

By T J Madigan

The history of hybrid cars is immersed in controversy. Not so much for the product itself, but for the technology it uses. Is it old like the conception of wheel itself, or is it a recent idea, as recent as the embryonic stem cell technology?

First of all, a hybrid car is a vehicle that uses on-board RESS, or rechargeable energy storage system. This is coupled with a fueled propulsion power source for the automobiles propulsion. The Hybrid car is a low-gas consuming vehicle, therefore, a low-polluting vehicle.

The last characteristic is particularly important because of the growing consciousness of people worldwide on the need to protect the environment.

History points to the clear differences between hybrid and all-electric cars. Electric cars use batteries charged by an external source. On this note, almost all hybrids, save for those considered as mild-hybrid, still need gasoline or diesel as their fuel source. Other fuels are also available in the form of ethanol or other plant based oils. Hybrid vehicles also use hydrogen gas occasionally.

What is the history of hybrid cars?

The history of hybrid cars is closely intertwined with the history of the automobile itself. In 1898, Ferdinand Porsche, a young Czechoslovakian, designed the Lohner-Porsche carriage, a series-hybrid vehicle that utilized a one-cylinder gasoline internal combustion engine. This engine spun a generator which powered four wheel-mounted electric motors.

The car was eventually presented at the 1900 World Exhibition in Paris. The said automobile, capable of up to 56 km/h (35 mph) fast destroyed several Austrian speed records. In 1901, it won the Exelberg Rally, with Porsche himself driving the car. Mass production during this time was yet to be developed, but for Porsches future-looking design, 300 units of this model were sold to the public.

The first Porsche model however, technically speaking as we know Porsch today, was a hand-built aluminum prototype, and was completed on June 8, 1948.

The development of the first transistor-based electric car in 1959, the Henney Kilowatt, heralded a new development in the history of automobiles as a whole, and the history of hybrid cars in particular. This transistor-based electric car, paved the way for the electronic speed control. Ultimately, this made the road for the development of modern hybrid electric cars possible.

The Henney Kilowatt was considered the first modern electric car. It was a product of collaborative work between the National Union Electric Company, Henney Coachworks, Renault, and the Eureka Williams Company. Whilst the sales of the Kilowatt during this time were far from encouraging, its development served as the prototype for the other automobiles down the line of hybrid cars.

Between the 1960s and 1970s, another prototype of the earlier electric-hybrid vehicle was built by Victor Wouk. Wouk is among the scientists involved with the development of the Henney Kilowatt automobile. For this work, some historians bestowed upon him the honor being the Godfather of the Hybrid hybrid car.

For his pioneering work, Wouk installed a sample electric-hybrid drivetrain into a 1972 Buick Skylark, courtesy GM for the 1970 Federal Clean Car Incentive Program. The program was later axed by the EPA in 1976. Hybrid enthusiast and supporters continued building hybrid automobiles. These models however, were not put into mass production.

In the fading years of the twentieth century however, the history of hybrid cars has taken on a new course.

1978, the regenerative-braking hybrid, was developed by Electrical Engineer David Arthurs. The said regenerative-braking is to have become the core design concept of most hybrids, currently available in the market. The first attempt of Arthurs used off-the shelf components, including an Opel GT. But the voltage controller that links to the battery motor and the DC generator belonged to Arthurs.

Fast forward in the 1990s

The history of hybrid cars took the final step to modernity in terms of mass production during the Bill Clinton administration. Clinton initiated the Partnership for a New Generation of Vehicles program in September, 1993, that involved the Department of Energy, Chrysler, Ford, General Motors, USCAR, and various governmental agencies. The partnership was tasked to engineer a modern efficient and clean vehicle.

In 2001, this program was replaced George W. Bushs own hydrogen focused FreedomCAR initiative. The focus of the FreedomCAR initiative was to fund research that is considered high risk for the private sector to engage in. The long term purpose of which is the development and production of petroleum emission.

The success of hybrid vehicles in terms of mass production however, became a reality, when the Japanese car manufacturer entered the American market. This is when the history of hybrid cars finally took its modern development. Honda Insight and Toyota Prius became the modern progenitor of modern day hybrid vehicle available today in the market.

What the Dealers Do Not Want You to Know

By Bryan Matik

So you want to buy a used car. It is scary, because there are so many places out there that offer used cars to you. But, you want the best price that you can find, so where do you look? Who do you turn to? Before you even begin shopping, it is important to do your homework. Check out your local classified ads to give you an idea of what the price of the make and model that you are looking for. Make sure to also look for Blue Book values in the high and low range so that you know approximately what the car is worth.

Another great source for those who are interested in purchasing used cars is CARFAX. This is a web based service that will supply you with a report on the vehicle’s history. All you have to do is provide a VIN number and whether the car was in an accident or had major work done to it, you will know. There is a program set up by the National Highway Traffic Safety Administration as well. It will tell you if there has been any recalls in the history of the car that you are going to purchase. It is also highly recommended to make sure that you have any vehicle that you are considering purchasing inspected by a trusted mechanic prior to buying the vehicle.

There are several places that you can look before going straight to a used car dealer. One of them is your local Classified Ads. You will see many, many cars priced at well below retail. When you take a car to the dealer for trade in, you are usually offered something well below wholesale price. A lot of people try to sell what they have without trading them in. This allows them to at least make several hundred more then what the dealer has to offer and you will not have to pay dealer prices.

Another great place to look is at Online Auctions. Online Auctions are a great place to find bargains. You do not have to go from dealer to dealer and look to see if they have what you want. In the comfort of your own home, you can look for auctions with no reserves and bid away. The only drawback is to make sure that the car is local; otherwise you will be paying some money to have to get your new used car if you win. The other thing that you need to be aware of is that you can put in the total amount that you are willing to pay and then just sit back and watch. You have to be patient. You may not get what you want the first few times.

Public car auctions are yet another great place to find used cars at cheaper prices. They are generally open to the public and do not require you to have dealer’s licenses. These types of auctions in general are an excellent place to buy cars at wholesale prices. There are a lot of different types of car auctions out there including: Auction Repossessions from banks and other credit companies, Police Auctions and Estate Auctions. Keep in mind though, that sometimes in Police Auctions that what you are buying might not be the whole thing. The car can sometimes be stripped out, but if you have the wherewithal to fix cars, then by all means, go for it. Most public auctions are advertised in the newspapers about 30 days prior to the auction. Make sure if you are going to attend on to go prepared to pay for your purchase in full.

New Care Dealerships

Okay, so you are wondering why the heck you would go to a new car dealership to get a used car. Well, it is simple, since new car buyers usually trade in their old cars; the dealerships always have an extensive amount of used cars to unload. The advantage here is that there is a wider range of makes and models to choose from. They also provide reconditioning to the vehicle before they resell them. Buyer beware though, they actually may attempt to persuade you to purchase more than what you actually are looking for. Make sure to have your game plan mapped out before going to a dealership.

Used Car Dealerships

You can find a used car dealer virtually on every corner of every town in the United States. They will sometimes be very tiny with only a small stock of cars, or they can be part of a dealership where there will be hundreds of used cars for sale. The difference between used and new car dealers is that the prices at used car dealerships is much less than if you were to purchase it at a new car dealer. Most used car dealers are much easier to bargain with when making your purchase. What you need to be aware of is that the quality of these cars is not as wonderful as those that you would purchase from a new car dealership. The selection may not be as wonderful either.

Car Auctions

In the past several years, there has been a big increase in public auctions as a way of purchasing cars and trucks. It used to be the auctions were only for licensed dealers. Fortunately for the benefit of the average Joe who is looking for a used vehicle, there are a lot of used car auctions that are open to the public. What you need to be aware of when it comes to auctions is that the selection and quality of the vehicles will vary. One week you may see top of the line vehicles and then the next nothing to write home about. The prices that you see at the auctions are substantially lower than at the dealerships. Just keep in mind, you see what you get. There is no chance for you to have the vehicle inspected before you purchase it and all sales are final. You also need to be aware that a bidding frenzy could occur. Just be careful when going to a car auction.

Private Seller

Buying a car from a private seller has its ups and downs. On the positive side, you will be able to talk to the owner and see how the car was actually cared for. You can also get a much more reasonable price because they are usually priced as per Blue Book values. On the downside, it can be a hassle to go from private owner to private owner to look at several different cars to determine which is better. This means that you would have to set up several different appointments and then if you don’t act quickly, they may sell to someone else. Buyer Beware: if you see someone with a bunch of cars for sale, they actually may be a dealer. Always ask to see the title and registration of the car. If it is a few days old, be very wary.

Biodiesel Testing - Quality and Purity Testing Increase Confidence And Assure Results

By Andrew Stratton

Biodiesel and biofuel production is growing at an ever growing rate as new production facilities appear across Europe, Asia, and the Americas every month. Manufacturers of biodiesel testing equipment are responding to these growing demands to supply the market at every level.

Biodiesel and biofuel production is growing at an exponentially increasing rate as new test-bed plants and full production facilities are being approved every month across Europe, Asia, and the Americas.

At present, biofuel production is considered experimental, and compared with other fuel production techniques, the total output is still very low. Feedstock supply lines are therefore quite limited, either being sourced from widely distributed waste products of other industries, or from niche crops like canola, a relatively new rapeseed cultivar. This creates a problem for both major and minor biodiesel producers, who have the daunting task of producing homogeneous, high quality fuel sourced from feedstock of varying and ultimately unknown purity and content. The market has responded to the demands of these new industries to supply quality assurance biodiesel testing equipment for every production scale.

Given the climbing public awareness of global warming and strains on global energy output, governments and corporations around the world are fronting the expense of rebates, research grants, and tax breaks for operators in industries which work towards reducing greenhouse gas emissions, making the concept of small, high-tech niche-industry start-ups economically viable. This has attracted big investment dollars in Brazil, the United States, and some members of the EU - most notable among these being Germany, where there are dozens of medium and large-scale alternative energy generation plants.

Biodiesel is defined as a diesel equivalent produced via transesterification of common fats and oils. There are three main avenues of supply of feedstock to biodiesel production plants. The first of these is dedicated crops grown specifically for their organic oils. Examples of these include soy beans, canola (rapeseed), oil palms, and algae. Canola and soy accounts for most of the total biodiesel production feedstock for the world, as it can be grown with conventional farming techniques, with predictable results.

The crop with the potential to produce the most oil is actually a species of algae, Botryococcus braunii, however, there remain serious doubts about its viability as a crop. Medium scale ventures prefer the waste by-products of other farming methods. The woody part of corn plants, left over wood pulp, and other biomass materials can be used as a substrate for biodiesel or ethanol producing bacteria. This supply is desirable for medium-scale producers as it results from otherwise less valuable by-products that can be obtained in reasonably large quantities.

Small-scale and hobbyist biodiesel producers are most likely to make use of waste vegetable oils and animal fats from cooking and commercial food production, as these are ubiquitous, but usually available only in smaller quantities, and hobby users are not likely to need any more raw feedstock than is necessary for a tank of fuel in their car every week. Furthermore, it is impractical for larger producers to collect kitchen waste in the same way an individual can, at least until demand grows enough for such infrastructure to be built.

Large scale producers have ongoing testing requirements for samples from billions of gallons biofuel every year. Due to the experimental nature of the industry, initial investment for such projects is quite expensive, however, due to the mostly uniform content of the feedstock crops used, large biodiesel production plants have run fairly reliably once established. For big biodiesel, the emphasis is on quality assurance: There are stringent requirements put on producers to keep levels of pollutants and various contaminants under tight control. Areas tested can include alcohol content, ester content, sulfur, heavy metal, and water quotas.

Additionally, biodiesel must exhibit certain physical characteristics like viscosity and flashpoint temperature. Small and medium scale producers have slightly different challenges to overcome, as they often do not sell their product, but rather, use it internally to power on-site farming machinery, or in the case of a hobbyist, the family sedan. The challenge here is not in producing product that meets stringent sales requirements (although it is desirable), but rather, ensuring that the higher number of relatively small batches are safe and uniform, so as not to produce content that damages the engines of machinery and equipment.

While this work can be done in-house, it is far more economically viable for producers to contract out as possible. Larger testing enterprises usually have of at least one HPLC (High Pressure Liquid Chromatography) machine or Gas Chromatograph, which are available for less than US$20,000, as well as all the appropriate glassware and apparatus to conduct titrations and other analytic procedures. At the hobby end of the market are self-contained biodiesel reaction vessel kits available for less than $500, and biodiesel testing kits for testing small quantities of product which can be sourced for less than $50.

With the growing public concern over the excess of atmospheric carbon, world peak oil production, and alternative energy solutions, biodiesel is beginning to look like an increasingly appealing stepping stone in between petroleum products and a completely clean implementation of energy storage, like hydrogen. Biodiesel testing requirements factor into the equation for small, medium, and large scale producers to ensure a supply of quality product.

How Can I Benefit from BioDiesel?

By Steve Dolan

If you have an interest in being environmentally friendly, then no doubt you're aware of the damage fossil fuels are doing to our environment. Not only that, but at some point they will run out. Add in the recent jump in gas prices, and it's hardly surprising that more people are talking about making their own biodiesel fuel. Although it sounds like a great idea, you need to consider a few points before going ahead and making your own biodiesel fuel.

What Is Biodiesel?

To start with, let's take a look at what biodiesel fuel actually is. At its most simple, biodiesel fuel is made from either vegetable oil, animal fat, or mixture of the two. It's a clean burning fuel that is made from renewable resources hence the name biodiesel.

Generally, biodiesel fuel is made from straight vegetable oil, sometimes referred to as SVO. So if you want to make your own biodiesel fuel, you'll need to have an adequate supply of the basic ingredients. Unfortunately, most households don't produce enough waste animal fat or vegetable fat to come anywhere close to making enough biodiesel fuel to keep the family car running.

Using Recycled oil

This has led to a whole new industry, with the basic aim of sourcing much larger quantities of raw product. They get together with restaurants, bakeries, and any other business that uses a deep fryer, so that they can collect the used oil for recycling. The oils are then blended and used as the basis for biodiesel fuel. The processes are the same as you'd use to make biodiesel fuel at home, but by having access to a much larger supply of raw products, these companies can produce biodiesel in quantities that are more viable.

Can I make it at Home?

One thing to remember is that it's not quite this simple! Used vegetable oil needs to be mixed and stored, which can be quite a problem if you have large amounts of it. You also need to dewater, filter and deacidify the waste oil before it can be used for making biodiesel. This makes the production of biodiesel fuel at home a lot more complicated.

Having said that, it's certainly still quite possible to make biodiesel fuel at home, simply by buying straight vegetable oil, rather than using waste products. Even though it will cost you a lot more, when you compare it to the cost of buying the necessary amount of gas to run your car for a year, you can still save an enormous amount - somewhere around 75 percent. Even better, you're saving the environment too.

Can I mix it with Petroleum?

The short answer is yes! It can be blended with petroleum in any percentages and used as fuel. There is a fuel called B20 which is 20 percent biodiesel that has shown significant environmental benefits. It can be used in an existing diesel engine with either little or no modifications. The only thing to be aware of is that biodiesel acts as a solvent and can remove old deposits on on your fuel tank walls and your fuel lines. This may lead to a clogging of your filters so care should be taken. But hey - then you have a clean system!!

So if you're interested in saving money and helping out the environment, look at the option of making biodiesel fuel at home. It takes a little bit of effort, but the rewards are definitely worthwhile.

Brake Systems: Not an abstract theory

Brake operation is not abstract theory but a great example of applied science. We can look at brake troubleshooting from two engineering viewpoints-conversion of kinetic energy to thermal energy, and the application of hydraulic principles. Let's start with stopping power and then move to the hydraulic applications.


The power to stop a vehicle comes from converting kinetic energy to thermal energy. Kinetic and thermal energy are two sides of the same coin, which is heat transfer. The primary job of a brake system is to dissipate heat. In our rush to troubleshoot today's sophisticated braking systems, however, we often jump past basic heat transfer to the high-tech realm of electronic controllers and computer programs. In reality, the major factor that determines good or poor braking performance is simple friction.

The braking system exists to convert the energy of a vehicle in motion into thermal energy, more commonly referred to as heat. Friction is measured by its coefficient, which is calculated by dividing the force required to slide an object over a surface by the weight of the object. For example, if it takes 100 pounds of force to slide a 100-pound block of iron over a concrete floor, the coefficient of friction between the two materials is 1.0. If it takes only 2 pounds of force to slide a 100-pound block of ice over the same floor, the coefficient is only .02.

Friction exists at two points for each wheel during braking-between pad or shoe linings and rotors or drums, and between the tires and the road. These are the areas you want to think about when troubleshooting a braking problem.

Three factors affect the coefficient of friction in a brake system, and these involve some important service operations on your part:
• The surface finish of both friction surfaces.
• Temperature.
• The material-the metal of the rotors and drums and the friction material of the pad and shoe linings.

Manufacturers almost universally recommend against machining the surfaces of brand-new rotors and drums or refinishing rotors unless they're worn or scored beyond certain limits. All manufacturers do, however, specify definite surface finish requirements for rotors and drums.
Because contact between brake drums and shoe linings is linear, surface finish for a brake drum is not as critical as it is for rotors. The finish is not unimportant, however. That's why carmakers and parts suppliers tell you to make the final refinishing cut on a drum at a shallow depth and slow feed rate to ensure a uniform finish, free of grooves and spirals.