Tire Tips and repair

    tireTires are far more important to your car than you may think. To a great extent, they control stopping, starting, turning, and smoothness of ride. They even make a great impact on you gas mileage. There are tires for every purpose. I strongly recommend using the proper tire to match the weather conditions and their use.Auto Insurance Companies, Governments and Industry are taking notice in the importance of tire safety involving accidents. In fact, Governments are starting to legislate laws, that require snow tires in the winter. If you ever driven in snow and ice you would know what I mean. In the last few years, Governments are looking into legislating installing electronic tire pressure monitors in the new vehicles. Tire pressure has a large relationship to tire failure especially at highway speeds.

    The quality of the tire makes a huge difference in your stopping power. Tires alone can account for a 25 percent difference in stopping distance. After the brakes is applied, tire friction against the road surface determines how far the car will slide before it stops.

    The development of the automobile has actually hinged on tire progress. The speed, power, and weight of modern cars would not be possible without adequate tires. At one time, a few hundred miles was a long life for a tire. Today, thousands of miles is normal.

    Modern rubber tires are more than just rubber with different compounds. They have a tough fabric and stiff steel reinforcement on the inside to give them strength. All of the tires components are put together on a drum vulcanizes or toughens the rubber into a solid mass that can resist pavement wear better than steel.

     

    The four basic parts of a tire

    Tread, body or casing, bead and cord are designed for specific purposes

    tire

    The tire Tread rubber consists mostly of synthetic rubber and hardeners such as sulfur and carbon black. The tires tread enables the tire to roll smoothly over the pavement and to resist damage from road hazards and most important, to grip a variety of road surfaces as firmly as possible. Tread designs vary. For instance, a tire that grips especially well on wet pavement may not be a good tire on a dry pavement. You can choose treads for all-around use, for wet- gripping, or for mud and snow and ice- gripping.

    The tire body or casing flexes as the tire rotates and supports the cars weight. It is also designed to resist abrasion, as from scuffing the curb. Of course, there is a limit to the punishment a tire can take
    Constant slamming into deep chuckholes and over curbs will ruin even a new tire; so will driving on a flat.

    The bead of a tire is a strip around each edge that is shaped to hold the tire tightly to the rim of the wheel, and thus prevent air from leaking out between it and the wheel flange. The bead is made of loops of steel wire, which keep it from stretching from pressure and from the centrifugal force of rotation.

    Body cords are folded around the beads. They are made of rayon, nylon, polyester, glass-fiber, or other material. Each has its advantages. Rayon-cord tires are noted for their low cost and good ride. Nylon-cord tires usually give a slightly harder ride especially for the first mile or two after the car has been parked but offer toughness and resistance to road damage. Polyester and glass-fiber are new tire fabrics that bear consideration. Even steel is coming into use as a tire cord material; you can guess the toughness and impact resistance it offers.

    Types of Tires

    Belted bias-ply. This type is similar to the bias ply, except that the under tread area is reinforced with relatively stretch- free belts of fiberglass or steel. Two to six of these belts run the circumference of the tire, restricting tread squirm. Thus, the tread of a belted bias-ply tire does not wear away as rapidly as that of a regular bias-ply tire. Belted bias-ply tires generally cost more than conventional bias-ply tires. They should be used in full sets, or at least in pairs across an axle.

    Bias-ply. A bias-ply tire has a body made of layers, or plies, of cords that run from one wire bead to the other at an angle to the circumference of the tire hence, the term bias-ply. There are either two or four plies in a typical tire. Alternate plies run at opposite angles to form a crisscross design. They are laid at cross angles between 300 and 38 to give rigidity to both sidewall and tread.

    Radial-ply. A radial-ply tire is belted, too. But instead of running on the bias, its body plies run from bead to bead at 90 to the tires circumference, much like the stripes around a zebra. That makes the tread rigid and the sidewall fiexib1e resulting in superior road-holding qualities.

    Radials also tend to give the longest wear but they are the most expensive type. Use radials only in sets of four. If you use rear-mounted snow tires in winter along with radials in front, buy radial snow tires. Mixing radials with non-radials is like wearing a tennis shoe on one foot and hiking boot on the other. You get different types of traction, which can be dangerous.

    Tire Profiles

    tire2

    A recent addition to tire designation is the series designation. Tires are called 60 Series, 70 Series, 78 Series, or 80 Series, depending on their profile, or cross-sectional shape. In a 70 Series tire, the side wall height, as measured from bead to tread, is 70 percent as much as its tread width. A 60 Series tire is lower and wider, while in a conventional (80 Series) street tire, sidewall height is about 83 percent of tread width. The higher the series number, the higher and narrower the tire profile. Because of differences in handling characteristics and in running radius, use 60 Series and 70 Series tires only in pairs on the same axle.

    Tire Sizes

    Tire sizes can be confusing because they change with each new development in tire design. The new, wide-profile tires have different size designations even though they fit the same rims. For example, a common pre-1965 original- equipment tire, the 6.70-15, has been replaced by a wider tire, the 7.75-15. The newer bias-ply and belted bias-ply wide- profile designations for that tire are F78-15 in 78 Series, F70-15 in 70 Series, and F60-15 in 60 Series. The radial ply designations for the same size tire are FR78-15 in 78 Series and FR7O-15 in 70 Series.

    Now, in the newest tire codes, there is another change. Lets check out this example: P255/60R15 102T

     

    tire sizes P Stands for passenger car tire 
    LT for light truck or SUV
    Commercial
    T Temporary (spare )
    255 Stands for Width,
    The width of the tire in millimeters from sidewall to sidewall. (section)
    60 Stands for Aspect Ratio: or Profile 
    The ratio of height to with ( this tires height is 60 percent of its width )
    The higher the number, the taller the tire
    R Stands for radial (its construction) B=belted bias D=diagonal bias
    15 Stands for Rim diameter in inches. This can be from 8″ to 28″ diameters.
    102 Stands for load index. Different numbers correspond to different max. loads. This tire is rated for 1874 lbs.
    Many tires has this written separately on the tire along with the load capacity.
    T Stands for Speed rating. This tire is rated for 118 mph. There are different letters representing different speeds. Most tires doesn’t have this any more.

     

    There are many different Specialized tires, like the run-flat tires that has different designation numbers.

    European systems are a little different. They put the speed rating in with the construction. ( 255/60HR15 )
    There are many other ratings like tread wear, traction, and temperature resistance. When it comes down to buying you should investigate the differences.

    Before switching to different-sized tires, check the auto manufacturers recommendations. Never use tires smaller than those specified for your car. Usually, though, you can move up one, or some times even two, sizes to improve tire life, handling, and load-carrying ability. However, in some cars wheel well clearances or rim sizes do not allow a larger size. Again, check all the dimensions on your car before changing.

    Never put two different size tires opposite each other on an axle. In the front, that would affect wheel alignment and could cause the car to drift to one side. In the rear, it would strain the differential gearing because the larger wheel would make fewer revolutions than the smaller one in covering the same distance.

    When you replace just one tire, get one the same size as the others. Pair it with the best of the three remaining tires and use both on the rear axle, where the better treads will help traction. When replacing two tires, pair the new ones on the rear axle. Put the next-best tires in front and use one of the poorer ones as a spare.

    New tires need to be broken in (even the new spare put on to replace a fiat). That means driving at no faster than 60 mph for the first 50 miles. Normal city driving is a good tire break-in. Break-in allows the complex elements of the tire to adjust gradually and function as an integral unit.

    Tire dealers are required to have charts showing such facts for all of their tires, including load-carrying capacities at various inflation pressures. A brochure containing the same information is supposed to be given to every new-tire buyer.

    The Rotation

    Individual tires may wear unevenly because each one does a different kind of work. Front wheels steer. Rear wheels drive. Tires next to the road edge may wear faster because of the cross-slope of the road.Auto and tire manufacturers ca11 for switching the positions of car tires about every 5,000 to 6000 miles to make them all wear evenly. But tire rotation has drawbacks. For one thing, it is a lot of work. Add the cost of balancing the tires after each rotation.The Rotation

    Perhaps worst of all, tire rotation may mask a misaligned front end, badly worn shock absorbers, or defective brakes. Such mechanical problems cause premature and uneven tire wear but you may rotate the tires before the uneven wear be comes obvious.

    Radial, belted bias-ply and studded winter tires should not be rotated. When they are taken off and stored, label them for remounting in their original wheel positions so they will roll in the same direction as during their first season. (Radial and belted bias and certainly directional tires must be switched from front to rear or rear to front, as long as they rotate in the same direction.)

    Tire Storage

    When storing any tire, lay it flat on a clean, dry, oil-free floor. Keep it away from electric motors. Sparking motors produce ozone, a form of oxygen that deteriorates rubber rapidly. And store it in the dark; sunshine is hard on tires. There are commercially made Racks available for home use, to those that are changing tires often. ( Summer to Winter ) Some come with covers to help keep them clean.

     

    CARE OF TIRES

    You will get more mileage and better service from your tires if you treat them right.
    Pressure. Most important, keep tires properly inflated.

    Too little pressure makes the tread scuff off at the shoulders or the outside. It also allows excessive flexing of the sidewall. That heats the tire body from inside and causes faster wear and even tire failure.

    Too much air pressure causes severe wear in the center of the tread. It also strains the tire body and makes it prone to damage by impact with road hazards.

    Your car owners manual should show a range of pressures, depending on the type of driving you do. There are pressure information on a sticker in most door jambs.

    Keep an accurate tire-pressure gauge in the car, and use it at least once a month to check pressures when the tires are cold. If adjusting pressures properly is a problem because you live more than a few miles from a place where you can get air, try the following: With your gauge, test one tire at home while it is cold, and make a note of its pressure. Then drive to the service station, and with the same pressure gauge, take another reading of the same tire. The difference between the two readings is the amount the pressure was increased by the warm up drive. Simply add that difference to the tire specifications and inflate the tires accordingly.

    For instance, say the trip to the station expands the air in the tire two psi. Add this difference to all your cold-pressure specs. If your manual calls for 23 psi in the rear and 26 psi in the front, fill the rear tires to 25 psi and the front tires to 28 psi.

    When the weather turns cold, tire pressures fall off, and must be boosted back up to the specified cold pressure to avoid run- fling under inflated. Every 100 temperature drop lowers the pressure about 1 psi.

    If you must check tire pressure when the tires are hot, such as after several miles of fast driving, never bleed air from the hot tires to bring their pressures to the cold specifications. Such pressure buildup is normal; bleeding the tires would leave them under inflated

    Tread. Check the tire treads often. Nails, small stones, and pieces of metal or glass embedded in the tread should be pried out. A tire that leaks should he removed and its inside inspected. Permanent re pairs should be done only from inside.

    Check regularly for tread wear. Tires that are worn below 1/16 inch tread depth are dangerous and should be taken out of service. Tires of recent make have built-in tread-wear indicators bars of solid rubber that appear across the tread when the tire has only 1/16 inch of tread remaining. When the tread-wear indicators contact the road in two or more adjacent tread grooves and in three intervals spaced about 1200 apart around the tires circumference, that tire should be replaced.

    Tires without tread indicators should be measured in two or more adjacent grooves and at three locations, about 120 apart, around the tire. You can gauge 1 easily with a Lincoln-head penny. Place the penny on edge in a groove, with the top of Lincons head pointing into the tread. If the top of the head is out of the groove in several spots around the tread, the tire needs replacing.

    For more precise measurements, buy a tread wear gauge (about $1). Such a device shows you which tires are wearing fastest, and whether the wear is even or spotty. If the front tires are wearing considerably faster than the rear ones, your car probably has a wheel alignment problem.

    Valves. Tire valves, valve cores, and ex tensions should be in good condition. Valve stems should have valve caps that are screwed on finger tight.

    You need at least one metal valve cap that is designed for removing and replacing valve cores. If the special cap cannot be on the valve stem, keep it in the glove compartment.

    About every other tire change, you should change the valve. Snap-in replacement valves for tubeless tires are carried by tire dealers and are lubricated so that you can pop them into the wheels valve opening. The replacement should match the original in length and in TR number (molded into the valve base).

    Whitewalls. Some whitewalls come from the factory with a colored protective coating on the white portion. That coating should be removed before you use the tires, since it is not as flexible as the rubber and tends to crack, causing the sidewalls to check. In no case should a whitewall be driven more than 50 miles without re moving the coating.

    To get it off, wet the tire surface thoroughly with warm water, let it soak for a minute, and then wash off the coating with a soft-bristle brush or a sponge. The coating can also be removed in a jet-spray car wash by close jetting. Never use gasoline or other petroleum solvents or a wire brush.

    Road dirt that collects on whitewalls should be removed only with soap or a nonabrasive cleaner and, when necessary, a soft-bristle brush. Oil-based cleaning fluids, gasoline and kerosene deteriorate the rubber and may discolor whitewalls.

    Winter (Snow) Tires

    Insurance companies and Governments are becoming aware of the importance on the use of snow tires. They give a shorter stopping distance and greater maneuverability, which in turn, reduces accidents and injuries.
    Winter tires 
    are a different breed. They are designed for a specific purpose, winter. They are designed for snow and ice, sometimes more of one than the other. Your best bet would be to check with your local dealer, what is available, to meet your needs.

    It is not only the snow you have to worry about, its the temperature drop. In, around 7 Degrees Celsius, most tire compounds become stiffer and doesn’t conform to road surfaces as well. This tells you, it would be a good idea to put on your winter tires.

    Winter tires are not only designed for these lower temperatures, they have the tread patterns most suited for snow and ice. They also has the rubber compounds and sipes for the job. Sipes are the little cuts in the tread pattern that helps deflect some of the water picked up. Winter-specific tires will outperform even the best all-season tires when the temperatures drop.

    Studded tires will help on ice but they can be very noisy. A lot of areas ban these on their roads except for special circumstances. They can tear up the payment among other things. They are recommended to install only after the snow flies.

    Winter tires usually have a mountain icon imprinted in the sidewall.

    Winter tires should be removed as soon as the weather clears up. The same compounds that give winter tires its advantage will heat up and wear prematurely in the summer. They will give a spongy feel to the drivability of the vehicle on dry pavement.

    I would recommend having a complete different set of steel rims with the snow tires on them and balanced. This can be a little pricey but you would save on mounting and balancing costs in the future. It would also save on some deterioration on your alloy wheels, if you have. Put some wheel covers on them steel rims to enhance the looks and protect the lug nuts of the wheel assembly.

    Automotive Troubleshooting

    The most inexpensive and easiest way to keep your vehicle operating properly is simply to check it over on a regular basis. This is the best to way spot individual problems before other component problems occur and compound the symptoms. When maintenance is ignored, over a period of time, multiple repairs usually become necessary. This makes diagnosing the symptoms more difficult than if they had been discovered individually during periodic checks.

    The emissions, fuel, ignition, and engine management systems are interrelated, a minor problem in one can have a ripple effect on others. These minor malfunctions among several systems can eventually lead to a breakdown which could have been avoided by a simple check and maintenance Procedures.

    To start trouble shooting is is best to start with the basics first. Check for any cracks or other damage to hoses, vacuum, fuel and air intakes. Is the belts, battery and fluids in good shape. An engine needs spark, fuel, compression and air. Determine where the problem might be related to these systems. Is the symptoms happens when the vehicle is cold, hot or when it is humid out. Determining the environment when these symptoms occur will often lead you where to look.

    Engine will not rotate when attempting to start Engine rotates but will not run
    1. Battery terminal connections loose or corroded 1. Fuel tank empty
    2. Battery discharged or faulty 2. Battery discharged ( engine rotates slowly )
    3. Automatic trans axle not completely engaged in park 3. Battery terminals connections loose or corroded
    4. Broken, loose or disconnected wiring in the starting circuit 4. Leaking fuel injectors, fuel pump, pressure regulator etc.
    5. Starter motor pinion jammed in flywheel ring gear 5. Fuel not reaching fuel injection system
    6. Starter solenoid faulty 6. Ignition components damp or damaged
    7. Starter motor faulty 7. Worn, faulty or incorrectly gapped spark plugs
    8. Ignition switch faulty 8. Broken, loose or disconnected wiring in the starting circuit
    9. Starter pinion or flywheel teeth worn or broken 9. Broken, loose or disconnected wires at the ignition coil or faulty coil
    10. Engine seized 10. Broken or stripped timing belt or chain

     

    Engine hard to start when cold Engine hard to start hot
    1. Battery discharged or low 1. Air filter clogged
    2. Malfunctioning fuel system 2. Fuel not reaching the fuel injection system
    3. Fuel injectors leaking 3. Mal functional engine control system
    4. Malfunctioning engine control system 4. Corroded battery connections ( ground! )

     

    Starter motor noisy or rough in engagement Engine starts but stops immediately
    1. Pinion or flywheel gear teeth worn or broken 1. Loose or faulty electrical connections at distributor, coil or alternator
    2. Starter motor mounting bolts loose or missing 2. Insufficient fuel reaching the fuel injectors
    3. Vacuum leak at the gasket between the intake plenum\fuel injection throttle body
    4. Malfunctioning engine control system

     

    Oil Puddle under Car Engine lobes while idling or idles erratically
    1. Oil Pan Gasket and/or oil pan drain bolt washer leaking 1. Vacuum leakage
    2. Oil pressure sending unit leaking 2. Leaking EGR valve
    3. Valve covers leaking 3. Air filter clogged
    4. Engine oil seals leaking 4. Fuel pump not delivering sufficient fuel to the fuel injection system
    5. Oil pump housing leaking 5. Leaking head gasket
    6. Timing chain/belt and/or sprockets worn
    7. Camshaft lobes worn
    8. malfunctioning engine control system
    Engine misses at idle speed Engine misses throughout driving speed range
    1. Spark plug worn or not gapped properly 1. Fuel filter clogged and/or impurities in the fuel system
    2. Faulty spark plug wires 2. Low fuel output at the injectors. injector defective
    3. Vacuum leaks 3. Faulty or incorrectly gapped spark plugs
    4. Uneven or low compression 4. Incorrect ignition timing
    5. Defective fuel injector 5. Spark plug wire defective
    6. Malfunctioning engine control system 6. Faulty engine control/emission system components
    7. Camshaft lobe or valve train component worn 7. Low or uneven cylinder compression pressures
    8. Weak or faulty ignition system
    9. Vacuum leak at the fuel injector throttle body, intake manifold, or vacuum hoses
    10. Camshaft lobe or valve train component worn

     

    Engine Stumbles on acceleration Engine surges while holding accelerator steady
    1. Spark plugs fouled 1. Intake air leak
    2. Fuel filter clogged 2. Malfunctioning Torque Converter Clutch/solenoid
    3. Malfunctioning fuel supply or fuel injection system 3. Malfunctioning fuel supply or fuel injection system
    4. Malfunctioning engine control system 4. Malfunctioning engine control system
    5. EVAP system leaking or malfunctioning 5. Contaminated or defective oxygen sensors
    6. Alternator output low or excessive 6. Malfunctioning EGR system
    Engine stalls Engine lacks power
    1. Accelerator cable linkage binding or sticking 1. Incorrect ignition system
    2. Idle air control system malfunctioning system 2. Faulty or incorrectly gapped spark plugs
    3. Fuel filter clogged and/or water and impurities in the fuel system 3. Faulty ignition coil
    4. Malfunctioning fuel supply or fuel injection system 4. Rear brakes binding
    5. Malfunctioning engine control system 5. Automatic transmission fluid level
    6. Malfunctioning EGR system 6. Malfunctioning fuel supply or fuel injection system
    7. Malfunctioning engine control system
    8. Low cylinder compression
    9. Restriction in the catalytic converter or exhaust system
    Engine Backfires Pinging or knocking engine sounds
    1. Emission control system not functioning properly 1. Incorrect grade of fuel
    2. Ignition timing incorrect 2. Fuel injection system faulty
    3. Faulty secondary ignition system; cracked spark plug insulator, faulty plug wires 3. Improper or damaged spark plugs
    4. Fuel injection system malfunction 4. Faulty or incorrect thermostat
    5. Vacuum leak at fuel injectors, intake manifold or vacuum hoses 5. low coolant levels
    6. EGR stuck open all the time 6. Knock sensor system faulty
    7. Malfunctioning control system 7. Vacuum leak
    8. EGR system not functioning properly
    9. Malfunctioning engine control system
    Engine runs with oil pressure light on Engine diesels after switching off
    1. Low oil level 1. Excessive engine operating temperature
    2. Short in wiring circuit 2. Idle speed to high
    3. Faulty oil pressure sender
    4. Worn engine bearings and/or oil pump

    Engine Electrical System Troubleshooting

    Battery will hold a charge Alternator light fails to go out
    1. Alternator drive belt defective or not tightened properly 1. Faulty alternator or charging circuit
    2. Battery electrolyte level low 2. Alternator discreet defective or out of adjustment
    3. Battery terminals loose or corroded 3. Alternator voltage regulator inoperative
    4. Alternator not charging properly
    5. Loose, broken or faulty wiring in the charging circuit
    6. Short in vehicle wiring
    7. Internally defective battery
    Alternator light fails to come on when key is turned on
    1. Warning light bulb defective
    2. Fault in the printed circuit, dash wiring or bulb holder

    Horns

    Horn do not work Horn is weak
    1. Bad Fuse 1. Faulty Ground at horn
    2. Loose, broken or faulty wiring in the horn circuit 2. Loose, broken or faulty wiring in the horn circuit
    3. Faulty horn relay 3. Weak power supply “check voltage”
    4. Faulty horn button 4. One or two horns defective
    5. Faulty horns “check with jumper wires” 5. Horn needs adjustment
    Horn won’t shut off
    1.Check for short circuit to ground
    2.Check for defective components – horn button, relay, horn

    Power Door Locks

    None of the power locks operate

    One power lock does not operate, but others
    1.Check for bad fuse 1. Loose, broken or faulty wiring
    2.Check for bad relay 2. Switch faulty
    3. Check lock master switch 3. Lock Solenoid faulty
    4. Loose, broken or faulty wiring

    on Power Locks

    Power Windows

    No Windows Operate
    One Window does not Operate
    1. Check the fuse 1. Loose, broken or faulty wiring
    2. Check power window relay 2. Check power window relay
    3. Check master lock out switch 3. Check window switch
    4. Loose, broken or faulty wiring 4. Check window reguator and motor
    5. Check switch controls 5. Check window channels for binding

    on Power windows

    Fuel System

    Excessive fuel consumption Fuel leakage and/or fuel odor
    1. Dirty or clogged air filter element 1. Leaking fuel feed or return line
    2. Restriction in the catalytic converter or exhaust system 2. Tank overfilled
    3. Emissions or engine control system not functioning properly 3. Evaporative canister filter clogged
    4. Fuel injection system malfunction 4. Fuel injection system malfunction
    5. Low tire pressure or incorrect tire size

    Cooling System

    Overheating Overcooling
    1. In sufficient coolant in system 1. Faulty thermostat
    2. Water pump drive belt defective or out of adjustment 2. Inaccurate temperature gauge sending unit
    3. Radiator core blocked or grille restricted
    4. Thermostat faulty
    5. Electric radiator fan inoperative or blades broken or cracked
    6. Radiator cap not maintaining proper pressure

    cooling trouble chart



    Coolant loss Poor coolant circulation
    1. Too much coolant in system 1. Inoperative water pump
    2. Coolant boiling away because of over heating 2. Restriction cooling system
    3. Internal or external leakage 3. Water pump drive belt defective
    4. Faulty radiator cap 4. Thermostat sticking
    External coolant leakage Internal coolant leakage
    1. Deteriorated/damaged hoses; loose clamps 1. Leaking cylinder head gasket
    2. Water pump seal defective 2. Cracked cylinder bore or cylinder head
    3. Leakage from radiator core or coolant reservoir bottle
    4. Engine drain or water jacket core plugs leaking

    Brakes

    Vehicle pulls to one side during braking Excessive brake pedal effort required to stop vehicle
    1. Incorrect tire pressures 1. Malfunctioning power brake booster
    2. Front end out of line 2. Partial system failure
    3. Front or rear tires not matched to one another 3. Excessively worn pads or shoes
    4. Restricted brake lines 4. Piston in caliper or wheel cylinder stuck or sluggish
    5. Malfunctioning brake caliper or drum brake assembly 5. Brake pads or shoes contaminated with oil or grease
    6. Loose suspension parts 6. New pads or shoes installed and not yet seated. It will take a while for the new material to seat against the disk or drum.
    7. Loose calipers
    8. Excessive wear brake shoe or pad material or disk/drum on one side
    Noise (high-pitch squeal when the brakes are applied) Brake roughness or chatter (pedal pulsates)
    1. Front disk pads worn out. The noise comes from the wear senor rubbing against the disc (does not apply to all vehicles) 1. Excessive lateral run out of brake disc
    2. Incorrectly installed new pads ( many require an anti squeal compound on the backing plates) 2. Rear brake drum out-of-round
    3. Uneven pad wear
    4. Defective disc
    Dragging brakes Grabbing or uneven braking action
    1. Incorrect adjustment of brake light switch 1. Malfunctioning of proportioning valve
    2. Master cylinder pistons not returning correctly 2. Malfunctioning of power brake booster unit
    3. Restricted brake lines or hoses 3. Binding brake pedal mechanism
    4. Incorrect parking brake adjustment 4. Brake fluid, grease or oil on brake pads or shoes
    5. Caliper piston sticking
    Excessive brake pedal travel Brake pedal feels spongy when depressed
    1. Partial brake system failure 1. Air in hydraulic lines
    2. Insufficient fluid in master cylinder 2. Master cylinder mounting bolts loose
    3. Air trapped in system 3. Master cylinder defective
    Brake pedal travels to floor with little resistance Parking brake does not hold
    1. Little or no fluid in the master cylinder reservoir caused by leaking caliper or wheel cylinder pistons 1. Parking brake linkage improperly adjusted
    2. Loose, damaged or disconnected brake lines

    Suspension and Steering System

    Vehicle pulls to one side Abnormal or excessive tire wear
    1. Mismatched or uneven tire 1. Wheel alignment
    2. Broken or sagging springs 2. Sagging or broken springs
    3. Wheels in need of alignment 3. Tire out of balance
    4. Front brake dragging 4. Worn strut damper
    5. Overloaded vehicle
    6. Tires not rotated regularly
    7. Tire pressure not correct
    Shimmy, shake or vibration Wheel makes a thumping noise
    1. Tire or wheel out of balance or out of round 1. Blister or bump on tire
    2. Loose or worn wheel bearings 2. Improper strut damper action
    3. Worn tie-rod ends
    4. Worn lower ball joints
    5. Excessive wheel run out
    6. Blister or bump on tire
    7. Steering gear mounting bolts loose
    Hard Steering Poor returnability of steering to center
    1. Lack of lubrication at ball joints, tie-rod ends and steering gear 1. Lack of lubrication at ball joints and tie-rod ends
    2. Front wheel alignment 2. Binding in ball joints
    3. Low tire pressure 3. Binding in steering column
    4. Power steering fluid low 4. Lack of lubricant in steering gear assembly
    5. Power steering pump or steering gear defective 5. Front wheels in need of alignment or front suspension components bent
    Abnormal noise at the front end Wander or poor steering stability
    1. Lack of lubrication at ball joints and tie rod ends 1. Mismatched or uneven tires
    2. Damaged strut mountings 2. Lack of lubrication at ball joints and tie rod ends
    3. Worn control arm bushings or tie rod ends 3. Worn strut assemblies
    4. Loose stabilizer bar 4. Loose stabilizer bar
    5. Loose wheel nuts 5. Broken or sagging springs
    6. Loose suspension bolts 6. Wheel alignment
    Excessive pitching and/or rolling around corners or during braking Suspension Bottoms
    1. Loose stabilizer bar 1. Overloaded vehicle
    2. Worn Strut dampers or mountings 2. Worn strut dampers
    3. Broken or sagging springs 3. Incorrect, broken or sagging springs
    4. Overloaded vehicle
    Cupped tires Excessive tire wear on outside edge
    1. Front wheel or rear wheel alignment 1. Inflation pressures incorrect
    2. Worn strut dampers 2. Excessive speed in turns
    3. Wheel bearings worn 3. Front end alignment incorrect
    4. Excessive tire or wheel run out 4. Suspension arm bent or twisted
    5. Worn ball joints
    Excessive tire wear on inside edge Tire tread worn in one place
    1. Inflation pressures incorrect 1. Tires out of balance
    2. Front end alignment incorrect 2. Damaged or buckled wheel
    3. Loose or damaged steering components 3. Defective tire
    Excessive play or looseness in steering system Rattling or clicking noise in steering gear
    1. Wheel bearings worn 1. Insufficient or improper lubricant in steering gear assembly
    2. Tie rod ends loose 2. Steering gear attachment loose
    3. Steering gear loose
    4. Worn or loose steering intermediate shaft

    The Cooling System

    cool flowWhen an engine runs, it creates massive amount of heat. The internal combustion temperatures often reach as high as 4500 degrees. The cooling system must prevent the engine from overheating—even if the out door temperature is 110, degrees in the shade. Without proper cooling, the engine would eventually burn and score its pistons, and warp or burn its valves and cylinder heads. Without its cooling system, the engine block would become a red-hot mass of molten metal. And excessive heat also can break down engine oil to the point where it fails to lubricate properly.

    It’s the job of the cooling system to maintain the engine at its most efficient operating temperature, at all engine speeds and under all engine loads/driving conditions.

    Paradoxically, the cooling system also keeps your engine warm. On a cold day, some engine parts might never warm to operating temperature without the cooling system. A cold engine is inefficient. Moreover, combustion gases leaking past the piston rings condense in the crank case, where they form acids and sludge that can be harmful to vital engine parts. Heat from the cooling system helps vaporize and eliminate those blow-by gases.

    Here is how a typical liquid cooling system works: A belt-driven centrifugal water pump circulates coolant—water plus antifreeze—through a water jacket that surrounds the engine’s combustion chambers. The coolant absorbs heat from the engine and then is pumped through the radiator.

    When the car is moving, outside air rushes through the grille and past the radiator cooling tubes and fins, drawing heat from the coolant. When the engine is idling or the car is moving slowly, a fan, powered by the engine through the fan belt/timing belt or electric fan assembly, provides a sufficient flow of air. Sometimes, the fan has a shroud to draw air through the radiator.

    A lot of people forget that it is air that actually does the cooling of the engine. The modern cooling system is designed to incorporates air flow dynamics in a more critical manner. The engine and its components are designed in a more temperature sensitive manner. Any changes to the air flow can create large changes to coolant temperatures. So, make sure that all the baffles and shrouds that was design for the vehicle are in place and unobstructed.

    A temperature-sensitive valve or thermostat, placed in the coolant outlet passage, controls the flow of engine coolant, provides fast engine warm-up and regulates coolant temperatures. When the coolant is cold, the valve remains closed. Because this prevents coolant from circulating through the radiator, the coolant in the engine circulates within the block and warms quickly. As coolant temperature rises, the valve opens to allow coolant flow into the radiator, where the heat is dissipated through the radiator walls to the surrounding air..

    Even when the thermostat is closed, the engine still needs swift circulation of coolant through its water jacket to prevent hot spots — small areas that get hotter than the surrounding metal. Coolant circulation is then passed through a bypass, sometimes a short length of hose from the thermostat housing to the water pump intake. Many modern engines has a built in bypass in the block assembly.

    When the car heater is turned on, it also works as a bypass circuit, tapping hot coolant from the top of the water jacket and feeding it back to the intake side of the water pump. The heater uses engine coolant heat to warm the incoming air; that is why it does not work well until the engine warms up. Air cooled engines uses a set of baffles to draw heat from the external part of the engine to warm the passenger compartment.

    As coolant is heated, it expands in volume. The use of a coolant recovery system permits this fluid expansion to overflow into the recovery reservoir. When the engine cools, the coolant contracts in volume and vacuum draws any that has overflowed into the bottle or reservoir back into the radiator. This assures that the radiator will not boil over, and so remain filled to capacity at all times, maintaining the specified level of cooling efficiency.

    cool system
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