What is the Difference Between Asbestos and Non-Asbestos Gaskets One gasket type contains asbestos as a reinforcing fiber while the other does not. As a reinforcing fiber, asbestos is strong, can withstand high temperatures and chemical attack, and is relatively cheap compared to many other materials. The physical properties that make asbestos an excellent gasket [...]
What is the Best Way to Fix a Coolant Leak
What is the Best Way to Fix a Coolant Leak? Proper repair depends where the leak is. Coolant leaks often occur at the water pump shaft seal. Other leak points include radiator, heater cores, hoses, freeze plugs, and the engine itself. Small radiator leaks, as well as minor internal seepage inside the engine or past [...]
What Is Included In A Complete Brake Job?
A complete brake job should restore the vehicle’s brake system and braking performance to good-as-new condition. Anything less would be an incomplete brake job. Brake components that should be replaced will obviously depend upon the age, mileage and wear. There is no pat answer as to which items need replacing and which ones don’t. It’s [...]
What Do Variable Rate Springs Do?
These springs increase load carrying capacity (usually 1,000 to 1,500 pounds.) without increasing ride harshness. Heavy-duty replacement springs will also increase load carrying capacity, but their stiffer spring rate may make the ride too harsh for comfortable everyday driving. Consequently, variable rate springs are a better option for the customer who occasionally pulls a trailer, [...]
What Causes Spark Knock
What causes spark knock and how do you get rid of it? Drawing on left shows completion of normal combustion. Cutaway on right shows a detonating cylinder, where the last portion of the air/fuel mixture self-ignites and collides with the normal combustion front. Spark knock (detonation) is an erratic form of combustion that occurs when [...]
What Can Make An Engine Overheat
Overheating is caused by anything that leads to a loss of coolant, prevents the cooling system from getting rid of heat, or causes excess heat in the engine itself: Coolant leaks (water pump, radiator, heater core, hoses, freeze plugs, head gasket, engine internal). Weak radiator cap (does not hold rated pressure and allows coolant to [...]
What Are the Significant Causes Tire Wear
Uneven or accelerated tire wear can be caused by wheel misalignment, worn suspension and steering components, and/or improper tire inflation. The most critical alignment angle with respect to tire wear is toe. Camber is also important and can be affected by caster. Misalignment is usually caused by worn, loose or bent suspension and steering parts [...]
What Are the Rules For Replacing Catalytic Converters
In a closed loop emissions operation, pump air is injected downstream between reduction and oxidation catalysts when the engine is warm. Three-way catalytic converters contain both catalysts in a single housing, with an air inlet between the two converters.Original equipment converters on new cars and light trucks are currently covered by an eight year/80,000 mile [...]
What Are the Recommendations For Service Maintenance Schedules
It is best to follow the Severe Service maintenance schedules found in most new car owner’s manuals, with a few exceptions: Air filters need to be inspected regularly and replaced as often as needed, regardless of mileage or time. Dirty air filters can increase fuel consumption and exhaust emissions. Fuel filters should be replaced yearly [...]
Replacing Brake Linings
Replace semi-metallic brake linings with semi-metallics, nonasbestos organic (NAO) linings with nonasbestos, and asbestos linings with either asbestos or NAO. Asbestos linings should never be substituted for semi-metallics. Asbestos in such an application will wear too quickly and may not provide the stopping power necessary for safe braking. Semi-metallic linings are usually required on the [...]
Picking the Right Performance Cam
Choosing a performance cam is never easy because there are so many variables involved and so many cam grinds from which to choose. Finding the one that’s right for a given application requires some serious communication between you and your customer. First and foremost, the cam must match the application. The cam determines the engine’s [...]
What Are the New Rules for Selling R-12
Starting November 1992, sale of small 12-ounce cans of R-12 refrigerant will be restricted to certified professionals only. Some states have also passed "can ban" legislation of their own that outlaws or restricts the sale of the small cans to professionals as well as do-it-yourselfers. Check with state officials for what applies in your area. [...]
Valve Stems
NOTE:Most tire manufacturers suggest replacement of the valve stem anytime a new tire is installed. Condition Code Procedure Bent 1 Suggest replacement. Broken A Require replacement. Cut, but not leaking 1 Suggest replacement. Deteriorated (cracking, dry rot) 1 Suggest replacement. Leaking A Require repair or replacement. Missing C Require replacement. Threads damaged A Require repair [...]
U.S. Metal Stud Reg.
Survey Of States This update of a survey of U.S. metal-studded snow tire regulations in all 50 states and the District of Columbia was compiled by the Tire Industry Safety Council and American Automobile Association. The latest survey reveals the following: Thirty-three states and the District of Columbia set seasonal restrictions for metal-studded snow tire [...]
Turning New Rotors Or Drums
There are two conflicting points of view on this issue. Some manufacturers say it is not necessary because their drums and rotors are finished at the factory and come ready to install. Resurfacing is therefore totally unnecessary. Furthermore, it would reduce the thickness of the drum and rotor and consequently its overall service life. Others [...]
Tires
WARNING: These guidelines do not apply to split rims. Replacing Tires When replacing tires, it is suggested that the replacement tires match or exceed the OEM speed rating designation. If tires of different speed rating designations are mixed on the same vehicle, the tires may vary in handling characteristics. Do not mix different speed rating [...]
Tire Rotation
The front tires on most vehicles tend to wear out faster than the rear tires. This is due to the effects of steering the vehicle and the weight transfer that occurs during braking. To ensure that all four tires wear evenly, it is important to rotate them on a regular basis. Tire rotation helps maintain [...]
Should I Replace Individual CV Joints or Complete FWD Drive Shafts
Should I replace individual CV joints or complete FWD drive shafts In today’s market, you have to sell both. Some people only want to replace the individual joint if it is bad. Others find it easier and faster to replace the entire driveshaft assembly. The choice is theirs, not yours. All you should do is [...]
Replacing Brake Fluid
DOT 3 and DOT 4 brake fluid are glycol based and absorb moisture over time. Moisture contamination causes the fluid boiling point to drop (which could lead to fluid boil and brake fade during hard use). Moisture contamination also contributes to internal corrosion in the calipers, wheel cylinders, and steel brake lines. The reason for [...]
OBD II Malfunction Indicator Lamp
OBD II Malfunction Indicator Lamp (MIL) When the ignition switch is initially turned on and the engine is not running, the malfunction indicator lamp lights for a bulb check. While the engine is running, the MIL will light only if there is an emissions-related concern. The on board diagnostic (OBD) generation two (II) system continuously [...]