So Fix it

When a head gasket fails, coolant begins to leak into the crankcase and mixes with the engine oil. This mixture creates a milky-like substance that will coat anything and everything it touches. Coolant will ruin the crankshaft and connecting rod bearings, and the milky remnants of the mixture will clog oil passages, causing precisely oiled components to fail. In most cases, a blown head gasket can be prevented if the driver knows what leads to head gasket failure.

Overheating

Overheating is the No. 1 cause of head gasket failure. When the engine overheats, the engine head and block will expand and can crush the head gasket, creating an immediate leak. Even if the engine doesnt get hot enough to warp the cylinder head, excessive operation at high temperatures can cause the material on the gasket to become brittle and crack, creating a number of leaks.

Preignition

Preignition puts serious strain on the head gasket and is commonly associated with an overheating engine. Preignition occurs when hot spots develop within the combustion chamber, which become a source for ignition. When this happens, combustion will occur before the spark plug actually fires. The force created by the premature combustion puts undo stress on the head gasket and over time will cause it to fail.

Detonation

Detonation, also known as spark knock, is essentially improper combustion. When this happens, multiple flames are created inside the combustion chamber instead of one, causing a sudden spike in pressure within the combustion chamber. This extra pressure causes excessive stress to the head gasket as well as the pistons, valves and piston-connecting rods and is accompanied by a pinging noise during acceleration. Detonation is commonly caused by fuel with a low octane rating, a problem within the exhaust gas recirculation system and over-advanced spark timing.

Improper Cylinder Head Installation

If major engine work was recently performed and the cylinder head had to be removed, it is possible the mechanic doing the work failed to torque the head bolts properly or failed to torque the head bolts in the proper sequence during installation. Head gaskets require a certain amount of pressure to be maintained between the cylinder head and the engine block to load and keep a good and tight permanent seal.

Preventative Measures

Always keep an eye on the temperature gauge. Any time overheating begins to occur, shut the engine down, and diagnose and repair the problem. If you notice spark knock or pinging while driving, increase the octane rating of your fuel and check the exhaust gas recirculation system for faults. On older cars, adjust your air-to-fuel ratio accordingly. It is also very important to keep up on the maintenance of the engine ignition system; if your vehicle uses a distributor system, replace the cap and rotor according to the manufacturers maintenance schedule and always replace your plugs and wires every 15,000 miles or so for optimal performance.

CV joints, or constant velocity joints, help keep all of a cars wheels rolling at the same speed while also helping the suspension adjust to vertical movements. While most CV joints last for many years, a failed CV joint may require replacing an entire drive shaft, according to Samarins, a website useful to people in the used-car market.

Structure

A CV joint consists of a ball-and-socket joint with metal bearings packed in grease and surrounded by a protective rubber boot, according to 2 Car Pros. Each drive shaft includes inner and outer CV joints attached to each end of the shaft. Failure of either joint can lead to serious problems.

Damage

A CV joint becomes vulnerable to failure when the rubber CV boot covering the joint develops a tear. The torn CV boot allows grease to leak out from the bearings in the joint while also allowing grit to enter. Eventually the corroded joint breaks, ruining the entire drive shaft.

Trouble Signs

Diagnosing a CV joint problem early can help prevent total failure of the CV joint. Drivers who hear a clicking or knocking noise when the car makes sharp turns may have a CV boot problem. Replacing the boot and repacking the grease before failure occurs can fix the problem.