The engine’s main function is to allow a small amount of gasoline and air, contained in a small enclosed space, to ignite and explode, generating energy that sets various mechanisms into motion to turn the wheels of the car. A constant cycle of these little explosions inside the engine runs your automobile. Literally hundreds of things can keep an engine from running properly, the main ones being a bad fuel/air mix, lack of compression, or lack of spark. The engine is the heart of an automobile’s life, so let our trained mechanics at Mike's Service Auto Body in Narragansett, Rhode Island help you keep your car’s engine and all its parts working perfectly.

Gasoline and air, with the right spark, combust within the engine, making the car run.

1The ratio of gasoline to air must be just right. If the fuel system supplies too much or too little fuel, combustion won’t occur properly. If there is an impurity in the fuel, it might not burn. Assuming you have the right mix, where do the gasoline and air go? Into carefully sealed cylinders, where all those little explosions happen.

Automobile cylinders contain pistons that rotate constantly, setting everything in motion.

An automobile’s piston, a cylindrical piece of metal housed in an enclosed cylinder, moves in a cyclical pattern. When it starts to move down from the top of the cylinder, an intake valve opens, letting in a small amount of air and gasoline. Then the piston moves back up to compress this fuel/air mixture. When the piston reaches the top of its stroke, a spark plug emits a spark to ignite the compressed gasoline. The resulting explosion drives the piston down again, repeating the whole process over and over. At the bottom of the stroke, an exhaust valve opens and the exhaust leaves the cylinder to go out the tail pipe. On one side of the piston is what is called the combustion chamber where the fuel and air are ignited. On the other side is the crankcase which is full of oil needed to lubricate the engine during all those movements. Pistons have rings which serve to keep the oil out of the combustion chamber, as well as the fuel and air out of the oil. All of that has to be in perfect balance for the thing to work right. The compression of the gas is important. If there’s a hole in a cylinder, usually at the cylinder head where there is a little gasket, it can cause leaks and prevent compression or combustion.

The valve train is a combination of parts, including the camshaft, that let air and fuel in the engine at the proper time.

All those little valves and rotors and bits and pieces of things have to work just right to be sure your automobile’s gas/air ratio is correct and admitted into the cylinder at the right moment.

A timing belt or chain tells a camshaft when to open and close the valves.

Timing is everything in an engine. If the timing belt breaks, slips, or loosens, it can throw off the timing of the camshaft’s opening the values in the cylinder, thus interfering with the combustion, or preventing it entirely. Because timing belts take a lot of wear, it’s a good idea to change the timing chain or belt every 60,000 miles or within six years.

Spark plugs ignite the fuel.

The spark plug supplies the spark that ignites the air/fuel mixture. Timing is important, because the spark must happen at just the right moment or the fuel will not ignite at the right time, creating problems. If the spark plugs go bad, or if the wire going to the spark plug is damaged or interfered with, there will be no spark.

Valves have to open at just the right time to let in air and gas, and let out exhaust.

The intake and exhaust valves open and close constantly, at just the right times, but both valves must be closed during compression and combustion, sealing the combustion chamber or the compression won’t work. If your car is out of gas, the valve will open but the engine gets no fuel, and won’t start. If the air intake gets clogged, there may be fuel but not enough air, and the car won’t start. Keeping these valves operative is essential.

Piston rings seal things up.

1Piston rings provide a seal between the piston and the cylinder. They prevent the fuel/air mixture and exhaust from leaking during compression and combustion. They also keep oil from leaking into the combustion area. Most cars that "burn oil" are burning it because the engine is old and the rings no longer seal properly which allows both 1) the fuel and air to enter into the oil and dilute it, reducing the oil’s ability to lubricate the engine, and 2) allowing oil from the crankcase to enter the combustion chamber, resulting in oil being burned needlessly and exiting the tailpipe as grayish/white smoke

The connecting rod connects the piston to the crankshaft, which finally gets things rotating.

The connecting rod can rotate at both ends so that its angle can change as the piston moves and the crankshaft rotates. As the piston moves up and down in the cylinder it rotates the crankshaft and converts the straight line motion of the pistons into rotary motion. The crankshaft rides on bearings supporting the crankshaft. If the bearings wear down, it means removing the crankshaft and repairing it or replacing the entire crankshaft. To prevent this problem, lubricate the system regularly; change your oil at thee months or 3000 miles, and watch your oil level at all times in case of a leak.

Engines do remarkable work and if properly maintained can last a very long time. Whether you need repair, maintenance, or advice about whether or not it is time to put a new engine in your automobile, the mechanics at Mike's Service Auto Body in Rhode Island are ready to help you take care of your automobile’s engine.





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