How your car engine works and helpful maintenance tips

Bob has been driving his Toyota Premio for the last four years. While the car has been dependable over those years, lately his fuel consumption is worryingly high. A round trip to Namugongo now costs him Shs35,000 up from the Shs25,000 he used to spend. A mechanic suggested possible engine issues he needed to look into that could be reason for this fuel spike. He cited attention to be given to possibly worn out spark plugs, a clogged air filter or relatably a dead oxygen sensor.
Engine problems can lead to various issues because the car will not be performing as it was intended to. The engine is the fuel combustion powerhouse that drives a vehicle. It is a set of intricately woven parts like valves, pistons, timing chain, crank shaft etcetera that work in perfect harmony to burn fuel and produce movement.
Since major engine repairs like engine rebuilding or total overhauls are quite expensive it is imperative that you maintain the working order of your car’s engine.

How a car engine works
To get an understanding of why it is important to properly maintain your engine, a basic understanding of how this vital component works is good to have.
According to Richard Katumba, a mechanic, the engine is made up of a cylinder which houses a set of pistons. Depending on the power of the engine, these pistons could number anywhere from four to six to eight cylinders. The arrangements of these pistons could be inline (vertical) in a V shape or flat (Horizontal).

The pistons are encased within the cylinder and are attached to the crankshaft by connecting rods. Mzee Katumba adds that a valve lets fuel and air into the cylinder using an injector. As the valve closes the piston moves up compressing the air and fuel mixture, which is ignited by spark plugs, located at the top of the cylinder. This creates an explosion, which produces hot gas that forces the piston down and transfers this kinetic energy to the crankshaft. This turns all the moving parts of the engine. Because the engine has a number of parts that move at very high speeds, there are two main systems that minimize wear and prevent excessive heat from being generated.

The engine cooling system
Mzee Katumba opines that a good engine should be able to operate within its recommended temperature. It should be able to maintain this even when the vehicle runs for extended periods such as on a long up-country trip. At the center of the cooling system is the water pump. This is a device that pushes coolant through the engine block and maintains the recommended temperature for components in the engine. The pump is driven by a serpentine belt/ fan belt, which is made of a durable rubber compound. Coolant is circled within a water jacket that is located around the cylinders where the actual combustion takes place.

Water that has flowed around the engine is channeled by hosepipes to the radiator where it is cooled before being sent back to the water pump for another set of pumping. A leak leads to coolant loss and eventual overheating.
He also stresses the need to replace a worn water pump to prevent the engine from over heating and possibly burning the gasket or cracking the cylinder head. This can lead to very expensive repairs so regular checks are a must do. When prodded on how you can tell if your water pump is dead, he said that the water pump may leak or make a whining sound as the engine runs. These are signs that you should not ignore.

Engine lubrication
Aside from cooling, your car engine needs optimum lubrication to reduce friction. Friction is the number one culprit that leads to engine wear. Robert Kasule a service technician at a petrol station in Ntinda says that oil enables the moving parts of the engine reduce the harsh effect of metal rubbing against metal. Remember that engine parts move at very high speeds so the effect of friction can be extremely pronounced. It is for this reason that another function of the engine oil is keeping the engine cool. Lubrication reduces the effect of friction which drastically leads to the generation of less heat.
Oil also acts as a detergent that keeps the engine clean. Engine oil has cleaning agents as part of its composition, which help keep the moving parts of the engine clean. Overtime wear particles and sludge need to be washed out by maintaining a regular oil change regime. Sludge is formed after oil has broken down due to repeated use.

Ways to maintain your engine’s health
Use recommended engine oil
Robert Kasule, a mechanic says one needs to choose engine oil from a reputable service station and ensure that is has a factory seal. As the adage goes “Cheap can be expensive.” If you drive a newer European car ensure that the oil is approved by your vehicle’s manufacturer. Many newer European cars have engines that are complex and have a list of approved oils for lubrication. Engine oil costs about Shs80,000 for 4 litres while synthetic oils costs about Shs150,000 for the same quantity.

Ensure cooling system works
Parts of the cooling systems that you need to check regularly include the radiator and water pump. Ensure that your radiator is not leaking and if you come across any leaks have a mechanic address that. Mzee Katumba says that you may need to buy a new radiator top if your existing one is perforated. These cost about Shs150,000 and prices may vary depending on the your vehicle.

Genuine coolant
Also use a good coolant from a reputable service station to keep your engine temperature acceptable. Beware of fake coolants on the market that form hardened particles when used in car engines. Coolant also prevents rust from building up in the internal parts of your engine. Do not be tempted to run your engine cooled by only water as a money saving gimmick.

Replace your air filter regularly
Air is needed by your engine for the combustion process to be completed. As you drive, your car comes into contact with dust, insects, leaves, sand. These particles need to be prevented from entering your engine. According to Kasule, an engine air filter needs to be replaced after about five service intervals or sooner depending on how clogged it has become. Air cleaners cost anywhere from Sh40,000 or more depending on your type of vehicle. Although they normally don’t cost much, air cleaners play an immense role for your engines health. If you drive on long stretches of dusty road every day then you might need to change your air filter more often.