What is Oil Pump in a Vehicle and How Does it Work?

The working system of every possible machine involves elaborate and complex mechanisms that cumulatively enhance its productivity. Similarly, an oil pump is one of the requisites of every machinery, since it plays an essential task of oil circulation. 

They allow lubrication of the machines, thus allowing them to function seamlessly without undergoing corrosion.

Simply put, an oil pump is the heart of an engine. It operates under pressure and circulates oil to different parts of an engine, thus allowing it to function smoothly. The rotating bearing, camshaft, and pistons of your engine rely on the oil, just like a source of energy, for functioning.

Here are some essential functions of an oil pump:

• It circulates oil and ensures that an engine functions smoothly with sufficient lubrication.

• It ensures that engines do not undergo wear and tear due to constant subjection to friction.

• It circulates the oil in a specific direction through engine galleries.

• It stores the hot oil in the reservoir

Mentioned below, are the three most popular types of oil pumps available in the market.

1. Rotor Oil Pump

Rotor pumps are usually positioned inside the crankcase so that they can conveniently draw the oil and circulate it to the parts of an engine. They comprise special distinctive rotating inner and outer gears. However, to ensure maximum efficiency, the inner gear comprises one less lobe that is positioned slightly off the centre.

However, this type of oil pump requires meticulous calculation and accurate measurements to ensure seamless functionality.

2. Twin Gear Oil Pump

A twin-gear pump lies within an oil pan at the bottom of an engine. This type of oil comprises two meshing gears that operate together to effectively pump oil to the engine parts. Interestingly, a shaft connected to a camshaft, connecting gear, or crankshaft, moves the first gear. Similarly, the first gear effectively moves the second gear.

3. Front cover oil pump

Front cover oil pumps, also known as internal or external pumps, are almost similar to rotor pumps. They consist of an outer rotor and an inner gear that is directly attached to a crankshaft. Consequently, it eliminates the need for a separate pump driveshaft. 

With this unique structure, a pump rotates at the same speed as that of an engine thereby producing high oil pressure.

Here is a vivid explanation of the working of oil pumps. The pumps are connected to an engine. They start pumping oil when an engine starts running.

• Step 1: Initially, the oil passes through a strainer that separates debris or large particles.
• Step 2: In the next step, the oil enters the pump which is primarily responsible for generating pressure that circulates the oil throughout an engine.
• Step 3: At this stage, the oil will flow through a 'heat exchanger' where it undergoes a mandatory cooling process.
• Step 4: In this step, the oil passes through the 'galleries' that direct it to flow through the crankshaft, piston, and camshaft of an engine.
• Step 5: At this stage, the oil comes back to settle in a sump. A sump is a storage tank or reservoir that stores this oil for later use.

Certain engines come with an injector that receives a portion of the oil. This locks the space between the piston ring and cylinder walls, thus preventing air from escaping. Consequently, this enhances the efficiency of an engine.

Failure of an oil pump often signifies that it is incapable of adequately circulating the oil to the engine parts. This leads to a severe degradation of the engine performance. Here are a few symptoms that indicate your engine's oil pumps might not be functioning properly.

Flashing of Oil Light Indicator

A warning sign on an oil light indicator signifies the malfunctioning of a pump. An oil pump regulates the pressure of oil and ensures its smooth circulation in your engine parts. However, a glitch in your oil pumps deteriorates the pressure of the oil.

Elevated Engine Temperature

The circulation of sufficient oil by a pump is necessary for a hassle-free functioning of an engine. With insufficient oil flow, an engine undergoes constant friction and wear and tear, which elevates its internal and external temperature. This excess heat may damage your engine and most of its vital components.

Noisy Valve Train

A valve train comprises essential engine components like hydraulic lifters, valve guides, push rods, and seals. These integral parts require oil for lubrication that allows them to function effectively. However, inadequate oil provides insufficient lubrication, thus increasing friction between engine parts. As a result, this valve train makes a noise suggesting a malfunctioning of its oil pump.

Noisy Oil Pump

A whirring sound from the engine even while it is not running, suggests severe malfunctioning of an oil pump. While this is a rare event, noise is an ultimate warning signal prompting you to take immediate action. In such cases, you must replace the pumps with new ones.

Noisy Hydraulic Lifters

A noisy hydraulic lifter is yet another warning symbol hinting towards an oil pump failure. These hydraulic lifters are a primary driving force behind the functioning of a valve train. However, they do not receive adequate lubrication when a pump fails to deliver sufficient oil. Consequently, this causes malfunctioning hydraulic lifters to produce noise.

To conclude, an oil pump plays a vital role in the overall functioning of an engine. Moreover, with rapid development in technology, the usage and efficiency of oil pumps will continue to upgrade and reach newer heights. However, despite the involvement of new and cutting-edge technology, one must be mindful of the efficiency of pumps, and take utmost care as much as possible.