How Oil Pump Working And Their Types?


You could see a sophisticated network of pieces working together effortlessly when you consider how an automobile engine operates. The oil pump is one important part that guarantees an engine runs smoothly. In-depth discussions about oil pumps, their various types, common failure indicators, and much more will be covered in this article. This manual will give you useful insights into the engine’s core, whether you’re an enthusiast for cars or just interested. An efficient oil pump ensures proper lubrication, reducing friction and heat in engine components. This improves overall engine performance, enhancing power, fuel efficiency, and longevity.

Define oil pump

A component of an internal combustion engine, the oil pump pushes engine oil under pressure to the engine’s rotating bearings, sliding pistons, and camshaft. This helps to cool the engine and lubricate the bearings while also enabling the use of fluid bearings with larger capacities.

Pressurized oil is increasingly employed as a hydraulic fluid to power small actuators in addition to its basic application for lubricating. For actuating camshafts and valves, hydraulic tappets were one of the first prominent applications of this method. Recent applications may include variations for variable valve timing systems or the tensioner for a timing belt.


The type of pump used varies. Gear pumps, trochoid pumps, vane pumps, and vane pumps are all commonly used. Plunger pumps have been used in the past, but these are now only used rarely for small engines.

To avoid the need for priming, the pump is always mounted low, either submerged or around the level of the oil in the sump. A short pick-up pipe with a simple wire-mesh strainer reaches the bottom of the sump.

Oil pressure

The oil pressure generated in most engines should be about 10 psi per 1000 revolutions per minute (rpm), peaking around 55–65 psi.

Local pressure (at the crankshaft journal and bearing) is far higher than the 50, 60, et cetera. set by the pump’s relief valve and will reach hundreds of psi. This higher pressure is developed by the relative speeds in feet per second (not RPM or journal size directly) of the crankshaft journal itself against the bearing, the bearing width (to the closest pressure leak), oil viscosity, and temperature balanced against the bearing clearance (the leakage rate).

All pump pressure does is “fill in the hole” and refresh the oil in the annular space faster than the leak expels it. This is why low-speed engines have relatively large journals with modest pump sizes and pressures. Low pressure indicates that leakage from the bearings is higher than the pump’s delivery rate.

Understanding Engine Oil Pump

The Circulatory System of Your Engine:

Consider the oil pump as the vehicle’s circulatory system and the engine as its heart. In order to reduce friction between moving parts and avoid excessive wear and tear, engine lubrication—maintained by the oil pump—is vital. Similar to how blood delivers oxygen and nutrition through the body, engine oil lubricates essential engine parts, guaranteeing their optimum performance.

Working Principle

The Heartbeat of Lubrication:

The oil pump functions primarily according to a straightforward but efficient principle. It pulls oil from the oil pan, pressurizes it, and then distributes it to other engine components via a network of tubes. Between moving parts, this pressurized oil creates a shield that prevents metal-to-metal contact and distributes heat.

Oil Pump Types

Oil pumps come in several types, each designed to meet specific engine requirements:

Gear Pumps

One of the most prevalent different kinds of pumps in engines is the gear pump. To lubricate the engine parts, they use meshing gears to generate a vacuum that sucks oil in and then forces it out under pressure.

Vane Pumps

In housing that revolves, vanes used in vane pumps create chambers that catch and release oil as they rotate. These pumps are frequently utilized in high-performance engines and provide smoother oil distribution.

Gerotor Pumps

Gerotor pumps, which have an inner rotor with lobes that move within an outer rotor, combine components of gear and vane pumps. This innovative layout improves oil flow and effectiveness.

Oil Pumps in High-Performance Engines

Powering Performance:

The demands placed on the oil pump in high-performance engines are even higher. These engines frequently run at higher temperatures and RPMs, so a strong oiling system is necessary to ensure appropriate lubrication. To address the aforementioned requirements, upgraded oil pumps with sophisticated designs are frequently used.

Common Failure Signs of an Oil Pump

Recognizing the Red Flags

While oil pumps are designed for durability, they can still develop issues over time. Some common symptoms of a failing oil pump include:

  • Low Oil Pressure Warning:

An oil pump issue may be indicated by a low oil pressure warning light or gauge on the dashboard.

  • Loud Engine Noise:

Excessive engine noise, which is frequently referred to as ticking or knocking, may be a sign of inadequate lubrication.

  • Overheating:

Since oil also aids in removing heat from the engine, inadequate oil circulation can cause overheating.

  • Increased Friction: 

Insufficient lubrication may cause a dragging or grinding sensation when driving.

  • Check Engine Light:

Inconsistent oil pressure caused by a broken oil pump might cause the check engine light to come on.


The oil pump assumes a central role in the complicated symphony of an internal combustion engine, ensuring that all the moving elements function harmoniously. Its function in ensuring proper lubrication is essential for the engine’s durability and functionality. Understanding the many kinds of oil pumps and spotting failure symptoms equips car owners to take preventative action, safeguarding the engines of their vehicles for years to come.


How often should I replace my oil pump?

A: Although oil pump replacement schedules vary, it is advised to stick to the manufacturer’s recommendations.

Can a blocked oil filter impair the efficiency of an oil pump?

A blocked oil filter can restrict oil flow and affect how well the oil pump functions; thus, the answer is yes.

Are high-pressure oil pumps necessary for everyday driving?

A: Unlike everyday commuter use, high-pressure oil pumps are mainly utilized in high-performance and racing applications.

What’s the average cost to replace an oil pump?

A few hundred to more than a thousand dollars might be spent, depending on the brand and model of the car.

How can I prevent oil pump failure?

You may avoid oil pump failure by doing regular oil changes, using high-quality oil, and adhering to recommended maintenance procedures.