Surprisingly, the oil pump circulates oil in an internal combustion engine. The oil pump is a part of an engine lubrication system that pumps oil under pressure. It pumps oil from the sump through the galleries to the rotating bearing, the sliding pistons, and the engine’s camshaft. The system’s primary purpose is to pressurize lubricating oil to circulate within the engine’s moving parts. The pumped oil also maintained the temperature of the engine.
In this reading, we’ll explore what an oil pump is, its functions, diagram, types, and how it works.
Let’s get started!
What Is an Oil Pump?
The oil pump is a mechanical device that is used in an engine to circulate oil to moving parts like bearings, camshafts, and pistons to avoid wear and tear on the parts. It is one of the essential parts of an engine lubrication system that must not go wrong or be faulty; otherwise, a breakdown will occur.
Function Of An Oil Pump
The functions of an oil pump in an automobile include:
- Transferring oil to the essential parts of the engine under pressure.
- Ease movement of the engine lubricant around the engine.
- Offers direction to the movement of the oil through the galleries to various parts.
- It helps return the hot oil to the coolant oil in the reservoir.
- Keeps the oil circulation within the engine constant.
Diagram Of An Oil Pump
Types of Oil Pump
Below are the three types of oil pumps used in engines and how they work:
Rotor oil pump
A rotor type of oil pump is also called a gerotor pump. It contains an inner gear that turns inside the outer rotor. The inner rotor features one less lobe than the outer one, and it’s mounted slightly off-center of the outer rotor. This forces the outer rotor to spin at about 80% of the speed of the inner gear.
Twin Gear Pump
The twin-gear pump is also known as an external pump. It is mounted inside the oil pan on the bottom of the engine. it uses two intermeshing gears to pump oil. The first gear drives a shaft, and the first gear drives the second gear. The shaft that drives the first gear is usually connected to the crankshaft, camshaft, or distributor shaft.
Front-cover oil pump
The front-cover oil pump is also known as an internal or external pump. It’s often mounted in front of the engine cover. Its working is similar to that of the rotor pump, which uses an inner drive gear and outer rotor. In this case, the inner drive is mounted directly on the crankshaft.
Related: What Is An Engine Lubrication System? Its Functions And Parts
How An Oil Pump Works
From a strainer, oil passes into the oil pump and then flows through the heat exchanger, where it’s cooled. The cooled oil then flows through the galleries to the moving parts of the engine before returning to the sump. If an engine is designed with an injector, a small portion of oil is diverted to it.
The oil that is injected into the cylinder seals the space between the cylinder wall and the piston rings. This prevents the compressed air from escaping through the pistons, which increases the overall efficiency of the engine. An engine’s oil pressure generates up to 10 psi per 1000 revolutions per minute (rpm), which is about 55–65 psi.
The relief valve on the relative pump sets a pressure limit of 50 or 60 psi, but the crankshaft journal and bearing are subject to much higher pressures that can reach hundreds of psi. The relative speeds of the crankshaft journal in feet per second, not rpm, are what generate this high pressure. The bearing, the bearing width, oil viscosity, and temperature, balanced against the bearing clearance (the leakage rate), are considered.
Common Failures on Oil Pump
The failure of an oil pump could cause serious damage to a vehicle, especially if the driver did not know its failure symptoms. Well, drivers are notified when a problem occurs in the engine when the oil light indicator on the car’s dashboard is turned on, which alerts them that there is a problem. Below are the failure symptoms of an oil pump:
Low Oil Pressure
A faulty or worn oil pump won’t be able to properly pump oil through the system. This will result in low oil pressure and could cause damage to the engine. although there are several symptoms of low oil pressure, which were stated earlier in this pose.
Increased Engine Working Temperature
oil acts as a cooling agent in a vehicle’s engine as it reduces friction. The engine will be at normal temperature when the pump is in good condition and the flow of oil is constant. However, hot oil that cannot flow continues to lubricate the parts when the engine oil flow is slow or stopped.
Noise
A hydraulic lifter in a vehicle begins to make noise if it is not properly lubricated. When the oil pump is in good condition and the oil is properly circulated, these tend to be silent. The lifters are extremely expensive to replace, which is why it’s important that engines never lack oil.
