Oil Pump Buyer's Guide
The oil pump is a crucial component found in every internal combustion engine.
Most oil pumps are crankshaft-driven, which is why this type is often seen mounted over the nose of the crankshaft.
The three types of oil pumps are gear-type, rotor-type, and crescent pumps.
OE Oil pump replacements on CarParts.com retail with special price tags between $5 and $1,600 depending on the brand, condition, and quantity being sold.
A failing oil pump may result in engine overheating, noisy components, and a decrease in oil pressure.
Your car engine comprises of metal parts, most of which are in direct contact with each other as they move. In case you don’t know, metal-to-metal rubbing can generate heat through friction. This heat can weld the parts together and seize them from functioning. If this happens, your engine is gone for good.
To prevent metal-to-metal friction from damaging your engine, oil is circulated inside your engine—in between the moving parts. The oil we’re referring to is the motor oil, which is also known as engine oil. This oil sits inside the oil pan that’s attached underneath the engine block. Since the pan is located under the engine, oil is sucked up by the oil pump. The pump then delivers it upward, into the areas in your engine that need lubricating.
What is an oil pump?
The oil pump is a crucial component found in every internal combustion engine. It is an assembly made up of gears, springs, shafts, and gaskets that circulate oil from the oil pan to your engine’s bearings, pistons, camshaft, among others. Oil pumps are positive displacement pumps, which means that the amount of oil coming in and out of the assembly is the same.
Where is the oil pump located?
Most oil pumps are crankshaft-driven, which is why you’ll often see pumps that are mounted over the nose of the crankshaft. Aside from mechanically-driven pumps, electrical oil pumps are now also widely available, all thanks to technology. Generally speaking, oil pumps are located inside the lower part of your engine block, though some crankshaft-driven oil pumps are located outside the pan.
Also, dry-sump engines usually have two pumps: one for distributing oil and another for sucking out the oil pooling inside the sump. The extra oil pump is known as a scavenge pump and can often be seen in the oil pan or sump.
How does an oil pump work?
How an oil pump work may vary depending on the type of pump drive it uses. Regardless of the mechanism, oil pumps draw oil from the sump through a strainer. The oil flows past an oil pressure regulator that ensures the correct pressure before passing it to the oil filter. In some lubricating systems, an oil cooler is fitted to cool down hot engine oil before being reaching the oil spouts. The oil spouts are what sprays the motor oil to the bearings, pistons, and camshaft.
Types of oil pump mechanisms
As mentioned, there are different types of pump mechanisms that oil pumps use. These various types of pumps operate in three stages of the working cycle, which are filling, transfer, and delivery. Without further ado, here are the different types of oil pumps.
Gear-Type Oil Pump
The gear-type oil pump is regarded as the simplest oil pump type. It uses two meshing gears to suck in oil from the inlet and carries it around the housing wall and toward the outlet. Gear-type oil pumps produce a positive flow of oil. Once blocked, this oil flow can damage the pump due to an increase in pressure inside the housing. To solve this, a pressure release valve is fitted to rid excess pressure.
Rotor-Type Oil Pump
Classified as an internal oil pump, the rotor-type uses rotors to pump oil from the oil pan. A rotor-type oil pump comprises a rotor assembly made up of an outer ring (stator) and a physical rotor rotating inside it. The rotor, which is smaller than the area inside the stator, has an axis offset from the axis of the stator. A rotor usually has four or five external lobes, while the stator has five to six. The offset in the axis and the stator’s extra inner lobe create a clearance enough for the oil to accumulate as the rotor rotates.
Crescent Oil Pump
The crescent-type is another form of an internal oil pump that uses an inner rotor and an outer ring just like the rotor-type. What sets it apart, however, is the crescent-shaped seal that divides the oil as it travels inside the assembly. This crescent moon-shaped division also acts as a seal between the inlet and outlet ports.
How much is an oil pump?
OE oil pump replacement parts on CarParts.com retail with special price tags between $5 and $1,600, depending on the brand, condition, and quantity being sold. Products are sold either individually or as part of a kit. To easily find the best oil pump that fits your vehicle, indicate its year, make, and model on the filter tab. You may select from the series or brand listed under the “Shop By” menu to further narrow down your selection.
What happens when an oil pump fails?
Lubrication is essential in keeping your engine to optimal status, especially in long drives. Without proper lubrication, your engine would not survive long. The oil pump serves as the heart of your car’s lubricating system so it’s only logical that you keep it intact. If you’re curious as to what could happen when the oil pump begins to fail, here are some of the bad effects your car might face.
Oil pressure gradually decreases
The oil pump regulates the oil pressure based on temperature, engine speed, and the engine’s overall condition for the oil to properly reach the engine. A bad oil pump may cause oil flow pressure to decrease, resulting in inconsistent and inefficient oil delivery. When this happens, the oil warning light on the instrument cluster will illuminate to send a warning to the driver.
Temperature gauge continues to reach the H marking
Since there could be an insufficient amount of oil being delivered by a failing oil pump, moving parts will not be lubricated properly. Less lubrication means more friction and it’s no secret that friction generates heat. Oil flow shortage results in higher engine operating temperatures and may increase the risk of engine overheating. If the engine becomes too hot, the arrow of the temperature gauge will hit the “H” marking.
Noises in the valve-train
A failing oil pump may cause the components in your valve-train to operate differently due to reduced oil flow. As a result, components such as the pushrods and valve guide could become noisy as they move. They will also wear faster and may go on the fritz sooner than expected.
Unusual sounds from the hydraulic valve lifters
The hydraulic valve lifter, also known as the hydraulic tappet, is a device responsible for ensuring zero valve clearance in an internal combustion engine. It performs its job through the help of oil lubrication. Lack of oil supply due to a broken oil pump can affect the hydraulic valve lifter’s ability to keep zero clearance on the valves. This may result in unusual sounds coming from inside the valves upon closer inspection.
Choosing the Right Oil Pump for Your Vehicle
No matter how much oil you have stored in your oil reservoir and no matter how good the quality of that oil, it won’t do your vehicle engine any good if such oil cannot reach the engine’s various moving parts. In short, the oil will be useless if your car’s oil pump is malfunctioning.
Replacing a Damaged Oil Pump
Engine overheating is both costly and dangerous; it can lead to engine destruction and can render your vehicle immobile. There are many reasons your car engine can overheat, among which is damage to your vehicle oil pump. Good thing is, the pump is not that challenging to replace. Here, we’ll show you how to replace the pump when damaged so you can prevent overheating of your engine.
Difficulty Level: Moderate
- Replacement pump
- Replacement oil pan gasket
- Crescent wrench
- Oil drain pan
- Drive ratchet set
- Gasket scraper tool
- Safety goggles
- Latex gloves
Step 1: Park your vehicle on a flat surface and engage the parking brake. You can also place something behind the wheels to keep them from rolling while you are working.
Step 2: Place an oil drain pan under the engine. Using a crescent wrench, remove the oil drain plug and allow the oil to drain into the pan. Put the plug back in place.
Step 3: With a drive socket and ratchet, unbolt the oil pan from the engine block and take it off to gain access to the oil pump.
Step 4: Remove the oil pan gasket; you can do this using a gasket scraper tool. Clean the mounting surface of the engine block to remove any gasket material left over it.
Step 5: Using the drive ratchet, unbolt the pump and take it off. Then mount the new pump in place. Be sure to torque the bolts off correctly (the correct torque level ranges from 14 to 21 foot pounds).
Step 6: Mount a new gasket over the pan and reinstall it in place.
Step 7: Using a funnel, pour fresh oil into the engine. Then replace and tighten the oil reservoir cap.
After all these, you can run the engine and check the engine oil pressure to ensure that it’s correct.