An oil pan is a metal dish that covers the bottom of the engine block. It serves as a reservoir that keeps the engine oil, which circulates the engine. There is a pickup tube from an oil pump that enters the sump and draws up the oil.
In this reading, we’ll explore what an oil pan is, its function, diagram, parts, types, and how it works.
Let’s get started!
What Is an Oil Pan?
An oil pan is a shaped piece of stainless steel that covers an engine beneath and keeps lubricating oil when the engine is not running. The oil pan serves as a reservoir for oil that is pushed throughout the engine to lubricate, clean, and cool moving parts. It is attached to the engine’s bottom. Before passing through the engine, a pump draws the oil from the pan and filters it to get rid of grit and other impurities.
The oil pan can store four to six quarts of oil, depending on the engine, and is commonly composed of steel or aluminum. The oil dipstick is a device that is used to measure the amount of oil that is present in the reservoir. To drain the oil, remove the drain plug at the bottom.
Function Of An Oil Pan
The oil pan, also known as the oil sump, plays a crucial role in a vehicle’s engine. Here are its main functions:
- Storing the engine oil.
- The engine is covered completely, preventing external dirt from entering.
- Oil sumps also help in the cooling of lubricating hot oil as the vehicle moves. There is airflow under the sump, which helps to cool the hot oil before entering the engine for lubrication.
- There are cooling fins in the sump, which increase its surface area.
- Oil sumps help to keep big dirt and prevent them from entering the engine.
- The oil it contains is used for lubrication, cooling, and cleaning of the engine.
- With a dipstick, the oil sump allows the oil to be gauged.
- The oil pan/sump allows oil to drain out so new oil can be installed.
Diagram Of An Oil Pan
Related: What Is An Engine Lubrication System? Its Functions And Parts
Parts Of An Oil Pan
An oil pan (oil sump) is a relatively simple but essential component of an engine. It consists of several parts that contribute to its functionality. Here are the key parts of an oil pan:
Baffles
Due to the vibration of most engines, oil in the pan sloshes around as the vehicle accelerates and corners. This causes the oil to move away from the pickup pipe, preventing the oil from flowing properly through the engine. This is a bad situation that could starve the engine of oil. To avoid this, baffles are featured in the oil sump to prevent the oil from moving around.
Dipstick
As earlier mentioned, dipsticks are used in an internal combustion engine to gauge the amount of oil in the engine. By dipping the stick into the oil pan and removing it, the gauge can measure the oil level. An electronic sensor is used on modern engines to determine the level of oil on a dashboard indicator.
Windage Tray
The windage tray is a piece of metal sheet that prevents oil from splashing up onto the spinning crankshaft. it also has some form of crankshaft scraper, which removes excess oil clinging to the crankshaft counterweights.
Drain Plug
A drain plug is located on the body of the sump. It is a trading bolt that allows dirty oil to drain out of the oil sump. It features a washer, which should be replaced whenever the plug is removed. Oil is easily removed when warm.
Types of Oil Sump
There are two main types of oil sumps (oil pans) used in vehicles, depending on the design and requirements of the engine:
Wet Sump System
the wet sump system is the most common and standard oil sump in the automobile engine. It is called a wet sump because the sump carries oil, serving as an oil reservoir. It uses a single oil pump to transfer oil through the galleries.
Dry Sump System
the dry sump has an extra oil reservoir outside the engine rather than the oil pan. Oil is pumped out of the sump to a remote container. It works with at least two oil pumps; one sucks oil from the sump and sends it to the external tank. From the external tank, the second pump transfers the oil to lubricate the engine.
Related: What Is Oil Pump? Its Types and How it Works
How An Oil Pan Works
The lubricating oil is poured from the top of the engine, which flows from the camshaft to other moving components of the engine to the sump. The sump stores the oil when the engine stops working and the oil pump begins to suck the oil immediately after it starts running. The oil sump is designed to keep the oil in place so as to prevent the oil from sloshing around.
When the vehicle is moving, there is airflow under the sump that cools the hot oil, preparing them for lubrication. Though some sump features a cooling fin, which increases its surface area After some time, the oil will be dirty and need to be changed. At the bottom of the pan, there is a drain plug that will be open to allow the old oil to flow out. The plug will be screwed back after the oil is drained.
Oil Pan Problems
As engines age, they often have oil leaks, and seepage or leaks might originate from the oil pan. Leaks may occur from worn-out gaskets or seals placed where the pan meets the engine block. Drain plugs may leak if excessively tightened or if washers are not replaced during oil changes. Additionally, when a car travels off-road—intentionally or not—and strikes a rock or other hard object, the pans may sustain damage.