What are the functions of engine crankcase?

In a reciprocating internal combustion engine, the crankcase functions as the housing for the crankshaft. The crankcase is placed into the engine block in most modern engines. It also serves as a casing for the engine parts, protecting them from dust, water, and mud splashing.

The crankcase holds the lubricating oil needed to keep the engine parts lubricated. The crankcase is large enough to hold the rotating crankshaft and connecting rod. The crankcase also houses many components such as a carburetor, fuel pump, generator, water pump, air cleaner, starting motor, fan, oil filter, oil body of cooler, and so on.

car engine crankcase

The crankcase not only supports the engine parts and mountings, but also bears the loads imposed by piston thrust, gas pressure, primary and secondary forces, couplings, and other factors. To withstand these loads and pressures, the crankcase must be strong. Grey cast iron is used when the cylinder block and crankcase are cast together as a single unit because of its rigidity, low cost, and high wear resistance.

Read more: Components of internal combustion engine

Crankcase compression is common in two-stroke engines, which means the fuel/air mixture passes through the crankcase before entering the cylinder. The crankcase does not have an oil sump in this engine design.

The majority of the engine’s oil is retained within the crankcase in four-stroke engines, which typically have an oil sump at the bottom of the crankcase. In a four-stroke engine, the fuel/air combination does not flow into the crankcase; however, a tiny amount of exhaust gasses from the combustion chamber frequently enters as “blow-by.”

There is no crankcase in an open-crank engine. This design was employed in early engines and is still used in some large diesel engines, such as those seen on ships today.


What is a crankcase in an automobile engine?

The crankcase serves as the “body” of the engine, holding all of the other components together. It is the engine’s largest component, but it must be both sturdy and light. The brothers made the crankcase out of aluminum to keep the weight down. The crankcase was made in a Dayton foundry.

Read more: Understanding Engine Lubrication System

What does a crankcase do?

The crankcase is a drilled metal frame that houses several elements, including the crankshaft, of an internal combustion engine. Its primary purpose is to protect the crankshaft and connecting rods from debris.

Is crankcase oil the same as the engine oil?

engine oil (crankcase oil, motor oil) is a lubricant that is carried in the crankcase, sump, or oil pan of a reciprocating internal combustion engine to lubricate all key engine elements; it is also used in reciprocating compressors and crankcase steam engines.

Where is my car crankcase located?

The crankcase is normally found on the cylinder block’s bottom. The space around the crankshaft and crankshaft bearings is known as the crankcase. The moving crankshaft and crankshaft counterweights are enclosed in this compartment, and returned oil is directed into the oil pan.

What is crankcase ignition?

The same “hot spot” that created the oil mist could cause the ignition. If a substantial amount of oil mist has formed before ignition, the burning can generate a massive increase in pressure in the crankcase (explosion), forcing the relief valves to open momentarily.

What is the purpose of crankcase ventilation?

An internal combustion engine’s crankcase ventilation system eliminates undesired gases from the engine’s crankcase. A tube, a one-way valve, and a vacuum source are commonly included in the system (such as the intake manifold).

Does engine oil go into the crankcase?

Because it controls the fuel/air combination, the crankcase does not receive any oil, unlike other types of engines. Two-stroke oil is combined with the engine’s gasoline and burned in the combustion chamber instead.

How much does it cost to replace a crankcase oil filter?

The cost of replacing your crankcase breather filter is typically between $200 – $300. It’s worth noting that the parts alone would set you back around $100 – $105, with labor costs ranging between $90 – $120.

Is crankcase cleaning necessary?

A crankcase flush is generally unnecessary. The vast majority of engines on the road are spotless on the inside and will remain so as long as they are properly maintained. You’ll be alright if you change your oil on a regular basis and use a good filter.

What is the difference between engine block and crankcase?

The engine block has integrated cylinder heads, but the crankcase is independent. The oil sump is located in the bottom portion of the crankcase.

Read more: Understanding fuel injection system in automobile engines

In Summary

A crankcase is a part of an automobile engine that collects the engine oil and makes it recirculate back to the engine moving components. The engine parts also serve as cover that prevents dirt from entering the internal part of the engine.

I hope you learn a lot from the FAQs explained on the crankcase, if so, kindly share with others. Thanks for reading, see you around!

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