Air Oil Separator vs. Catch Can: What you should know

Have you ever wondered how an air oil separator differs from an oil catch can? This post will describe the main differences between the two and help you decide which one to choose.

Baffles are used in both oil catch cans and air oil separators to trap oil circulating through your PCV system and prevent it from being recycled to your engine. The design and quantity of baffles used in an oil catch container and an air oil separator are the key distinctions.

Air oil separators usually have more baffles and are capable of returning captured engine oil to the engine. While using an oil catch can, you will need to drain the captured engine oil regularly.

An oil catch can or an air oil separator: which is better? Which is the more expensive option? Continue reading to learn more.

Related Post: How To Check Your Radiator Coolant Overflow Tank?

What is an Oil Catch Can, and how does it work?

A catch can sometimes call an oil catch can, is a container that connects to your engine's existing PCV system. An oil catch can is a device that collects oil from your PCV system to prevent it from entering your air intake and causing carbon buildup.

Most oil catch cans accomplish this by sending air from your crankcase through the catch can, which is equipped with baffles to help capture the oil. Most oil catch cans will include a dipstick that you can check to see whether the container is almost full of oil. You might then empty the oil catch container once it begins to fill up with oil.

What is an Air Oil Separator, and how does it work?

An air-oil separator is essentially a more advanced version of an oil catch can, with more baffles to completely separate the oil from the air/oil mixture and prevent it from entering the air intake. Air oil separators are also meant to automatically return oil to your engine rather than having to manually dump it as an oil catch can.

If you plan on bringing your vehicle to a race track or drag strip, an air oil separator may be preferable over an oil collect can due to the possibility of old oil entering into your air intake with an oil catch can.

If you failed to empty your oil catch can or it was partially full as you went into a hard turn with an oil catch can, the oil could pour into the air intake, which would be disastrous.

Because air oil separators are continually discharging the oil they catch back into the engine, you won't have to worry about this happening with them. Air oil separators will also require less maintenance than oil catch cans for this reason.

Why Use an Air Oil Separator Instead of a Catch Can?

A PCV system will be integrated into the engine of the majority of cars made today. Positive crankcase ventilation is referred to as a PCV system. When your engine is running, the piston rings allow some air and oil from the cylinder to pass through the piston and into the engine's crankcase.

This is known as a blow-by. If you didn't expel the air and oil mist from the crankcase, the gaskets on your valve covers would be blown out, potentially damaging your engine.

Your engine's PCV system is designed to take this blow-by air and oil mixture and send it back into the air intake. When this happens, part of the oil in the air/oil mixture will be deposited in your engine's air intake.

This isn't an issue with engines that use port injection, which means the fuel is pumped directly into the air intake port because the fuel can clear the carbon buildup and prevent it from occurring in the first place.

However, not all engines are created equal; some engines do not feed fuel into the air intake port, which can lead to carbon buildup concerns. Installing an oil catch can assist reduce carbon buildup in your air intake and air intake valves on these types of engines.