An oil catch can is not one of those exciting and ‘sexy’ upgrades that you’ll put on your Christmas list for your 4×4 but it is definitely something you’ll look back on and regret not getting.
Because without a decent one, your vehicle could be severely compromised.
What is a catch can?
It’s exactly as the name says on the tin – it’s a can that catches excess oil from your engine. But how does a catch can work and why is it so beneficial, particularly for 4×4 drivers?
During regular operation of a diesel engine, it’s natural for bits of oil and water to escape into the crankcase. From there, it typically gets sucked back through the PCV, into the air intake, where it gets blown back into the engine.
The catch is what rests between the crankcase and the PCV and separates the fluid and mist from the crankcase and catches it, hence the name.
It’s important because of the exhaust gas recirculation systems that have been a part of modern diesel vehicles for some time now.
These systems recirculate a portion of the exhaust gas back into the engine to reduce carbon emissions, which wouldn’t be an issue if it wasn’t for what happens to that carbon if it’s left to its own devices.
Once the carbon mixes with the excess oil mist it creates a sticky black mess that can cake up your intake, leading to a major loss in power and efficiency.
Not only that, but oil can affect your intercooler, meaning you won’t be getting as much cool air into your engine.
The Flashlube Catch Can Pro can mitigate this potential headache and does so at a relatively minor cost.
The good and the bad
A good catch can will either contain a filter, steel wool, or some other kind of mesh to separate the particles effectively.
Without this filter, you’ll just have a can with an inlet and an outlet and it won’t be doing your vehicle any favours. Indeed, a really bad catch could cause engine damage or even explode under pressure!
You might assume that catch cans would come as standard on 4x4s but that’s unfortunately not necessarily the case.
Some people opt to circumvent the problem by running a pipe for the oil film directly to the inside of the chassis and others either electronically or manually block the EGR. Both of these tactics, however, are incredibly unsafe and even illegal in some countries.
What catch can do I need?
This will depend on how much oil runoff is produced by your engine and how often you want to be emptying it. These are not ‘fit and forget’ upgrades; they need to be inspected, drained and cleaned regularly.
Ultimately, an oil catch can doesn’t add any power to your rig and it doesn’t make it look any better, which is why it’s so often overlooked.
But if you want your intake to be completely clean and free of a goopy sticky black mess that stains everything it touches beyond recognition then it’s an investment you certainly won’t regret making.
Image: Volodymyr TVERDOKHLIB / Shutterstock.com
