Cappuccino in autocross grid

Project Cappuccino: Installing an AOS

Interior of the J&L AOS
J&L’s AOS is very simple using some stainless steel mesh to slow the oil mist down and let it drop out of the air and into the catch can. Simple and effective.  The entire can is machined from 6061 aluminum and anodized in black (a clear finish is also an option). The bottom of the can is sealed with an o-ring and unscrews for easy draining. There is no sight tube so you’ll have to check it regularly.
Cappuccino engine bay
With an AOS in hand, we now need to mount it. The most obvious location is somewhere between the engine and radiator. There is a ton of free space and this is right in the middle of the hose routing path we need to take. If we mount it to the core support, both hoses will be pointed downhill better ensuring all of the oil drains into the AOS instead of getting to the intake. Additionally, the heat from the radiator will help evaporate out any condensation that builds up when the engine is cold. Perfect.
Homemade bracket to mount the AOS and intercooler
We made a simple bracket out of some 2” wide, ⅛” thick aluminum. This bracket replaces the upper mounting bracket for the intercooler and mounts the J&L AOS behind the radiator fan. It’s a simple solution and gives us plenty of space to remove the can to empty it. You can also see how the hoses point downhill towards the catch can. This will help ensure more oil is removed from the oil mist.
Capuccino engine bay with the J&L AOS installed showing house routing from the old crankcase vent to the can and the intake
This location makes the house routing really simple as well. J&L includes a pair of right angle ⅜” hose barb fittings. Conveniently, Suzuki chose this same size for the vent hose for the Cappuccino. We installed the fittings and bought some ⅜” hose from our local auto parts store, then connected it directly from the factory AOS, into the J&L AOS, then vented it to the intake fitting. Simple and effective.

The J&L AOS is really effective!  All of the oil we were seeing in our intercooler system is long gone.  We have to empty it every 1000km or so which isn’t bad at all.  The radiator fans blowing hot air onto the AOS keeps all the condensation out which helps extend our draining interval.  I really like how simple our homemade AOS system is.  Being completely bolt in means we can change or remove it at will too. 

Sources

J&L Oil Separator Company

More Cappuccino

Coast to Coast in 5 Days Part 1

Coast to Coast in 5 Days Part 2

Witchcraft & Wizardry

Blitz DTT and Wrapping Up The Interior

Better Braking With Project Mu 

Modern Tires, Ancient Car

A Terrifying Problem

Clutches, Oil Leaks, and Kei Car Oddities

A Wee Bit O’ Power

Testing the Kei Sport USA PNP ECU

DIY Lithium Battery Installation

Driveline Love

Upgrading the Suspension

Nuts & Bolts are Wheely Cool

Related Topics
1 comment

  1. Hi Dave,
    Fellow Cap owner here, enjoying your articles! Thank you.
    A clarification please, in your latest article about installing an AOS, you mention a gasket in the factory AOS which, if installed backwards, blows oil out of the exhaust.
    In your photo above this mention, is that gasket the correct way around (small square hole to the front), in your opinion?
    I ask because in the Cap service manual and Megazip parts diagrams, the gasket is drawn with the square hole to the rear (although the diagrams aren’t very clear!). When I checked my own car, the hole in the gasket was towards the rear, as per the diagrams.
    Best regards
    William McDougall

    Reply

Leave a Reply

Your email address will not be published. Required fields are marked *