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Radium Universal Air Oil Separator-Return (AOS-R) 20-0219

SKU 20-0219
by Radium
Original price $544.09 - Original price $544.09
Original price
$544.09 - $544.09
Current price $544.09

Like conventional catch cans, the Radium Engineering AOS (Air Oil Separator) kit is responsible for keeping blow-by oil and other pollutants out of the air intake and intercooler (if equipped) systems. The main difference is that an AOS system returns collected oil back into the oil pan so there is no servicing required.

A high powered modified engine tends to generate excessive blow-by oil and gasses. In these cases, an ordinary small catch can may quickly fill with oil and not be adequate.

Without a properly designed AOS, water condensation can develop and find its way in the oil pan contaminating engine oil. Engine coolant lines are routed through the Radium Engineering AOS in a specially designed heating chamber (shown above). This keeps the AOS warm and prevents water from condensing inside. Because water is more dense than oil, there is an integrated water trap found around the bottom perimeter that prevents condensation from descending into the oil pan. 

For AOS crankcase plumbing, the valve cover vent(s) are routed into the top inlet where the stainless steel condensing material separates the oil from the gasses. The filtered liquid oil is collected at the bottom of the AOS and drawn into the oil pan. Meanwhile, the clean crankcase air can either be vented to atmosphere (VTA) or recirculated to the turbo air inlet pipe.

- Effectively raises the octane and increases engine performance with cleaner inlet air
- Prevents oil buildup in the intake or intercooler system walls, throttle body, intake manifold, etc.
- Lowers hydrocarbon emissions

- Machined alumium Radium Engineering AOS
- Anodized universal mount that permits 360deg rotation
- Two 5/16" barbed fittings for coolant lines
- Stainless steel hardware 

- Top Port: 7/8"-14 threaded for 10AN ORB fittings
- Side Port: 7/8"-14 threaded for 10AN ORB fittings
- Bottom Port: 7/8"-14 threaded for 10AN ORB fittings
- Coolant Ports: 7/16"-20 threaded, includes two 7mm (or 5/16") barb fittings 

Would Suit :

Universal application

Other Information:


- In order for the AOS to function properly, a port must be supplied on the engine for the oil to return through.
- The AOS must be mounted high enough in the engine bay so that the port on the bottom is higher than the oil return port on the engine.
- For heating purposes, engine coolant must be routed to the AOS-R to prevent condensation.