Isuzu 4JJ3 Air / Oil separator

The 4JJx platform is renowned for a heavy crank case pressure build up, especially under heavy boost/fuel modifications!

We have a solution where you remove the restrictive oil vapour valve,
fit the new AOS stack and route the intake plumbing to the new fitting!

Fitting time is typically about 5 minutes with basic tools (But allow 30 minutes for first time installs)

This is a highly suitable addition for CATCH CAN applications and also for stock plumbing if you are trying to relief the crank case pressure (although we suggest no catch can is used).

The reduction in oil coagulation in the air intake (of our own vehicle) over 600kms we have measured is over 80% and far exceeds catch cans we have tested (without the stress on the engine of excess back pressure!)

The measured crank case pressure that has been measured to be between 2 psi on low load and up to 15 psi on high load in our tests.

This means, more power, less chance of blowing seals and a cleaner intake / EGR system.

And the best thing, it is completely legal.

Notes on fitting:
The supplied O-ring seal is usually a perfect fit, in the case you cannot get a perfect seal for the original pop-up vent tube, a second o-ring is supplied. In the extremely unlikely event the installer cannot get a long term seal, the original crank case vent tube can be completely blocked when the Boostec AOS is installed (Such as with a barb cap or filling it with RTV if you are in a pinch)

When fitting, you will need to trim the original gasket to remove the solid button center.  Be mindful that a spring is also present in the OEM vent, ensure it is removed entirely from the engine (Do not loose it in the crank case vent!)

Always EVENLY screw down the AOS onto the gasket in X fashion.

No NM rate is supplied as the screws used in OEM are into plastic. Only use enough torque to get a seal.