Installing an Oil Air Separator!




OK the "real deal" oil air separator arrived from I made a neat upgrade last night to capture more oil and a drain valve. My wife's car has alot of oil in the blow by gases and these seriously mess with the car's fuel economy and emissions.

Read for how I installed this device into my wife's Hyundai trajet.

Step 1: The Make Shift Oil Air Separator.

I used a fuel filter to trap the oil before going into the air intake manifold. It worked somewhat OK but now I have to get rid of it.

Step 2: Securing the New Separator.

3 plastic cable ties did the job nicely to secure the separator.

Step 3: Adding Some Extra Sealant.

I used a thin layer of silicone adhesive to ensure vacuum integrity with the separator. I applied at the lid Jar joint, the sight level fittings and the hose fittings.

Step 4: Connection of the Vacuum Hoses.

I cut and secured each hose with the supplied hose clamps. I made sure to pay attention to which was for in and out. From the pcv valve the hose went to 'in' and the hose from the intake manifold went to 'out.'

Step 5: Completion!

Using some cable ties to neaten the works. Starting the engine, the car idled just fine. In time the separator will collect the oil in the blow by gases and keep the combustion chambers cleaner. Next job is to replace the oxygen sensor which has gone bad from the burnt oil crude.

I hope this instructable has been helpful!



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    4 Discussions


    2 years ago

    I have been brainstorming on the same concept, except I am looking at doing it to a diesel with a turbo.. A duramax which has two PVC valves. Is there a part number or product description for the separator. I wonder how much pressure / vacuum it can handle

    1 reply

    Reply 2 years ago

    Just search for oil air separator. I figure you will need a separator per pcv valve. Best of luck!


    2 years ago

    Try adding 50% gearbox oil to 50% 20-40 SAE normal engine oil . That thickens up the oil and stops it going past the rings somewhat . That will keep it going a bit longer. Won't do any harm unless you live in snow country then I would not do it.

    1 reply

    Reply 2 years ago

    Hmm. Good idea! I think maybe I will give it a try. Thanks for the idea!