How To: Cheap Oil Catch Can

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How To: Cheap Oil Catch Can


Post by Laecaon » Sun Apr 12, 2015 4:33 pm

About to try some stuff on the BMW, so I decided it was a good idea to install an oil catch can, especially since I have deleted the stock PCV system. It also catches the oil before it goes back into your intake, which in turn will help keep your intake and valves a bit cleaner.

There are a ton of catch cans on the market, ranging from cheap to quite spendy. There is no reason for this, as its a really simple device. So after doing some research, I decided to use a air compressor water/oil separator.

So its a pretty simple mod. I will keep it brief with how I hooked it up to the car as its more or less specific to the BMW.

Your list of supplies will vary depending on application.
First off, the catch can itself: ... 5yc1vZc9n8
Then you will need any fittings that are required for your application. FYI, the catch can/filter takes 3/8 NPT or MIP.
And finally any hoses that go with the fittings you got. I used 3/8" heater hose.

Here is the filter:

Step one, remove the stickers:

Step two, Remove the twist valve thing:

Step three, epoxy or JB weld the valve shut. The valve works great with pressure from an air compressor, but not so much with vacuum from the manifold.

Step four, while the epoxy is drying, make your bracket. I happened to have an old metal shelf so I just needed to put a hole in it to hang the filter.

And Paint:

Step five, install your fittings, I ended up using a different fitting than shown.

Step six, install

Finally, the rest of the install is just routing hoses, and connecting to the engine. One side connects to the crankcase vent whether that is the valve cover or crank case itself, The BMW only had a Valve Cover vent, I know the L series has 2. The other side of the filter connects to the intake manifold.

I will update as I drive the car. Currently, my thinking is the filter may need a bit of modification to further help the separation of oil and air.

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Re: How To: Cheap Oil Catch Can


Post by DRIVEN » Mon Apr 13, 2015 5:06 am

Looks good. And should work well too. If I might make a suggestion, you could use an EFI style hose clamp and it would appear almost factory.
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Re: How To: Cheap Oil Catch Can


Post by izzo » Tue Apr 14, 2015 8:16 pm

Ha! Dude, that is awesome. Small yet works and can be tucked just about anywhere. Giving rep yo!
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