I believe I somewhat understand what this does?? I'd love a good explanation.

I searched for it here and found nothing that was very helpful. I did see some suggestions that one was VERY IMPORTANT to add! I have seen them at various Mini parts vendors websites.

SO....what's the scoop? Is there one on my car?

Is this a factory item at all?

Is it actually so valuable to add?

IF so.... is there a DIY write up that would apply?

Remember, this is my first turbo car!! Odd little booger!

Thanks,

 

I've never seen a DIY write up about OCC's, maybe Wikipedia? However, here's some really basic info --- An OCC is an aftermarket addition to the PCV system, not a factory item. PCV systems re-circulate the crankcase vapors --- N14 thru the intake manifold --- N18 thru the turbo air inlet. Crankcase vapors contain oil, which will harm everything it touches, in the air / fuel supply. Installing an OCC separates the majority of this oil from the air, so relatively clean air gets re-circulated.

An OCC is a very worthwhile item to add to an N14, preferably to both PCV lines, however there are different ways to connect them. I'm using a Saiku Michi Dual OCC --- one for each line. There's only one line on the N18 so much easier and end result is the same --- minimum oil contamination in the air supply lines --- turbo, FMIC, throttle body, intake valves, spark plugs, etc. One downside is maintenance --- depending on engine condition the OCC might need to be drained quite often. Make sure the OCC you choose has an easy or convenient way to check quantity and remove the oil it catches. Check it maybe every time you fill the gas tank, until you learn it's consumption rate --- they're all different.

For the N18, vendor's installation instructions should be sufficient --- it's pretty simple. Sometimes, install instructions are available online, so you might be able to preview before you buy.

Have fun learning about the oddities ---

 

Thanks so much, good stuff.....I'm looking into one soon! I've seen a few that seem to fit the bill you just described.

Cheers

 

Just to reiterate what was stated above, the N14 has a bigger problem with carbon buildup than the N18 engine that is in your car. One of the major redesigns for the N18 was the PCV system, and I've read threads here that indicate that the N18 builds up carbon more slowly than the N14 does.

I guess that my point is, with your N18, an OCC won't hurt to install, but it would likely not be a major benefit.

On my old car (an 08), I had an OCC, but still had to have carbon cleaning done. The technology has improved since my car.

Have fun,
Mike