Crankcase Breathing Options

[Bulldog9]

As I round the final corner, I need to wrap up the crankcase breather and fuel tank vent system. The 912E has a fuel filler vent that runs from the tank to a canister up front, then runs a small vacuum line to the rear that plugs into what looks like a charcoal canister. This canister also has a larger inlet and outlet. I am assuming the outlet can go to the breather can, and also lines from breather can to the inside of the air filter on the carbs.

Looking at the left side of the fan housing on the type 4 motor, I see a nipple. I'm 99% sure that this is to go to the inlet side of the vac canister.

Based on some of my reading and files,, I've been planning a simple breather can.
http://www.hamincgroup.com/type4-test.php


I decided to draw out what I am planning, black lines are confirmed, the blue is what I am thinking. Anyone have recommendations or thoughts on this? I've seen breather cans that run from $80 - $300.

Thanks

[stugray]

Just one observation:
The Oil "chimney" that clamps onto the case is already the first stage of an "Air Oil separator" as it allows the circulating crankcase vent products to settle out in liquid and drain back to the case before exiting.

So you dont need a really elaborate external system. Just keep it simple.
I use the stock breather and the exit routes through a 3/4" hose to just a catch can (no drain back to engine) with a vent.
The catch can has a sight-glass so I can see if it ever starts to fill up, but after ~6 track days and ~500 street miles, it hasnt collected anything worth draining.
That's with a fresh motor.
And I do not have head vents.

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1442786201.1.jpg)