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Breathers (again...)

Greetings fellow enthusiasts:

I've just completed building a VW Trike. I'm using a freshly rebuilt

1776 with dual Kadrons. I tried to do everything right, but with limited knowledge on some systems (like breather), so I have a mickey mouse EMPI breather box - presently connected to both valve covers and the vent connection on the oil filler. I'm using heavy wall tygon tubing for connections, and the tubing is filling with oil foam. I know I need to get the engine hotter and take more highway trips. I have a couple of questions:

Any opinions on the CB Performance high performance breather box that attaches to the oil filler?

Could I modify the EMPI to perform the same function by sealing the top and connecting it to the air cleaners? Right now, there is no connection to the air cleaners. That in combination with a new engine is causing some blowby in around the pulley, which I'm hoping connecting properly will eliminate. I am going to put hose connections on both air cleaner covers to connect to the breather box.

Do I really need a breather box at all? Could I just tee the oil filler vent into both air cleaners?

If I seal the EMPI up, what's the opinion on simply putting filters on the valve covers rather than running hoses up to the box?

What about a road vent tube - is it necessary to have one on the box? Right now when I open it up there's a large puddle of water at the bottom, which is being held by the sponge.

I know this is an old topic, and I've read lots on it, but it's difficult to get a concensus - lots of different opinions - so I thought I'd try another direct post.

Thanks,

Bob

Reply to
Bob
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The 1st thing you need to do is to cut the foam so that there is about a

Reply to
Nor-Cal VW's

I have that same style of breather. Mine is made by Scat. My breather is connected to the oil filler on the bottom and to both air cleaners on the sides. I removed the foam element (which doesn't allow any breathing to occur) and replaced it with a piece of metal screen (the screen door type) about an inch wide that I rolled up several times into layers filling up the inside of the box. I placed it inside the breather box. I also put oil breather element gauze on the ends that lead to the air cleaners (bought the gauze a the LAPS). I did not seal the box. The concept here is that as the carbs draw in air from the crankcase, most of the oil from the oil vapor will collect on the screen and then drip back into the oil filler when the engine is turned off. It seems to work as my engine won't even run with the oil filler tube connected directly to the right side carburetor. There was so much oil vapor that the engine would fould the plugs and die. I do not have that problem now and the engine runs just fine.

This is the same concept as the CB version.

Reply to
Brian Turner

Just remove the foam. The box must be mounted high enough that the oil collected in there can gravity feed back to the engine. Mounting the box low is a no-no.

John Aircooled.Net Inc.

Reply to
John Connolly

If the box is not sealed, then the intake vacuum doesn't make it to and help vent the crankcase, if I understand this process. The box is basically wide open if you don't seal it, and any vacuum from the carbs just pulls in air around the edge of the box and not much from the crankcase. Am I missing something here?

The concept here is that as the carbs draw in

Reply to
Bob

You are absolutely right. I did leave something out. I put a 1/4" pice of foam on top of the screening. It does not seal the box completely but it allows the carbs to pull the vapors from the breather.

Reply to
Brian Turner

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