What causes this?

 

What do you mean smoke?

 

Your engine may be building up oil gasses, and the breather is where it leaves the engine.

 

Yes, it indicates that you have blow by... meaning your rings or ringlands are either shot. Do you burn a lot of oil? Are you forced induction by any chance?

Excessive blow-by causes higher crankcase pressures. Turbo honda's experience this regularly. Under high load on a dyno you will see a lot of smoke blow out, but not heavy white... more like a white clearish type. That is why a oil catch can was invented.

 

it's normal, when oil gets warm it turns into gas.

 

I still don't burn a lot of oil, Thats why I am so confused. Yes I am turbo'd. My compression is still fine.

 

Time to buy a catchcan!

 

As long as you are not consuming oil at a rapid rate you should be ok. If you start blowing oil out of the breather, then you should be worried. If it is a faint amount of smoke while under high load, thats normal. If you are smoking at idle then that is enough to be concerned. Do a cylinder leakdown test and see what kind of numbers you yield. Compression tests aren't worth 2 cents in my opinion.

 

Get an Oil catch can Todd (ItzTw)

 

Its only smoking at idle on startup, then once its warm its fine. no oil comming out either..

 

you should be ok then..