I recently noticed my bilge was full of that milky water oil mixture. Couldnt find where it was coming from so I took it in. My guy said the automotive breather I installed with a foam filter had clogged up creating pressure. He pulled out the dipstick and said oil was coming out. Does this sound right? If so is there a bigger problem brewing because of this pressure. Note I only ran a few times before I noticed the oily bilge.
You need some type of crankcase ventilation or you will blow oil out of the tube and/or seals.
The factory setup (older) doesn't use a PCV valve and has hoses connected from the valve covers to the flame arrestor. The vacuum created by the air rushing into the arrestor during high-speed operation is enough to pull the air (and reduce pressure) in the crank case.
When switching to a larger flame arrestor or eliminating the hoses, there is no longer vacuum to pull vapors and reduce pressure, and then you end up with a mess.
You can keep the nice open element breather, but add a PCV valve to the other valve cover. You will be fine from there.
The bretahers have internal baffles to stop oil from blowing out.
You will find them on most of the well known engine builders engines.
Crank case pressure is normal and allot of the automotive type breathers and K&N breathers will collect oil in the mesh/filter element. When they are full the crank case pressure blows the oil out. They are meant to breath air, not oil. If your valve covers do not have baffles under them the problem is even worse.
Some people even go as far as puke tanks to collect the oil. Others will have problems with oil blowing out of the dip stick tube. One of the above on each valve cover will solve the problem.
It sounds like your oil is clean, so I doubt you have heating/cooling issues. Most motors will show small signs of milky oil on the underside of the valve covers since the engine heat dissipates before getting to the top of the valve cover (especially aluminum) As long as your engine gets to or above 145deg. when running, you are fine.
Weather doesnt look all that great, now I gotta run to Detroit to pick my boat up. Thats where the engine buliders located he warrantied it for me I called him with concerns that it was a rear main so he came and picked the boat up last Wed. Called yesterday to tell me oil came from my dumb a**, all in all he didnt sound happy hopefully I dont get stuck with a gas bill :confused1
Im planning on getting it Friday night, just head out after work. If Saturdays nice I`ll see ya out there.