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Run a down pipe that extends submerged into the fuel mix in your tank from the barb for your recovered fuel back to tank.
You didn’t remove the reeds behind the cover plate did you?
You should not be getting a vapour cloud like that.
I did not remove the reeds behind the cover. Doing so would result in a back and forth pumping action as crankcase pressure goes negative and positive. With no reeds it would be a very busy little operation going on behind the reed valve cover as the two crankcase pressure/vacuum cycles are 180° out of phase.
We should be getting a vapor cloud. It is that way by design.
It is vapor pressure in the crankcase that pushes out the condensate after it pools. After all condensate is gone positive crankcase pressure on every downstroke releases some vapor.
When it is dark outside run a motor in a water tank and a flashlight will easily show the vapor coming from the recovery tank. At 1,000rpm the vapor plume is about a foot in length. Looks like fog. Highly flammable. I know of two other people who have crankcase drain recovery systems on 1950’s 35hp OMC’s and all three of us have seen the oily residue the vapor mix leaves behind on Feather Craft aluminum hulls as it condensates there.
I stand strong in my conviction that this phenomenon is being overlooked by many and is a hazard. This vapor plume is the same as the vapor that goes into the cylinder each stroke and is ignited by the spark plug.
If the vapor was not to be expected there would be no need for vapor separators on more recently designed OMC motors.