Hello Gents, I have read a dozen threads on this and follwed the links but to no avail. My 19 y.o,'s 1989 240, is blowing oil from the filler cap and into the throttle body. So I did what I have always done and replaced the flame trap and the housing, removed and cleaned all the lines and replaced the vacuum hose. Took the breather box off, blew through it easily. Cleaned the TB with carb cleaner. Of course replaced the filler cap gasket. Did what one suggested and after removing the filler cap, disconnected the line from the Flame Trap at the TB and blew through it easily letting me know that there is no obstruction of air from the FT to the BB to the engine. HOWEVER, I am still getting oil blowing out from under the filler cap within a few minutes of the engine starting. I considered replacing the breather box but not sure what that would do as it looked clean as a whistle and had no build up and blew air through easily. Why, O why would it still blow oil out from the cap? Advice would be appreciated!

Bernie
1989 240 w/200k; 1992 240 w/200k; 1996 850 w/300k