I’ve a Bavaria 30 buit in 2007 which I purchased in 2008. Ever since the vessel has been in my possession I’ve noticed that transmission oil escapes from the oil filler of the saildrive. I’ve checked the O ring seal and it appears to be in good condition, but any prolonged use of the engine appears to result in a heavy discharge of oil from the filler. I had thought that perhaps there was too much oil in the casing, hence increased pressure and forcing out of the oil, but I’ve always checked the oil level in accordance with the instructions in the manual which categorically states that the dipstick should be left unscrewed when checking the level. I know another Bavaria 30 owner has exactly the same problem with his saildrive. Can anyone shed any light on the problem and how it can be remedied.
I have noticed that after use there is pressure in the saildrive of our Bav 36. This happens if I remove the filler plug when the oil is warm, you can here the air coming out. I have often wondered why Volvo did not put in a breather like you get in most car gearboxes? Again I wondered if our “breather” had got blocked up! We only get a slight weep of oil from our saildrive.
However the good thing is that if there is pressure in the saildrive the seals at the bottom can’t be leaking! On the other hand I have thought that if you check the oil in the saildrive when it is hot and it then cools down it will produce a vacuum which could draw in some sea water past the seals! So now I only take out the filler plug when the saildrive is cold.