280SL Engine oil discharge

[bogeyman]

I have the opportunity to buy an original engine out of a 280SL.
Owner claims it was running OK but was pushing oil out of the dipstick.
Any ideas what might cause this or what I might look for?

[Benz Dr.]

The crankcase needs to be vented or this will happen. Good chance the line going from the valve cover to the throttle valve is plugged.

[jaymanek]

Benz Dr is far more experienced than I, but from my experience of modern engines, excess crankcase pressure could indicate bottom end issues.

[Benz Dr.]

I can't disagree with that but I started with something easy. I've seen some really worn out engines and nothing was coming out of the dip stick. Look for an obsruction first and then do a compression test.

[Garry]

I have a similar problem on a 230 Auto that I am going to look at on Wednesday where there appears to be oil venting from the dipstick.  Would the good Dr suggest to check the same problem as the 280 engine in this thread? Meanwhile I will see if I can get a compression check done tomorrow.

Garry

[Benz Dr.]

If you have the early 230Sl dip stick with the filter, then it's possible for excess crank case pressure to be vented through the tube. Later engines won't have this filter on the dip stick and all venting is done through the line on top of the valve cover.
Early 230 engines have a smaller port on the throttle body than the later engines probably because all crank case venting is routed through this system. Since the throttle valve is closed at idle, any real pressure build up won't be drawn away quickly enough and you may find that oil is being forced out through seals or cracks in gaskets. If you have that much blow by, it could be pointing to a bigger problem. 

[Garry]

It is a very early engine I think, I believe the car was a June 1963!