BMW Repair: Vaccume Leak intake at the oil cover, hook ups, pcv system

Question
After changing an engine in my 1994, 740 BMW their was a vacuum intake into the oil cover, don't know if this is correct, it was not their on the old engine. please help. Lennox

Answer
When changing an engine from one car to another it is best to use all hook ups as they were on the original motor.Many times year and months matter how the engine is controled. So you may be changing the intake,oil pan,or misc brackets.All vaccum hook ups should be the same as original system.Your basically using just the long block(cyl heads and block).BMW's have a closed pcv system,by taking the oil cover off when running you will notice some vaccum and the engine will run rough,so make sure it has a good oil cap and tight dip stick.Seals/ gasket that leak will also cause drivability issues.