Oil Separator Box

The oil separator box is also refered to as the oil trap and PCV breather box. Blow-by air inside the engine crankcase is full of oil mist: the PCV breather box separates the oil out, drains it back in to the oil pan, and vacuum draws the remaining air back in to the engine intake.

Over time, sludgy oil deposits can build up inside and eventually clog the separator box, particularly if oil changes are neglected or if your car sees lots of frequent, short trips or cold weather. If the separator box clogs, blow-by air has nowhere to go and builds up pressure inside the engine crankcase.

We suggest replacing your oil separator box and associated PCV hoses every few years as a preventative measure. Trust us, this is much cheaper than letting a clogged separator blow out all of your engine seals!