Moroso 85671 Small Body Air-Oil Separator PCV Catch Can Kit

The Moroso 85671 is a small body air-oil separator designed to plumb inline with your vehicle's PCV (Positive Crankcase Ventilation) system. It captures excess crankcase vapors, residual oil mist, and moisture before they can re-enter the intake tract — protecting your engine from detonation, carbon buildup, and oil deposits on intake valves and manifold surfaces.

From the factory, a vehicle's PCV system routes these contaminants directly back into the intake manifold, which can compromise performance and long-term engine durability. This is especially problematic in direct injection engines prone to carbon buildup and in forced induction applications where intercooler efficiency can be reduced. The Moroso air-oil separator eliminates this issue by intercepting and collecting those contaminants before they cause damage.

Key Features:

• Small body design — engineered for tighter engine compartments where space is limited
• Billet aluminum construction with internal baffling and cleanable mesh media for efficient oil mist capture
• Two-piece body unscrews easily for cleaning and maintenance
• Knurled bottom half for tool-free removal and reinstallation of the bottom cup
• Bottom drain with elbow fitting for virtually mess-free oil draining
• Includes 3/8" 90° brass inlet and outlet fittings, 60" of 3/8" PCV/fuel vapor rubber hose, a billet aluminum mounting clamp, and a stainless steel mounting bracket
• Billet aluminum body can be polished, chromed, or powder coated for a custom appearance

The Moroso 85671 air-oil separator installs inline in the PCV hose routing and is suited for a wide range of street performance and racing applications. It is part of Moroso's universal small body air-oil separator lineup, available in black anodized or polished clear finishes.