Quicksilver 866775 Big Block EC Exhaust Catalyst Retaining Rings MerCruiser

These retaining rings secure the exhaust catalyst elements within the exhaust manifold assembly, ensuring the catalysts remain properly positioned for optimal emission control performance.

The MerCruiser EC (Emission Control) exhaust system features an integrated catalytic converter design that significantly reduces exhaust emissions and virtually eliminates exhaust fume odor. The retaining rings are a critical hardware component that holds the catalyst in place within the manifold — proper seating is essential to prevent catalyst movement or damage during engine operation.

Key Features:

• OEM Quicksilver replacement retaining rings for MerCruiser big block EC exhaust systems
• Secures the exhaust catalyst within the exhaust manifold assembly
• Manufactured to Mercury Marine original equipment specifications
• Supports the EC catalyst system's ultra-low exhaust emission function
• Direct OEM replacement — no modification required
• Part Number: 866775

These retaining rings are a recommended replacement item whenever the exhaust catalyst or exhaust manifold is serviced on big block EC-equipped MerCruiser engines. Using genuine Quicksilver OEM hardware ensures proper fit and maintains the integrity of the emission control system.