Keeping an engine running at the right temperature is critical for both performance and longevity, and the Mercury Thermostat Seal (25-8071341) plays a key role in making that happen. Designed for MCM/MIE GM V-6 and V-8 engines with closed cooling systems, this OEM seal ensures a tight fit, preventing coolant leaks and maintaining the efficiency of your thermostat assembly.

Built from durable, heat-resistant materials, this seal can handle the high-pressure demands of a marine engine’s cooling system. It’s specifically engineered for Vazer models (2007 & up) and GM-powered marine engines (1996 & up), providing a reliable solution for replacing worn or damaged seals. Whether performing routine maintenance or troubleshooting an overheating issue, a properly seated thermostat seal keeps coolant flowing where it’s needed.

Why It’s Important:

• Prevents Coolant Leaks – Keeps the cooling system sealed for consistent temperature regulation.
• Ensures Optimal Engine Performance – Helps prevent overheating and improves overall efficiency.
• OEM Precision Fit – Designed specifically for Mercury applications, eliminating guesswork.

Replacing a failing thermostat seal is a small fix that makes a big difference in engine health. A secure seal means better cooling, reduced risk of overheating, and a smoother ride every time you hit the water.