Mercury Marine Water System Antifreeze

The Mercury Marine Water System Antifreeze (-46°C) is a high‑quality winterizing solution designed to protect marine engines and onboard water systems from freezing, cracking, and corrosion during off‑season storage. Formulated for reliable cold‑weather performance, it provides dependable freeze protection for outboards, sterndrives, inboards, and marine plumbing systems in moderate cold climates.

Features

• Non‑toxic 30% virgin propylene glycol formula
• Provides freeze‑burst protection to −50°F (−46°C) and freeze protection to 12–16°F (−11°C to −8°C)
• Prevents corrosion in aluminum, copper, brass, and soldered components
• Safe for rubber seals and hose materials
• Ready‑to‑use — no dilution required
• Compatible with:
  • Mercury outboard engines
  • Mercruiser inboard and sterndrive engines
  • Marine cooling systems 
  • Boats, PWCs and marine plumbing systems
• 1 gallon size (3.78L)

Product availability varies between locations, and some products are only available online. Please contact your nearest Martin Motor Sports here for availability.