Sierra 18-3553 Marine Thermostat 143°F for Mercury Outboard Engines

The Sierra 18-3553 is a marine thermostat designed for Mercury outboard engines with a 143°F temperature rating. This thermostat fits 7.5HP through Magnum II series engines, providing precise temperature control to ensure optimal engine performance and efficiency.

Key Features:

• 143°F temperature rating for precise engine cooling control
• Meets or exceeds original equipment specifications
• Designed specifically for Mercury Marine applications
• Direct replacement for easy installation

OEM Cross-References:

• Mercury Marine: 62981, 66850, 75692, 75692B
• GLM: 13010
• Mallory: 9-43019

Sierra Marine products are engineered to surpass high horsepower engine demands and stand up to harsh marine environments, meeting or exceeding the original equipment part they replace. A properly functioning thermostat is essential for maintaining engine temperature within the optimal operating range, preventing overheating and ensuring reliable performance on the water.