Mercury Marine / Mercruiser New Thermostat 8M0168892 8M0117413 Sierra 18-3640

Thermostat for Mercury Marine Mercruiser

This thermostat for Mercury Marine Mercruiser engines maintains precise engine temperature and cross-references OEM part numbers 8M0168892, 8M0117413, and Sierra 18-3640.

Overview

This marine thermostat is a direct replacement component for Mercury Marine and Mercruiser cooling systems. It regulates coolant flow to keep the engine operating within its ideal temperature range. This thermostat suits boat owners and mechanics performing routine cooling system maintenance.

Built For Performance

• Precision-engineered opening temperature for consistent cooling system performance
• Corrosion-resistant construction for long service life in marine environments
• OE-style design for reliable sealing and proper coolant flow
• Direct replacement fit for compatible Mercury Marine and Mercruiser engines
• Quality gasket surface finish helps prevent leaks after installation

On-The-Job Use

• Replacing a worn or stuck-open thermostat during cooling system service
• Maintaining optimal operating temperature in saltwater and freshwater boating
• Supporting routine engine maintenance schedules for marine powerplants
• Restoring proper warm-up time and temperature gauge accuracy

Specs At A Glance

Good To Know

Q: How does this thermostat affect engine operation? A: It regulates coolant flow so the engine reaches and holds the correct operating temperature, which supports efficient combustion and reduces wear.

Q: Can this thermostat be used in a MerCruiser stern drive? A: It is designed for Mercury Marine and MerCruiser applications that cross-reference these part numbers; verify your serial number and engine series before ordering.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.