Thermostats | Honda Outboard

Shop Honda outboard thermostats designed to regulate engine temperature and maintain proper cooling system performance. A properly functioning thermostat helps your Honda engine warm up correctly, run efficiently, and avoid overheating or cold running conditions during maintenance and repair work.

Choosing the Right Honda Thermostat

Thermostats are model specific and temperature rated. Always confirm your exact Honda outboard model, horsepower, and serial number before ordering to ensure proper fitment and operating range.

• Correct temperature rating: installing the wrong thermostat can cause improper engine temperature and performance issues.
• Single or dual thermostat systems: some Honda outboards use multiple thermostats depending on engine design.
• Saltwater operation: corrosion and mineral buildup can cause thermostats to stick open or closed.
• Routine cooling system service: inspect thermostats whenever servicing the water pump or addressing overheating concerns.

Common Honda Thermostat Problems

• Engine overheating at idle: thermostat may be stuck closed or restricted by debris.
• Engine runs too cool: thermostat stuck open, causing poor fuel efficiency and incomplete warm up.
• Steam from exhaust relief ports: restricted coolant flow due to thermostat malfunction.
• Erratic temperature alarms: thermostat sticking intermittently due to corrosion or scale buildup.

When replacing a thermostat, inspect the gasket surface and housing for corrosion or debris. Proper installation and sealing are critical to maintaining stable engine temperature and long term reliability.

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