YAMAHA THERMOSTAT COVER GASKET 676-12414-A0

Function and technical context

This thermostat cover gasket acts as a sealing element in the cooling system of Yamaha engines, hermetically sealing the thermostat cover to prevent coolant leaks. The thermostat is a critical component that regulates the flow of water through the engine, keeping it at the optimal operating temperature while cruising. A deteriorated gasket causes coolant leaks, salt water entry into the internal circuits of the propeller and, consequently, accelerated corrosion and overheating of the engine in high sea conditions.

When to replace this part?

The thermostat cover gaskets show progressive wear due to aging of the elastomer and repeated thermal cycles; The main symptoms are visible drips around the thermostat cover, gradual loss of coolant level without apparent cause, and presence of moisture in the engine crankcase. It is recommended to check the condition of this gasket during each seasonal maintenance and replace it preventively every 4 to 5 years or when permanent compression, cracks or loss of flexibility of the elastomer is detected. Replacing the gasket preventively avoids costly repairs resulting from overheating and corrosion at sea.

Engine Compatibility

Equivalent manufacturer part numbers