Sierra Marine Thermostat 183558

Temperature: 160 Degree Fahrenheit; Fits Volvo Penta/ OMC Stern Drive Engines

The Sierra Marine Thermostat 183558 is a replacement cooling-system component for compatible marine engine applications. It helps regulate engine operating temperature by controlling coolant flow through the cooling system as the engine warms. Maintaining the correct operating temperature supports dependable performance, efficient combustion, and proper protection of engine components during normal boating use. This thermostat is identified by Sierra Marine part number 183558 for application matching and service reference.
Use the Sierra Marine 183558 thermostat when servicing a compatible marine engine that shows signs of temperature-control problems, including running too cool, overheating, inconsistent temperature readings, or reduced cooling-system performance. A properly functioning thermostat helps the engine reach and maintain its intended operating range while managing coolant circulation under changing load conditions. Replacing a worn or malfunctioning thermostat can be an important part of routine cooling-system maintenance.
Before installation, compare the existing thermostat and service information with the Sierra Marine 183558 part number to confirm compatibility with the specific engine, model, and application. Inspect the thermostat housing, sealing surfaces, gasket, and related cooling-system components during service, and replace damaged sealing materials as needed. Follow the engine manufacturer’s installation procedures, coolant specifications, and torque requirements. After installation, refill or restore the cooling system according to the applicable service instructions and check carefully for leaks or abnormal temperature behavior.
Sierra Marine products are developed for marine service and are commonly selected by boat owners, technicians, and repair facilities for replacement maintenance. The 183558 thermostat provides a clearly identified service option for compatible applications without requiring modification to the cooling system. Proper application verification remains essential because thermostat specifications and