All Sierra products are equal to or better than the original equipment parts they are meant to replace.

THERMOSTAT from Sea Star Solutions 18-3668. This device controls the flow of a heat transfer fluid, turns on or off heating and cooling units, and maintains the proper temperature. The engine and radiator are kept apart until a certain minimum temperature is reached. If it weren't there, the engine would lose heat to the radiator continuously and take longer to warm up.

Key Features:

• Before the water gets too hot and overheats the outboard engine, it is able to escape.
• prevents heat transmission from the cylinder walls and head while regulating water temperature to enable for engine cooling.
• The thermostat meets or exceeds the manufacturer's requirements.
• It was made specifically with maritime engines in consideration.
• Contains one each of the following: one 18-2552 thermostat gasket cover, one 18-2553 thermostat gasket, one 18-2554 thermostat cover gasket, one 18-2917 thermostat housing gasket, one 18-3551 thermostat, and one 18-7173 O-Ring.
• Fits GM engines with normal cooling, V-6 and V-8 ( 1983 and newer).
• GLM 13390, Mallory 9-43150, and Mercruiser Stern Drive 807252Q4, 807252T4, and 807252T7 are all interchangeable.
• Rating for temperature: 142 °F

Specification:

• Brand: Sea Star Solutions
• SKU: 18-3668
• UPC: 030999316318
• Weight: 0.18 LBS
• Unit Of Measure: EA
• Alternate Products SKU: "75-03948", "18-3668"
• Manufacturer Part Number (MPN): 118-3668

Temperature Rating: 142°F

This product replaces:

47-3668, GLM13390, 18-3668D, AP3948, AP552, 3099931631, 30999316318, 9-43150, 92-13390D