This is a Mercury Marine thermostat housing assembly designed for select Mercury Verado 4-stroke outboard engines from 135 HP through 400 HP. The assembly is part of the engine's cooling system and houses the thermostat, which helps regulate engine operating temperature by controlling the flow of cooling water.

• Superseded By: 8M0174561
• Type: Thermostat Housing Assembly
• Engine: Verado 4-Stroke L4/L6
• Horsepower: 135–400 HP
• Thermostat Rating: 140°F / 60°C
• Interchange: Sierra 18-3631 / 18-3631-K

We recently acquired a large inventory of overstock items. These items are in manufacturer's original packaging and may have minor cosmetic blemishes from storage.