Water Pump Impeller Gasket – Fits Yamaha 40HP 50HP 2-Stroke (Replaces 663-44315-A0) 28HP and carefully inspect the housing

and carefully inspect the housing for leaks

Product Type Thermostat Kit with Gasket and O-ring Installation Direct OEM replacement Fuel Type Gasoline Operating Temperature Thermostat opening temp: 150°F/65

While widely accepted

we recommend replacing the water pump impeller and related components every 300 operating hours or every 3 years

Reassemble the housing and lower unit

Water Pump Impeller Gasket – Fits Yamaha 40HP 50HP 2-Stroke (Replaces 663-44315-A0) 28HP and carefully inspect the housingProduct Details This Water Pump Impeller Gasket is engineered for Yamaha 2 stroke outboard engines including 40 HP (19841994), 50 HP (19841987), 50 HP Pro Series (19871990), and P50 models (19951996). Designed as a direct fit replacement, this gasket ensures reliable sealing between water pump components to maintain efficient cooling system performance. This gasket replaces Yamaha OEM part number 663 44315 A0. Critical seal for water pump impeller