RAV4. Engine Coolant Thermostat Gasket. Engine Coolant Thermostat Housing Seal. Engine Coolant Thermostat O-Ring. Engine Coolant Thermostat Seal. Gasket for Engine Coolant Water Inlet. O-Ring. Thermostat Housing Gasket. To 03/96. To 07/97. To 12/2008. Housing. hsng. O - Ring. Water Inlet. Water Neck.