Yanmar 124223-42092. Impeller

Fits: 2GM20F , 3GM30F , 1983-2005 freshwater cooled (antifreeze) models made in Japan. Will not fit 1997 and later  European made. ( the serial number will start with E on the European models)

3HM , 3HMF , 1980-83

3HM35 , 3HM35F , 1983-1992

Diameter: 50.8mm (2") 

Width: 22.1mm (7/8")

Shaft: 12.7mm (1/2")

6 Blades