If you have the Yanmar 3GM30f engine with the Kanzaki KM3-A tranny (2.61), the shaft is 1" . However, be very careful with the shaft length as it may vary ! A few years ago I had to replace the shaft on my 84 H34 and having picked up the specs right here on the site, I went to the prop shop and told them I wanted a 1 inch shaft, conical, 50.75 inches long. I almost got mad when the shop owner flat out refused to do it if I did not bring the old one. He knew what he was talking about ! I took the old one out, and it measured 54 inches. I humbly apologized to him.
So my advice is simple. Take the old one out if you need a new one, and bring it to a good prop and shaft shop in your area. Folks and marinas around you in Cranes Creek should be able to point you in the right direction to find one. Good luck
