ISO Yamaha 8hp high Thrust leg

[gungadin]

I am looking for a gearcase assembly for a 2005 Yamaha 8hp 4stroke. It is the high thrust model with the long shaft. A few notable things. The shaft from the top of the waterpump housing to the end of the splines that go into the head is 21 and ¾” long +/_. The diameter of the splines is as shown in the pictures. There are two shaft diameters at the top, I need the smaller one. My calipers show it approx. .475” as for the one I need. The shaft that is too large measures about .500”. If the shaft has a step down about 2” down from the top of the splines it is too large and won’t fit my engine. The gear ratio is about 3:1, so 3 turns of the drive shaft will turn the propshaft once. The other common ratio is about 2:1. Thank you

 

[gungadin]

Just an update if anyone is interested lol. In 2005 the gearcase driveshaft was a one of, every other year was the the larger diameter. . So trying to find one is very difficult to say the least. A driveshaft is 500$ new. Had to bite the bullet on this one, gearing et all is the same year to year though so ok there.