mattmak wrote:
I managed to find a real 6J2 driveshaft. It is longer than the short 663 driveshaft pictured above by approx 18 to 20mm.
Matt, first off I want to thank you for posting the yamaha parts on this thread and for helping me locate a motor base plate for my twin cylinder yamaha.
I have been trying to put together a twin short shaft for years after I purchased a NOS power head. I didn't know at that time there were several versions of that power head and my power head was only produced for a year or two. Parts were almost impossible to locate let alone purchase.
THE DRIVE SHAFT ISSUEI never had a 15 inch twin drive shaft or complete lower unit. I only had complete 6J2 lower units. Two years ago I was ready to mount the motor. It would not mount! Drive shaft was too long. The 6J2 drive shaft will only work on the 70 hp. The two cylinder drive shaft will work on both. There is enough spline on the twin for the 70 hp. I got a new twin cylinder drive shaft from a Canadian dealer using the part number you posted. I now have a complete twin 15 inch lower unit. As for the difference between a 6J2 gear case casting and the twin. Only a minor difference. You can make the alteration very easy.