Originally Posted by tonup69
One more pre-rebuild shot. See those intermeshed gears at the bottom of the inner gearbox cover? Those drive the tach. I think this is a 1964 only design. These parts are not in the '64 or '65 book, so I really wanted to keep this - and I also have the rare counter-clockwise tach which I had re-built.
That is the speedometer drive, not tach drive. It is a carry-over from the pre unit design transmission. The tach drive for that motor should be on the left, front side of the motor, and is driven by the exhaust cam.
Here is a pic of a pre unit trans, but with the speedo drive removed and plugged. BTW, welcome to the jj from another Mid-Southerner