Having a spare lower unit narrows it down to a linkage problem, (providing it's not the strange conincidence of both l/u's having the same blown gear).
Have someone operate the binickle, while you watch the linkage at the motor.
It's really the easiest way to understand the workings. It
is all adjustable, as you will learn.
The manual will explain it,I can explain it. But trust me, you won't fathom it until you study the movement with your own eyes.
Not that it is strange or complicated. It's not. But---- "the thingy remains still,while the bracket thingy moves ,but only in forward"---isn't goin to help you as much.
So you have your mate move the binikle into forward,slowly, exhilerate, then back to neutral, and past neutral in reverse to the stop, back and forth like this with the motor shut off, until you understand it. If the binikle locks-up,and doesn't allow engaging, turn the flywheel by hand until it moves freely back and forth. Then with your mate's help, you can see how it werks much better than the manual or I could explain.
Where the manual
will help, is when it comes to the proper meathod of removal and installation of the lower unit. It must be in neutral when it is removed, and the shift shaft must be in neutral durring installation. Insure that once the l/u is seated and bolted-up, that it is still in neuutral, and the cogs didn't slide into gear durring the mating-up process. If it is in gear, you must drop the l/u and start from scratch.
My Motor goes forward/N/ but wont shift into reverse Mercury 650cc 65hp Thunderb
Linear Mode
