Prop won't spin. Not a hub issue.

[sea nympo]

I have a 1968 Starcraft with a 3.0 Mercruiser I/O. The engine runs great. Last trip out, we were trolling about 2mph. I popped it into neutral fo a second to make lures slow down. When I went back into gear, the rpm's went up like they should, but the boat didn't go forward. The prop wouldn't spin. Didn't hear any noises or feel anything in the boat. The shifter doesn't have a anything you have to hold to keep it in neutral. There is a separate lever for neutral throttle. The shifter works properly. I've checked that out. And it's not the hub either. Is there a cover over the input shaft? Because I don't see it spin when the engine runs. It still seems to be inline like it should be. If the teeth stripped, I would think I would have heard that? Any thoughts or ideas?

 

[alldodge]

With cables moving on the shift plate, then next check is to see if the lower shift cable is moving the shift foot on the drive. Trim the drive up and look to see if it moves when the cables moves

 

[Bondo]

I have a 1968 Starcraft with a 3.0 Mercruiser I/O. The engine runs great. Last trip out, we were trolling about 2mph. I popped it into neutral fo a second to make lures slow down. When I went back into gear, the rpm's went up like they should, but the boat didn't go forward. The prop wouldn't spin. Didn't hear any noises or feel anything in the boat. The shifter doesn't have a anything you have to hold to keep it in neutral. There is a separate lever for neutral throttle. The shifter works properly. I've checked that out. And it's not the hub either. Is there a cover over the input shaft? Because I don't see it spin when the engine runs. It still seems to be inline like it should be. If the teeth stripped, I would think I would have heard that? Any thoughts or ideas?

Ayuh,.... Welcome Aboard,..... No cover over the driveshaft, but only maybe an inch is exposed,....
Trollin' is tough on couplers, especially if the splines aren't greased every year,....
At trollin' speeds, the splines are constantly loading, 'n unloading, which grinds 'em to nothing without grease,...
Pull the drive, 'n look up in through the gimbel bearing, to see if that's yer problem,.....