I would pull the top cover off and take a look before you even drop the lower or pull it off the boat. The upper gears go away really fast if the drive is low on oil.

In any case if the gears are good turn the prop and see if the gears turn. If no - most likely broken vertical shaft, if yes - most likely coupler. As pointed out any of the 3 will cause your symptoms.

Thank you all of you for the replies I am gonna investigate this weekend and I will report back to all of you. Thank you all so much

If you think it might be a coupler, there's an easy was way to check before you start removing lower unit. Stick your finger down where input shaft goes into coupler if you come out with aluminum flakes or gooie rubber on your finger most likely spline on couple is stripped out or spoon ( not good grease, there should be grease on spline) Some boat you can get back there with flashlight and see all the shinny flakes.

I'm back... Finally go around to looking g into my boat. And it is the upper gears are shot and gone lol! Guess I'm going to be looking for another good used drive or go s.e.i. like I did on the other side

Alpha 1 gen 1 1.5 ratios im in Tennessee if anyone has a lead on one maybe? Thank you all for all of your help and suggestions. I pulled the top inspection plate and that told me everything lol!!

craigs and ebay. gen 1 alphas are everywhere. sounds like you just need the upper, but obviously check the lower out too. count the gear teeth. (what's left of them.)

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