Impeller Replacement - Putting lower unit back on

[qube84]

Hello, I tried to look through some other posts to see if I could find my answer before creating a redundant post but I couldn't find exactly what I was looking for. I have a V8 Mercruiser i/o Alpha 1 (late 90's) that I noticed wasn't moving water with muffs on so I assumed it was the impeller. I bought a kit and thought I did pretty good with putting it back together but I don't think the shaft is lined up correctly. The prop spins freely and it won't engage into gear. Is there a trick to making sure that the shaft is inserted correctly or did I possibly mess something up with the impeller install? I have not put gear oil back in since I'm guessing that I need to drop the lower unit back down again. Thanks for any advice you can give.

 

[havoc_squad]

Drive must be put in forward gear when servicing lower unit with the upper gearcase still attached to the boat.

Remove lower unit, put drive in forward, move the shift arm on the lower unit to forward position.

If uncertain which direction, it will be the direction the shift fork is on the back of the outdrive where the upper is.

I would need to look at the manual on which gear it must be in for removing the entire outdrive, as it has been a long while since I touch an Alpha One Gen 2.

You will know if it is on correctly or not with the splines, as there is no way to put the lower back in flush with the upper if its wrong.

What you do have to pay attention to is verify the water pump tube and hole line up properly, verify the drive lube hole o-ring in good condition is in place, and keep that plastic shield in place.

If it won't align on the splines, you'll need to turn the shaft the proper direction based on the rotation label ed for the outdrive. There are regular rotation and counter rotation drives that exist.

 

[qube84]

Thank you for the very detailed response! I'll try that when I can get back at it in a few days.

 

[Bt Doctur]

Sounds more like an Alpha 1 because the GEN II is impossible to mess up

 

[havoc_squad]

Sounds more like an Alpha 1 because the GEN II is impossible to mess up

Someone sticking in a Gen 1 to remove a OMC Cobra or Volvo Penta drive system is about the only way I could see that to be possible for a "late 1990's" one.

The outdrive serial number would put all those questions to bed.

 

[Bt Doctur]

 

[Bt Doctur]