Is it possible to put the upper half of the sterndrive on first? Or do I need to put the whole drive on together?

1985 Century Mustang

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I went to mount the upper half of my sterndrive (Merc Alpha One Gen One). It's much easier for me to put the upper half on, first because it's lighter and way easier to maneuver. Is this possible to do it without assembling both halves? Your experiences and thoughts. Thanks
 

1985 Century Mustang

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Further,,, In some youtube videos I have watched them adjust the prop slightly, so it locks into the coupler, that's why I'm asking.
 

1985 Century Mustang

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I just gave it a dry run, but I couldn't get it to go in all the way. Yes the engine is aligned nicely with the alignment tool. It goes all the way in the coupler and spins freely with 2 fingers. There's spline grease on the tool. So I know it's aligned.

So I'm thinking maybe the whole drive needs to be put together to do this.
 

tpenfield

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It is often tricky to get the gimbal bearing to align (pivot) so that the drive shaft meets the coupler properly. I often grab the u-joints (to the extent that I can reach them) to help the drive shaft find its way.
 

1985 Century Mustang

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It is often tricky to get the gimbal bearing to align (pivot) so that the drive shaft meets the coupler properly. I often grab the u-joints (to the extent that I can reach them) to help the drive shaft find its way.
So have you done it with just the upper half on?
 

Dubed

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Assemble it on a stand, vice, saw horse and 2x4s or whatever you have so you can pay attention to easily lining it up and mating the 2 halves properly. Doing this while upper is on the boat is a sure fire way of destroying the oil seal in the upper. (Ask me how I know)
Turn shift shaft clockwise and prop counter clockwise till it solidly locks in gear. Use a bungee to wrap around the prop a couple times and hook to the upper with good tension to keep it locked while installing. Make sure your remote is in forward.
I use a some cribbage on the driveway to stand it on at the right height to align the driveshaft with the gimbal and install. That takes "most" of the lifting out of play.
It's a PITA but you can certainly do it if this old man can 😉
 

Stinnett21

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Since you won't have the prop to reposition the shaft you can bump the starter to reposition the coupler. But frankly that method is still a PITA. With my A1G2 it's best to remove and install the entire leg. Yes it's heavy so you have to position the boat on the trailer so that the leg sits on the skeg taking the weight. Or better yet, build a cart to the height that suits your needs. With it sitting on my homemade cart, which is on wheels, I shove it in while playing with the propshaft. It's a very close tolerance, as it should be, so a very slight adjustment of the shaft is often all that's needed. Almost to the point of not even realizing you moved it at all.
 

Scott06

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You will have two issues doing it in halves- rotating the driveshaft to index with the coupler and aligning the shift shaft shoe between upper and lower.

I used to move the front of my trailer up /down so that I can put the skeg on a boat and have the driveshaft be at right height to go in bellows and gimbal.
 

1985 Century Mustang

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Assemble it on a stand, vice, saw horse and 2x4s or whatever you have so you can pay attention to easily lining it up and mating the 2 halves properly. Doing this while upper is on the boat is a sure fire way of destroying the oil seal in the upper. (Ask me how I know)
Turn shift shaft clockwise and prop counter clockwise till it solidly locks in gear. Use a bungee to wrap around the prop a couple times and hook to the upper with good tension to keep it locked while installing. Make sure your remote is in forward.
I use a some cribbage on the driveway to stand it on at the right height to align the driveshaft with the gimbal and install. That takes "most" of the lifting out of play.
It's a PITA but you can certainly do it if this old man can 😉

Yeah I locked it. Thanks for the heads up.
 

1985 Century Mustang

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You will have two issues doing it in halves- rotating the driveshaft to index with the coupler and aligning the shift shaft shoe between upper and lower.

I used to move the front of my trailer up /down so that I can put the skeg on a boat and have the driveshaft be at right height to go in bellows and gimbal.

I just put the two halves together and I'm going to mount it that way as one. Now that it's aligned really good hopefully it won't be difficult. FWIW - It took me a lil while to get the halves together. Ughhhhh, this boat is really kicking my arse. Most likely tomorrow I'll mount the drive to the boat. It's starting to rain here in the east coast. The weather temps here have been unseasonably cool.
 
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dubs283

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The design of an mc-1, r/mr/alpha one, and gen 2 alpha drive does allow one to remove/install the gear case from the drive shaft housing with the drive assembly installed on the bell housing

I personally wouldn't attempt to install a fully removed alpha style drive via the drive shaft housing first then installing the gear case to the drive shaft housing. To me it doesn't make sense, it's much easier to reassemble the sterndrive unit on the stand and install the complete sterndrive to the bell housing

Fwiw, the last time I removed a gear case from a driveshaft housing with the complete drive installed was over 15 years ago. Much less trouble to remove/install the complete sterndrive assembly. Plus having the whole drive off gives a chance to further inspect vital components of the package, ymmv
 

1985 Century Mustang

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The design of an mc-1, r/mr/alpha one, and gen 2 alpha drive does allow one to remove/install the gear case from the drive shaft housing with the drive assembly installed on the bell housing

I personally wouldn't attempt to install a fully removed alpha style drive via the drive shaft housing first then installing the gear case to the drive shaft housing. To me it doesn't make sense, it's much easier to reassemble the sterndrive unit on the stand and install the complete sterndrive to the bell housing

Fwiw, the last time I removed a gear case from a driveshaft housing with the complete drive installed was over 15 years ago. Much less trouble to remove/install the complete sterndrive assembly. Plus having the whole drive off gives a chance to further inspect vital components of the package, ymmv

I totally agree, it was a real byatch to assemble both halves together off the boat/ bell housing, let alone putting the lower half onto the gear case onto the bell housing while it was on the transom. I couldn't even imagine doing it that way, as It would be incredibly difficult. A lesson surely learned. It's going on as a whole unit tomorrow.
 
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airshot

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I made a fixture with wheels to hold the whole outdrive out of some 2x4's, made the job much easier as I always removed my outdrive over the winter. Build it to the height that works best...
 
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