Alpha 1 Gen 1 Sterndrive install

[FrMDL]

Hello all. I'm a new member and am rebuilding a 1989 Thundercraft with a 2.5 Mercruiser with a Gen 1 sterndrive.
I have everything back on the transom (it's been a total rebuild but not engine rebuild) and put the sterndrive on tonight. It gave me some trouble ( mistakenly greased the gaskets that go into the gimbal bearing - don't do this! It makes it hard to get on) but finally went in all the way.
My problem: in forward the prop will only spin clockwise, but not smoothly at all. In neutral and reverse the prop spins freely in both directions. I can move the shifter all the way forward and all the way in reverse but it's obviously not engaging in reverse.
I made sure every thing was lined up in forward and the lower shift cable is installed correctly (I double and triple checked). I did not take the sterndrive apart only took it off the back of the boat. Any help would be marvelous. Thanks.

 

[dubs283]

Never seen a gimbal bearing gasket, maybe you're referencing the drive/bell housing gasket? If so, yes that gasket goes on dry, however, grease will not affect performance

As long as you installed the drive proper, aligning the shift foot on the drive with the fork on the shaft in the bell housing you're close.

With a lower shift cable replacement you must adjust the lower cable proper. Locked in forward gear set the trunion to 6" between centers of the trunion and plastic end hole. Adjust the remote cable with the lever in forward detent to match, then turn the trunion four turns towards the end of the cable.

Verify neutral/reverse. If no reverse or no full engagement adjust stud for lower cable attachment to the middle of the slot and check again

Final check/adjustment to be performed with boat in the water

 

[Bondo]

Hello all. I'm a new member and am rebuilding a 1989 Thundercraft with a 2.5 Mercruiser with a Gen 1 sterndrive.
I have everything back on the transom (it's been a total rebuild but not engine rebuild) and put the sterndrive on tonight. It gave me some trouble ( mistakenly greased the gaskets that go into the gimbal bearing - don't do this! It makes it hard to get on) but finally went in all the way.
My problem: in forward the prop will only spin clockwise, but not smoothly at all. In neutral and reverse the prop spins freely in both directions. I can move the shifter all the way forward and all the way in reverse but it's obviously not engaging in reverse.
I made sure every thing was lined up in forward and the lower shift cable is installed correctly (I double and triple checked). I did not take the sterndrive apart only took it off the back of the boat. Any help would be marvelous. Thanks.

Ayuh,..... Welcome Aboard,...... My guess is, the prop shaft moved, 'n allowed it to shift to neutral as you mounted the drive,.....
I use a bungee strap 'round the prop shaft, to hold tension on the dog clutch, so it doesn't slip into neutral,.....

When done right, it should lock in one direction, 'n ratchet in the other, in both forward, 'n reverse,....
Spinnin' freely only in neutral,.....

 

[FrMDL]

Never seen a gimbal bearing gasket, maybe you're referencing the drive/bell housing gasket? If so, yes that gasket goes on dry, however, grease will not affect performance

As long as you installed the drive proper, aligning the shift foot on the drive with the fork on the shaft in the bell housing you're close.

With a lower shift cable replacement you must adjust the lower cable proper. Locked in forward gear set the trunion to 6" between centers of the trunion and plastic end hole. Adjust the remote cable with the lever in forward detent to match, then turn the trunion four turns towards the end of the cable.

Verify neutral/reverse. If no reverse or no full engagement adjust stud for lower cable attachment to the middle of the slot and check again

Final check/adjustment to be performed with boat in the water

Thanks for. The gaskets I was referring to are the two gaskets on the drive shaft that go inside the gimbal bearing. I greased those and it made for in your impossible removal. But I did get it back out, that is the stern drive.

Everything seems to be in proper order with the stern drive, I think my adjustments were off even though I had double checked them. I'm a handyman by trade, I should know to triple check and then check again. But I'm new to the boating world.

I think my chief problem was that I did not have the shift cable screwed all the way in to the bell housing. When I took it off I could see three, maybe 3 and 1/2 threads so I tightened that down. I won't be able to get back to it all till tomorrow, but I'll post results. Thanks.

 

[FrMDL]

Ayuh,..... Welcome Aboard,...... My guess is, the prop shaft moved, 'n allowed it to shift to neutral as you mounted the drive,.....
I use a bungee strap 'round the prop shaft, to hold tension on the dog clutch, so it doesn't slip into neutral,.....

When done right, it should lock in one direction, 'n ratchet in the other, in both forward, 'n reverse,....
Spinnin' freely only in neutral,.....

Yes, I noticed that it was easy to move because the stern drive is so heavy and it's easy to bump it. I think though, that I did not have the shift cable screwed all the way into the bell housing so it was not engaging reverse.

 

[FrMDL]

Thanks for thee help. The gaskets I was referring to are the two gaskets on the drive shaft that go inside the gimbal bearing. I greased those and it made for a near impossible removal. But I did get the sterndrive back off.

Everything seems to be in proper order with the stern drive, I think my adjustments were off even though I had double checked them. I'm a handyman by trade, I should know to triple check and then check again. But I'm new to the boating world.

I think my chief problem was that I did not have the shift cable screwed all the way in to the bell housing. When I took it off I could see three, maybe 3 and 1/2 threads so I tightened that down. I won't be able to get back to it all till tomorrow, but I'll post results. Thanks.

Sorry for all the typos! I'm doing speech to text and I didn't edit. Ugh.

 

[Scott06]

Thanks for. The gaskets I was referring to are the two gaskets on the drive shaft that go inside the gimbal bearing. I greased those and it made for in your impossible removal. But I did get it back out, that is the stern drive.

Everything seems to be in proper order with the stern drive, I think my adjustments were off even though I had double checked them. I'm a handyman by trade, I should know to triple check and then check again. But I'm new to the boating world.

I think my chief problem was that I did not have the shift cable screwed all the way in to the bell housing. When I took it off I could see three, maybe 3 and 1/2 threads so I tightened that down. I won't be able to get back to it all till tomorrow, but I'll post results. Thanks.

those orings can be a PITA to get the driveshaft in the gimbal - Also when checking alignment and trying to get the drive seated you can build up a lot of grease in the coupler making it harder. While you dont want to force anything sometimes a kick or a little persuasion on the back of the upper gets it seated home.

 

[FrMDL]

So all worked out. I was right - I didn't have the shift cable screwed in far enough on the bell housing. Also, by specs on the shift cable were off. Not by much, but enough.
The boat starts, idles, and goes into forward and reverse gears! Now to put in carpet, fix the fuel gauge, touch up gel coat, put in the seats.....

Thanks for y'all's help.