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Re-assemble Alpha One lower unit...

I

Iowa Mike

New member
I've got a 1987 Rinker with the 5.0 200 hp chevy V8 and the Mercruiser Alpha One Gen 1 sterndrive. I changed the water pump, impeller, etc and tried to put the stern drive's lower half back on but something's stopping it from going all the way up. It seems like the drive shaft's splines aren't messing up inside. I pull it down a bit and turn the prop just a hair but still no go. I tried this at least 10 times now and I took a break. I can see that the studs are up through their guide holes to where I can see the tops of them. The shifter shaft isn't hanging up either but something's definitely hitting somewhere cause i can feel it. I greased up the driveshaft at the splines and I can see it's hitting but not going in. So, what am I doing wrong or what's the trick to get it all the way on?
 
Drive is in forward, right? So the prop is locked in the counter clockwise direction, and throttle is in full forward position

If all true, recheck the water tube
 
with the control box in full fwd, the lower splined shaft turned fully CLOCKWISE for fwd gear.then lower the upper unit while turning the brass shoe clockwise and stopping when at a straight line.upper should drop down. Now the tricky part, slightly raise the upper start the 2 side nuts and snug them down. With the prop shaft locked counterclockwise the brass shift show should be facing in the 12:00 position exactly
 
"""It seems like the drive shaft's splines aren't messing up inside. I pull it down a bit and turn the prop just a hair but still no go."""

When you install lower to upper and the splines are not aligned, Turn the prop C'Clockwise until they do. Then you will be able to push it higher to get nuts started. This is not the easiest or best method of doing service (Leaving drive attached and only lowering/removing lower unit). Reassembly is more difficult

Dont try to move the lower downwards wards and guess on spline alignment. Turn prop shaft at the same time while pushing it up.

If you had the entire drive off and in a service stand the lower would be clamped down and you would be removing the upper to service the water pump/lower unit. When putting the two half back together you would align water tube, align vertical drive shaft, align shift arm to12:00 and lower upper down. If it did not go all the way you turn prop shaft C'Clockwise and it will literally drop down once splines align.
 
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