Alpha 1 Lower unit. Can’t turn shaft while reinstalling

Rhadley

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Trying to reinstall lower unit but hits hard stop about half inch before mating. Tried to rotate prop to turn shaft but it won’t turn. Any idea why? Lower unit has been off fir 3 months.
Thanks
 

Scott06

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Trying to reinstall lower unit but hits hard stop about half inch before mating. Tried to rotate prop to turn shaft but it won’t turn. Any idea why? Lower unit has been off fir 3 months.
Thanks
Probably not in gear . When shift lever is in fwd prop must be held ccw. Turn it ccw, should stay in gear to twist drive shaft and line up splines
 

alldodge

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Sounds like you split the drive and left the upper attached to the boat.

Agree with Scott and add, move your shifter to forward. Rotate shift shaft so prop locks in the CCW direction. Now install lower
 

Rhadley

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Probably not in gear . When shift lever is in fwd prop must be held ccw. Turn it ccw, should stay in gear to twist drive shaft and line up splines
I have the shifter in fwd and the prop rotated ccw. I can’t turn the prop to rotate the splined shaft-it won’t budge. I had replaced the impellor 3 months ago. Could it be friction of impellor?
 

Rhadley

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I have the shifter in fwd and the prop rotated ccw. I can’t turn the prop to rotate the splined shaft-it won’t budge. I had replaced the impellor 3 months ago. Could it be friction of impellor?
Note: the prop turns freely when the shifter is out of gear. I did push down on the spring loaded pin sticking up out of the drive shaft a bunch of times to loosen it up. Could it jamb the gears down in the lower unit?
 

alldodge

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ok trying to turn prop CCW is trying to rotate the impeller backwards is won't work. Use a pair of vice grips or large channel locks and rotate shaft with pin on it CCW just ever so slightly then try again. This may give you enough to slide it together

Either that or the water tube is not lining up
 

Rhadley

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how tight did you tighten down the 3 nuts
I took off the nuts holding the impellor cover on and lifted it. Prop still won’t turn shaft. Also won’t turn it CW when in reverse. Think i could damage anything if i forced the prop to turn too much?
 

crazy charlie

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Did you service the impeller??? sounds like that could have been done incorrectly.Put the lower on a bench and see if the prop turns when in gear. it should turn easily.If not then work backwards and remove the water pump cover and impeller..Charlie
 

Scott06

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I took off the nuts holding the impellor cover on and lifted it. Prop still won’t turn shaft. Also won’t turn it CW when in reverse. Think i could damage anything if i forced the prop to turn too much?
is it in gear or neutral? the shift shaft splines on lower mesh with the shoe in the upper with pliers turn the one in lower clockwise till it wont turn more (doesn't take a bunch of force) it will be in fwd. need it in fwd and the shoe in upper face toward bow when u reassemble.
 

Rhadley

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is it in gear or neutral? the shift shaft splines on lower mesh with the shoe in the upper with pliers turn the one in lower clockwise till it wont turn more (doesn't take a bunch of force) it will be in fwd. need it in fwd and the shoe in upper face toward bow when u reassemble.
Did you service the impeller??? sounds like that could have been done incorrectly.Put the lower on a bench and see if the prop turns when in gear. it should turn easily.If not then work backwards and remove the water pump cover and impeller..Charlie
No, i did not do anything with the prop, just changed impellor. I have done this several times before without issue. Prop turns easily in gear and out. What stops the shaft from rotating when the prop is turned?
 

alldodge

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The drive shaft won’t turn even if it is in neutral.
While it's hard to turn it should turn. The resistance is coming from the impeller only. If it won't turn no matter what then need to remove the impeller and if it still won't turn there are other problems
 

Rhadley

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Removing the impeller does not allow the drive shaft to freely turn in neutral. I can get it to rotate about 1/8 of a turn or less. This lower unit has been sitting with oil drained for 3 months. Is it possible there is corrosion inside? It would still have a coating i would think since it is so thick.
 

Bt Doctur

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Aug 29, 2004
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rusted up bearing or races in the driveshaft ,the usual culprit is the roller bearing above the pinion gear ,upper shaft bearing not so much
 

alldodge

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Just installed a brand new SEI alpha drive yesterday. It came down about an inch above so I rotated the upper drive shaft by hand and then it dropped to a hard stop about a 1/2 above flush. Removed and retried a few times then realized it was at the height of the alignment pins.

Being a new drive it turned out to be paint, so used a rubber mallet and just some light tapping brought it together
 

tank1949

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ok trying to turn prop CCW is trying to rotate the impeller backwards is won't work. Use a pair of vice grips or large channel locks and rotate shaft with pin on it CCW just ever so slightly then try again. This may give you enough to slide it together

Either that or the water tube is not lining up
or jammed...
 

Rhadley

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Jul 20, 2003
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Check out the video. Does not sound like rusty bearing. It is a clear “clicking” like metal on metal.
 
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