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Alpha One Gen 1 Lower Shift Issues after water pump replacement

S

SeaWutDevelops

New member
Hello, I recently replaced the water pump in my Alpha One Gen I. I did this by removing the Lower Unit only. After mating the lower unit back on, I was not able to shift from forward to neutral (I kept the drive in forward per recommendations from the forums). I bolted up everything tight and did not align the u-shaped shift piece to the bronze shift arm that mates with it. (please see attached picture).
First question, would bolting up the lower unit with the bronze shift arm not aligned properly to the u-shaped shift piece cause damage to the u-shaped shift part (it seems a little bent...see picture)?

There were no issues shifting the boat previously.
IMG_3138.jpg
Now after removing the lower unit again and trying to align the shifting parts, there seems to be too much of a gap between the bronze arm and the u-shaped piece. It will shift into forward and neutral but I cannot get it to go into reverse.

I made sure the stainless steel washer and washer gasket were installed on the shift shaft before installing the lower unit. The bronze shift coupler seems to have a lot of play in it (moves up and down a lot).

Any help would be greatly appreciated. There are no boat mechanics close to me and my boat is a 26' pontoon that is not fun to pull anywhere but towards the lake.

Thanks guys.
 
Well lets see. You will need to remove the lower unit again to verify it did not suffer any damage.
Using a socket of the correct size on the splined shaft try to see if it still moves freely and engages F and R

Remove the upper unit next, no need to be in any gear to remove it. You will need to remove the SS pin in the shift arm to drop the bent one out of the housing , install the new arm , install the pin.
If you cannot remove the old pin, drill a hole in the arm to crack it off the shaft and save the pin.I have extra arms , I can send you one

If you did everything wrong you crushed the selector in the lower unit, that will require dis-assembly on the lower to make repairs

manual links to follow shortly http://www.boatfix.com/merc/Servmanl/6/6B4R3.PDF
 
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The way its gone is:IF DROPPING THE JUST THE LOWER
lube the impeller, grease the shaft,turn splined shaft fully clockwise untill prop is locked CCW. install lower by lining up the water guide tube and turning the prop CCW about an inch to line the splines of the driveshaft. You`ll feel it engage, START THE FRONT NUT WITH 2 TURNS to hold the unit in place.
move brass lower shoe so that it goes on to the lower splined shaft and is facing in a straight line
install the 2 side nuts MAKING SURE THE LOWER SPLINED SHAFT MOVES UP AN DOWN .
tighten the side nuts , the bottom nuts the front nut and the allen under the zinc

Best way is to put the lower in a stand and install the upper unit on the lower.
Turn splined shaft fully CW untill prop locks CCW
lower upper unit and make sure the copper tube enters the giude
turn lower brass shoe to engage the splined shaft and is in a straight line.
turn input shaft slightly to mate the driveshaft , you`ll feel it drop into place
You may have to split the unit slightly with a screwdriver(raise it up ) to start the 2 side nuts untill tight
install remaining nuts and hardware
Dont forget the small O ring between the units
 
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