lower unit to upper shifter controls reversed

k24rz

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Jun 22, 2020
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i have a 1990 mercruiser 4.3 alpha one im trying to attack lower unit onto the upper and the mercruiser manual says to put the shifter into forward and to turn the lower unit shift shaft counter clockwise to engage forward after i assemble when i go to shift into reverse the upper unit shifter turns to the left but the lower unit needs to turn to the right to shift into reverse they are in opposite direction i spent 6 hours trying to play around with it i dont udnerstand why does the upper shifter turns the opposite direction when im engaged in forward it need to go right to engage reverse not left as the upper wants any help would really be appreciated
thanks
 

alldodge

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The manual is not clear
The bad is you need to remove the drive and slit it again

With drive separated rotate the shift shaft while rotating the prop counter clockwise until prop locks. Place a bungee cord or other on prop to keep it locked in CCW rotation

Now place top half on the lower half keeping the upper shift foot facing straight forward. Once together it can now be installed keeping the prop locked in the CCW direction

How I like to place the two halves together is up side down. Place top up side down and lower the lower half on the top half
 

k24rz

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Jun 22, 2020
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Rotate the shifter rod clockwise and prop counter clockwise ? That engages the reverse tho if the prop lovks while in reverse ?
 

k24rz

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Jun 22, 2020
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The prop needs to spin clockwise to push forward so how is it locking in reverse while shifter is all the way forward correct? im confused
 

k24rz

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And in which direction do i need to rotate the shaft while spining the prop counter clockwise?
 

alldodge

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The prop needs to spin clockwise to push forward so how is it locking in reverse while shifter is all the way forward correct? im confused

The drive uses a dog type clutch so it locks in place in the opposite direct by hand. So when prop locks in CCW direction that is forward, and CW for reverse

Don't remember wich way but makes no difference so long as when the shaft is turned it locks the prop in CCW direction. While locked, you can turn the prop CW and it will click as it turns
 
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