Pre Alpha 1 228 lower unit install

Deep waters

Cadet
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My ignorance is not bliss. I did not put the drive in forward before removing the lower unit. As a result the prop shaft will not engage and I can't align the outdrive shaft to engage.
 

alldodge

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Welcome
If you just dropped the lower half of the drive, then no issue

Move throttle to forward
Rotate shift shaft until the prop locks in Reverse (note Rev not Fwd)
Raise the lower half into upper half
 

Deep waters

Cadet
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Thank you. I can't get the last 1/4" to marry. Also, while shaking it around to fit, the shift shaft is no longer in reverse. Your thoughts please?
 

alldodge

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The shift foot should be point forward on the upper half and should be held in position mated to the shift shaft on the bell housing

The prop isn't staying lock in rev so the shift shaft is moving. Could put it in position and then use a bungee cord on the prop to keep the prop locked in place

The splines on the lower shift shaft will mate with the upper shift foot, and it might hang on the 2 pieces if they don't align correctly. It can be done but sometimes it just not worth the trouble for me to save the gasket on the upper.

The easiest way I've found to do it is pull the upper, mate the lower with upper and than install drive
 

Bt Doctur

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All Dodge, I think you meant shifting into full fwd at the control box and rotating the lower splined shaft fully clockwise into fwd ,that will lock the prop in a CCW position not reverse
 

alldodge

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All Dodge, I think you meant shifting into full fwd at the control box and rotating the lower splined shaft fully clockwise into fwd ,that will lock the prop in a CCW position not reverse
I said it the way I did so I didn't need to explain anything about how the dog clutch works
 

Deep waters

Cadet
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Thank you for the good information. The shift shaft coupler is pointing port. I positioned the shift shaft to match. Does locking the prop in reverse still apply?
 

alldodge

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Shift shaft should point straight forward not to port

If the lower is in forward the prop will lock when prop is rotated counter clockwise
 

Deep waters

Cadet
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All is well for now. I haven't yet checked the shifting as I need someone at the throttle to help. In the mean time, now that lower and upper are mated, I need to remove and reinstall it. The bolt to hold the zinc fin fell out and rolled under my work bench. It's a good day! I get to practice.
 

Deep waters

Cadet
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Specifically rust and oil. 1975 Mercruiser Alpha MC1. If you can point me in the right direction I'd appreciate your insight.
 

Deep waters

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I'm sorry. I posted about difficulties with mating my lower unit to the upper. The information you provided was extremely helpful. I am impressed with the depth of your knowledge. It seems that I asked a question or for information unrelated to my initial inquiry which I shouldn't do.
As to your question, when I serviced the lower unit it had very grimy oil with large rust particles/flakes and I'm looking for some information about where the point of intrusion is.
I'm aware that the exhaust manifold is in bad need of replacement and will get that done when I am able. I gotta get this boat as ready, as good as she can be and on the water so that I can take two great grandsons fishing and maaayybe tubing. Time isn't on my side. What time I have left I'd like to spend it on the water with them as much as possible. Again, my apologies Sir, I will get the hang of this forum and be a better member.
 
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