Alpha1 lower unit removal

rebars1

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Feb 23, 2004
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1990 Alpha1: any tips on separating the lower unit from the upper unit? I have removed the front and rear nuts, loosened the four other nuts and have removed the zinc fin. The unit does not want to drop and seems stuck at the front bolt area. The rear portion has dropped about 1/4". I don't know much about the history of the unit, but it has been in salt water.
 

rebars1

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Feb 23, 2004
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Re: Alpha1 lower unit removal

can I place some wedges near the front bolt on both side and snug up the two rear nuts to try to pry the unit down at the front bolt (by pivotting it at the wedges), or will that put too much stress on the lower unit?
 

djvan

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May 3, 2003
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Re: Alpha1 lower unit removal

I don't remember for sure but I think there is a nut or bolt under the zinc fin that needs to be taken off. You may have done so already?

DougV>
 

Don S

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Re: Alpha1 lower unit removal

Since the back has dropped down, I guess you have the bolt under the trim zinc removed, in salt water corrosion builts up around that front stud. Heat will help.
I hate wedges between the housing, what I normally try to do is run the nuts on the side studs down as far as needed on a couple of prybars (aka large screwdrivers) and pry UP on the nuts. Don't push down or you could break the cavitation plate. It will probably damage the nuts, but they are replaceable.
 

rebars1

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Re: Alpha1 lower unit removal

I noticed that there is a brass oval shaped washer around the front bolt and is screwed to the housing with a Philips head screw. The front bolt might be hanging up on it. How does one get a screw driver and a hand in there to remove it? Is it OK to raise the drive up for better access?
 

Don S

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Re: Alpha1 lower unit removal

That is called a continuity washer, and is NOT your problem. Your problem is corrosion built up between the stud and the housing.
HEAT!!!!! And lots of it will get it apart. Then clean all the corrosion out of the hole, repaint all the burn marks and put some grease on the studs before you put it back together.
 

tommays

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Re: Alpha1 lower unit removal

IMHP you would find it a lot better to pull the compleat drive and set it up on a bench stand so you can work on it standing up :)


Tommays
 

bummy80

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Sep 23, 2006
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Re: Alpha1 lower unit removal

I just went through the same trouble, i posted a couple of weeks ago and recieved lots of tips and help. What i found that helped is i soaked everything i could with penetrating oil and heated around the studs and worked it up and down as much as i could and it finally just fell off. Mine was really tight took me a couple of hours just to brake it loose.Do a search under my name and you will find the thread.
 

rebars1

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Feb 23, 2004
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Re: Alpha1 lower unit removal

Thanks, bummy80, I had read your post before I started, but was trying to find it again. I am still stuck at the front bolt. I've tried heat and PB blaster. I will keep trying.
 

rebars1

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Re: Alpha1 lower unit removal

I pulled the whole outdrive off and put it on a stand. Tommays was right, it is easier to work on standing up. The good news is that the U joints and ring nut look to be brand new, no water in the bellows and the gimbal bearing feels OK.

The bad news is, I still can't get the lower unit to drop at the front nut even with heat, PB, and tapping down on the front stud.

Also, there was a lot of rusted metal flakes and chunks around the shift shaft, and I've been able to see some smaller pieces inside through the crack I've been able to open up. I assume they were from the old exhaust manifolds and risers, which I have already replaced.
 

rebars1

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744
Re: Alpha1 lower unit removal

Still stuck. Would it help to try to remove the front stud? Also, what happens to the shift shaft when the lower unit drops away?Could debris be wedging the shift shaft and preventing separation?
 

Don S

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Re: Alpha1 lower unit removal

IF you could turn the front stud enough to remove it, you wouldn't be stuck like you are.
You need heat, and lots of it. If you are using a propane torch for heat, it's not enough. You need big heat, get an Oxy/Act torch and heat it, it will come loose. The shift shaft stays in the upper and is brass on a stainless shaft and not your problem. You have aluminum housing corroded on the stainless stud. HEAT, HEAT, HEAT.
 

stevieray

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Jul 18, 2006
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Re: Alpha1 lower unit removal

The first time I took mine apart (1988 Alpha - was in brackish water for about 3 yrs), I had similar problem. What I did was put a small piece of flat bar on top of the 2 side nuts (the ones that don't have enough room to come off until the halves separate) & under the upper case. Then I cranked the nuts in the loosening direction, which forces the studs downward - working slow & being REAL careful not to damage the upper housing. Try that while applying the heat - it may just give the extra oomph you need to crack it loose.
 

stevieray

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Re: Alpha1 lower unit removal

Could be leavin's from anywhere in the exhaust path. Sorta common for that age & SW service. How did you do getting the upper & lower separated? Try my nuts idea?
 

Bondo

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Re: Alpha1 lower unit removal

Man,.............. That's Nasty.......................

The Fish aren't as Big,.... But I Sure Do Love living on a Sweetwater Sea..............
 

Bondo

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Re: Alpha1 lower unit removal

rebars1 said:
I am just nervous about lots of heat...seems like it would warp the housings.

It's Aluminum,.......... It Won't Warp............

IF you could get Enough Heat into it,.......
It'll Melt,+ Run,.....Not Warp...........
And,.... That would take ALOT of HEAT.............
 

Drrockter

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May 12, 2006
Messages
105
Re: Alpha1 lower unit removal

From what I have seen, if Don S. says max the heat, I would do it. If it would damage something he wouldn't have said it.
 

rebars1

Senior Chief Petty Officer
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Feb 23, 2004
Messages
744
Re: Alpha1 lower unit removal

Update: Using the heat and stevieray's method I was able to open the front end up about 3/16". I'll keep at it...it's got to give soon. More heat!
 
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