1977 SS 18' transom height

[El Gaffer]

Can anyone tell me the transom height on a 1977 SS 18ft outboard?
I have a I/O and about to mount a offshore bracket, I found a basic equation but need that measurement to base it off.
Thanks

 

[Watermann]

Standard for a long shaft motor transom is 20"

 

[GA_Boater]

When using a bracket, motor height is higher than a transom mounted motor.

 

[El Gaffer]

Thanks.
Seems like most say 1" up for every 12" back, I also read 1/4" up for every 1" back. I also read 1.5" up for every 12" back, haha.
Anyone here have a recommendation on this? Have tomorrow off and its gonna be nice for January so gonna try to at least hold it up and get a eye on it.

 

[Watermann]

I'd follow the 1" up for 12" back, worked for my CMC set back.

 

[El Gaffer]

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[El Gaffer]

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[El Gaffer]

This was the result from the other day. The motor in the background is 25" shaft. I bolted up to the old transom to make sure the height is right. I plan to hang the motor here pretty quick. I was told to have the cavitation plate 3" above the bottom. Does that sound right?
The bracket was bought from a guy for cheap. Never used but made for a different boat. The degree is the same but it sticks out 2 5" on each side. Do you think that will create much drag?

 

[El Gaffer]

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[Watermann]

Looks like to me in the pic all that protrudes in the swim platform not the motor pod so I think it's fine since it'll be above the waterline Seems about right being 3" if the pad set back is close to 3', looks more like 2' to me but you don't want it too high.

 

[El Gaffer]

Ok. Sounds good. I will take a pic after I hang the motor to see what you think.
Thanks

 

[GA_Boater]

What are you doing inside the hull to support the bracket and motor?

Also you can add more than one pic with text. Bouncing around to read and back to the pics is very confusing. Look how Watermann is writing and showing pics in the same post.

 

[El Gaffer]

I have trouble posting pics here since they are too big of file, so I screenshot them. How do you guys do it?
I plan to use 5/8th stainless bolts from bracket thru transom and thru and aluminum plate (6"tall) spanning the width. I will tie that plate to the bulkheads. I will bolt 2 knee braces down to the stringers. The wood support that the old doghouse was hinged to has already been replaced with 1/4" aluminum flat stock. I will also bolt aluminum bracing from transom to that, pretty much how it was done with wood before.
I hope this will be enough, but I've never done this before.
I will be hanging a Johnson 150 and Johnson 9.9 off the back.
I have been kicking around making the transom flat across the top instead of convex. I will be standing and walking and moving to swim platform on that area will the old motor vents. I do like the look of the convex better and not sure if it being flat would hold water. I would like to mount a very short pedestal seat up there too.
Thoughts?

 

[Watermann]

Knee braces are a must with an OB config so that's great you plan on it.

You can have a flat transom cover and make you a back deck, no trouble there I see.

 

[Watermann]

For pics, this is my tutorial how I post my rebuild pics

https://forums.iboats.com/forum/oth...for-photo-attachments?p=10449178#post10449178

 

[El Gaffer]

Ok. I will read up on that. I mentioned it before in the Starcraft picture thread. I had alot of pics of the day I brought it home and tear down but I lost those. I will take some current pics and post them.
Thanks for the insight, I do think a flat deck will be safer if anything.

 

[El Gaffer]

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Figuring out this photo thing. Here is a pic from other day fitting windshields.

 

[Watermann]

Looks like you got it :thumb:

 

[El Gaffer]

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[El Gaffer]

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