1977 50 HP extension kit?

JoshOnt

Chief Petty Officer
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Aug 12, 2013
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I am re powering a new hull a got with my 77 merc 50 hp but have noticed that the shaft might be a bit short (maybe an inch?). So I am looking into an extension kit or another solution that is not replacing the motor.
 

racerone

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Dec 28, 2013
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It " looks " too short to you.--------How high is the transom ?----------Model # of the motor ?---------Pictures of the motor ?
 

JoshOnt

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Aug 12, 2013
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It " looks " too short to you.--------How high is the transom ?----------Model # of the motor ?---------Pictures of the motor ?
Yes looks, storing the new hull at someone's place and didn't have a tape measure. It is a 77 mercury 50 hp.
 

JoshOnt

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Aug 12, 2013
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Without pics can't help. there are no 1 inch extension kits.??
What do you need pics for? I said it is about an inch or two so anything in that ballpark will work I think. I am going to be doing some work to it so I could add some height to the transom if needed. I don't think I can drop it an inch or two.
 

jbcurt00

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You said it looks too short, maybe it looks that way to you, but isnt really.

Maybe it is maybe it isnt, until you put the motor on the boat and run it, it'll be tough for you to judge whether its too short, it'll run ok but could be better or will work just fine....

A pix would help someone wanting to give you advice, actually give you some that'll actually be helpful. But only if the motor in question is sitting on the transom of the boat you're referring to.

MT is right, there are no 1inch extensions kits. Nor 2inch.

Posting what boat and motor will help too. Boats have different hull designs, some have a pad directly in front of the motor and benefit from running the motor higher by an inch or so then would be whats considered normal mounting height.

Depending on the boat, motor and transom, adding height to raise the motor before you run it as is, may or may not produce better results then running it as is because you wont have a frame of reference. Perhaps raising the motor a half inch would be the 'sweet' spot.

If I was working on an outboard and needed to ask questions on an online forum, I would want racerone helping me. He knows quite a bit, and offered to help but had questions. You didnt answer them.

If you, do he could be a significant resource for you. As could anyone posting replies. None of us have to, we want to.

FYI. Some vintage boats dont have 15 or 20 inch transoms, they might have 17 or 18inch transoms. So neither short shaft or long shaft 'fits' just right or might look incorrect. They were run that way for decades by whoever bought them originally and performed just fine.

Look around, theres lots of info iboats forums. Lots of it would answer your questions so you would have more info on hand when you're looking and working on stuff.

Lets start w

Jack Plate

That might be a good way to go instead of raising thr transom

Or

Setback bracket

Best of luck w your projects
 

MTboatguy

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Jul 8, 2010
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Telling us experienced folks it is an inch to short, is just that, often times with the massive amount of different designs on boats over the years, there is a good chance one of us might have actually owned that very set up and can look at a glance and say yes or no it is alright. That is why people are always asking for images so we can look at it.
 

JoshOnt

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Aug 12, 2013
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Telling us experienced folks it is an inch to short, is just that, often times with the massive amount of different designs on boats over the years, there is a good chance one of us might have actually owned that very set up and can look at a glance and say yes or no it is alright. That is why people are always asking for images so we can look at it.
It is a thundercraft V142 best I can figure and I don't have images of the back so that is why I was asking why you wanted them. So maybe I could explainwhat it looks like.
 

Chinewalker

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Aug 19, 2001
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8,902
Bottom line is, if you need an extension, it's only going to come in a 5-inch flavor, meaning you may have to raise the motor to get it to proper height. Extension kits are rare. Might be better off either finding a long shaft motor, or a blown one similar to yours that you can rob parts from to make yours a long shaft.
 

Texasmark

Supreme Mariner
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Dec 20, 2005
Messages
14,778
If you don't understand what the guys have told you about 15" and 20" are just rough numbers where transoms are concerned, pull up some old catalogs, especially OMC and look at the relationship between the bottom of the boat and the AV plate on the engine. Interesting however, most of those in the pictures have the transom about an inch or so too short and the engine sits too low, putting excess drag on the rig.
 
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