1993 v4 Johnson 115 lower unit fitment??

searsnathan

Recruit
Joined
Nov 13, 2017
Messages
2
I have a 1993 johnson 115, 20" lower unit with a bad powerhead. I've been looking a a lot of motors on Craigslist anywhere from a 90hp-200hp. A lot of motors in the area are anywhere from 1983-2000. Most of them have 25"shafts my question is if I was was to buy a motor with a 25" lower unit. What outboards would be comparable with my existing lower unit?
Thanks in advance.
 

jbuote

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Aug 17, 2016
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1,001
Not entirely positive, but I'm pretty sure the shaft length isn't the big concern..
​As long as the lower unit has the bolt patterns, gear design etc to fit the midsection, and you have the correct length driveshaft (with correct # splines) then the lower unit will fit it.

​The lower unit isn't specific to shaft length. (as far as I know...)
Rather it's designed for HP ratings and years...

​I'm sure others will point you in the right direction, but I think the real question for you is:

As long as whatever I buy has the driveshaft of proper length for the midsection,
​What year and HP engines can I bolt my existing 93 115 lower unit onto?

(EDIT: ​Since you have a 20" now, if you buy a 25" you will have to worry about height of the engine and is the A/V plate in line with the hull bottom etc... If you have a 20" now, you can't just repower with a 25" without resetting mounting height etc...
​You may be better off holding out for a 20" that matches what you have now if it's on your boat you use...)

​I'll admit I could be wrong, and honestly don't know the answer to either question, but I think that might be the real question you're asking.
​If I completely misunderstood, then I apologize and please disregard this... :)
 
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Faztbullet

Supreme Mariner
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Mar 2, 2008
Messages
15,937
if I was was to buy a motor with a 25" lower unit. What outboards would be comparable with my existing lower unit?
Only V4 engines as driveshaft/shift rod length can be changed to 25"
 

racerone

Supreme Mariner
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Dec 28, 2013
Messages
39,270
In the early1990's there was a change in the way the driveshaft / crankshaft splines were sealed.------So if you buy an older motor to get the powerhead you will have to look at the end of the driveshaft to compare.-----The spline count is the same but arragement dimensions need to be looked at !!!!
 

V153

Lieutenant Commander
Joined
Apr 16, 2011
Messages
1,764
Seems to me we ran into a problem where the driveshaft on a newer case was a lil bit taller. And wouldn't let the lower fully seat. Easy fix, just grind some off top of the shaft.
 
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