Will my 73 135hp lower unit fit on my 77 85hp Johnson?

taylor786

Cadet
Joined
Sep 5, 2011
Messages
18
Will my 73 135hp lower unit fit on my 77 85hp Johnson?
Someone said it would and someone said it wouldn't.
I would like your guess!
Thank you!
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: Will my 73 135hp lower unit fit on my 77 85hp Johnson?

It should fit and shift okay. I don't know if the gear ratio is correct tho'. I'm sure I'll be corrected if I'm wrong.
 

jmanbaker1

Recruit
Joined
Jul 6, 2012
Messages
1
Re: Will my 73 135hp lower unit fit on my 77 85hp Johnson?

Will my 73 135hp lower unit fit on my 77 85hp Johnson?
Someone said it would and someone said it wouldn't.
I would like your guess!
Thank you!

ive tried that before, i tried installing the lower unit from a 1976 Johnson 135 onto a 1982 evinrude 115, and the reason it wont work is because the input shaft on the 135 foot is 7/8" diameter shaft size. the 115 has a 3/4" diameter input shaft. of course you cant take the shaft out of one foot and put in the other because the housings are different. they are two completely different pieces. i believe the 85hp motor would accept a 115hp foot, but not a 135hp foot. the best way to find out is to look up a water impeller for both motors and check the I.D. of each impeller.
 

McGR

Senior Chief Petty Officer
Joined
Jun 19, 2004
Messages
664
Re: Will my 73 135hp lower unit fit on my 77 85hp Johnson?

As jman discovered, a '76 wont fit a '82. This is because OMC redesigned the lower units in the late 70's. However, '73 was the first of the hydro-mechanical LUs. This design was used on the OMC V4s until about '78 or so. I believe the '73 should work on a '77. To be sure look at the parts breakdowns at evinrude.com.
 
Top