Which year lower units are compatible with '84 75hp?

[sutor623]

Hey guys, had a close call last week. Was cruising around at 4-5MPH and noticed some below surface rocks, and smacked one with my skeg. Didnt do any noticeable damage, but I got to thinking, if that had been worse I'd have been off the water for weeks in search of a new gearcase. So I was just wondering fitment compatibility of gearcases as well as gear ratio compatibility. Just want a spare hanging around. E75tlcrd '84 75horse Thanks!

 

[Chinewalker]

Re: Which year lower units are compatible with '84 75hp?

About 1978 to 1988 three cylinder units, 60 to 75 hp. Four splines on top of driveshaft.

 

[sutor623]

Re: Which year lower units are compatible with '84 75hp?

About 1978 to 1988 three cylinder units, 60 to 75 hp. Four splines on top of driveshaft.

Thanks brother! Wealth of information, you are.

 

[sutor623]

Re: Which year lower units are compatible with '84 75hp?

One other thing, if you know this. Are the gear ratios the same for the 60, 65, 70 and 75? I think Im dreamin here. Also, this is a '77 model, but it looks like it would fit just fine, what do you think? Is this why you said "about" 1978? http://www.ebay.com/itm/Johnson-Evinrude-lower-unit-Off-a-1977-65hp-outboard-/121133159668?pt=Boat_Parts_Accessories_Gear&hash=item1c341954f4&vxp=mtr

Edit- So I just figured out what the big difference is from the pre-78's to the 78's are. They shift backwards. The older models push down for forward and the newer ones pull up. Seems confusing.....

 

[sutor623]

Re: Which year lower units are compatible with '84 75hp?

Chine, I found a decent 1989 70hp Lower unit with prop for $90 on CL. You said the L/U that I could use was '78-'88. What changes should I look for in the '89's? Also a bummer as this L/U does not have the shift shaft or shift shaft housing with it....

1989 Evinrude 70HP Lower Unit & Prop #E70ELCEM

I think the difference is the driveshaft splines. I cant really tell by the pictures, but it looks like there are way more than 4 splines on the driveshaft.

 

[Chinewalker]

Re: Which year lower units are compatible with '84 75hp?

You hit the nail on the head. Actually, if you have your '84's driveshaft, you can have a shop swap that into the '89 and it should work.

 

[sutor623]

Re: Which year lower units are compatible with '84 75hp?

Cool thanks boss! I also noticed that the pre '78 motors shifted in Opposite of mine. Luckily my current gear case is in excellent running condition so no frankensteining for me! I jus want to find a decent just in caser that doesn't cost $700. I don't even mind it having some issues. Anyway thanks for the pointer I will surely know what to look for now!