i have 2 mercury 90hp towers 1 is 78 one is 84

[Jolly Martin]

will the lower unit from the 78 fit on the 84

 

[racerone]

I think it will.

 

[Jolly Martin]

thanks

 

[Texasmark]

What do you have to loose if it doesn't.....a little time?

 

[jimmbo]

It will fit. The 78 likely is a Older Style, with a less streamlined shape.

My 78 90 had the post 78 gearcase on it.