Mercury Tower of Power Lower Unit Help

[LNatale]

Good day. I am new to boat ownership. I have 1985 90 hp 6 cyl. Tower of power. I hot a rock, and broke most of the lower unit off. I need to find out if a lower unit from a 1976 Tower of power will fit my engine. Also , are these long or short shaft engines. Thanks on advance.

 

[Chris1956]

Most of the Mercs from that era are long shaft motors. Where are you located?

 

[LNatale]

I am located in Maine.

 

[Chris1956]

I would expect the '76 gearcase to fit your motor.

 

[jimmbo]

Welcome to iboats
When you said you knocked off most of the lower unit, did you mean most of the skeg, or the gearcase split open and the propshaft, bearing carrier, reverse gear, and other parts are on the lake bottom? If it is just the skeg broken off, a replacement can usually be welded on. I am 99.9% certain that by the mid 70s the inline 6s were only available in the 20" length. I am also certain that the splines on the engines remained the same