replace lower unit vs. whole drive?

[mazman]

I hit a rock or something and broke my drive shaft ( the top groved piece sheared right off) it also bent the prop shaft and broke off part of my skeg. The shop wants 1400 + to repair and luckily I had already found your web site and told him not to fix it. Thinking about replacing just the lower unit and the mechanic said that I would need to replace the seals that were damaged from the broken shaft if I replace the lower unit myself. I have a 1987 ALpha one with a 120hp merc. that has had very little use over the years and I am trying to decide if I can get away with just replacing the lower unit.

How difficult is it to replace the seal in the upper unit? Does this involve taking the upper unit apart? And what else may be damaged in the upper unit ? thanks.

[Technical Support]

Usually when you hit something the upper gears will take a good hit also, but appear ok. Then a month or two down the road the upper will fail on you. I would recommend changing the whole drive.

If you decide to just replace the lower, changing the seal in the upper is no problem. Justi seperate the lower from the upper, and then flip the upper upside down. Pop the old seal out with a screwdriver and install the new one using a suitable mandrel.

Tech Support