This is my second post on this forum and I just wanted to say this forum is awesome and the people on here are great. Any way's I have a 1977 lund 20' aluminum open bow with a omc i/o 302. I have been doing as much research as I possibly can. What I have found out is that the drive I have is not the most wanted system but its what's there and I am sticking with it. I would like to go over the entire system and replace any parts that are needed or could give me problems. The engine I am framillar with being a 302 but the rest is all new to me along with how the cooling system works on this. I started with the basics of replacing the gear oil and found water in both the top and bottom units. I found that I need to presurize them and check for leaks and would like to know what to look for exactly and would it be better to "bench test" them. Also there is some wear on both ball drives and wonder how much it too much? I was thinking of ordering a whole seal kit for the top and bottom. Is this a good idea and if so any reccomendations? Also what is normal wear for a prop.