I have a johnson 100hp. It has two screws for changing the lower unit lube, one on top and one on bottom.
I was taught to fill it from the bottom screw until it starts to leak out the top screw hole. The oil i use is in a standard type oil container and not in a tube so its impossible to squeeze it out. I think they make a special hose with threads for filling this but im not sure.

How do you change yours? from the top or bottom? Any special tools to make this easier? How often do you change yours out?

Go to Wally World or other and get a pump for putting the lower unit oil in. You can pour your oil into a clean quart bottle.

Have to fill from the bottom to avoid air pockets & underfilling.

annually. before the 1st freeze, so if any water has got in, it won't bust open your gearcase.

OK thanks, i thought they had a pump or something to make it easier. Its impossible the way i was trying to fill it the other day.

when you reemove the screws,be sure you dont loose the rubber O rings on both screws.......got to have the pump.

I have a 200 hp Johnson and just recently change mine out. I used the synthetic type with the pump filling it from the bottom. However, I didnt see any orings on the plugs when I pulled them out. So far no leaks though

My Merc has pplastice washers. I have to careful not to loose them. They are damn near impossible to find unless dropped on a white cloth.

If you'll drain some of your oil, you'll see what it looks like with water. actually they've been using nylon washers stead of rubber o-rings for awhile now, they usually stick to the screw, you might've just not noticed.

I've reused mine several times with no problems but they will wear out eventually. Some people replace 'em every time, not a bad idea.

Wait until you have to buy the screws themselves. $12 a piece.

I never knew there was washers or o-rings, guess i better check that out. They may be on there but i havent noticed them.
Thanks for the info. .

There is a little pump you can get. Screws right into the bottom hole. I bought mine years ago from an OMC dealer. BTW, I change my lower unit oil twice a year. It's a 1980 V4 Evinrude and still purrs like a kitten. Take care of them, and they'll last a long time. Dont....and they'll crater on you in the middle of the season.

Like everyone has said above. It's a piece of cake with the pump. I am sure it has been said before, but don't use the cheap oil. Make sure you use some good oil because it will save you alot of problems in the long run.

whats the best oil in your opinions?

I used the lubrimatic synthetic. I dont think you can go wrong using sythetic at $10 bucks a quart

I use wallyworld super-tech. What ever you do, use a marine lubricant. Automotive gear oils lubricate just as well no doubt, but they can lose their viscosity in the presence of water; marine lubes have (should have) additives to counteract that tendency. So if you take on a little bit of water it's less likely to cause any damage before your next oil change.