Re: johnson 150 lower unit exhaust leaking lower unit oil
First you'll want to confirm that what you are seeing leak out is indeed lower unit oil.Unburned two cycle oil commonly weaps out the prop hub on some outboards and is generally black or very dark in color.Gear oil will have a bilgy and rather unique odor and unless in dire need of replacing will be generally a more carmel color.If your case is a leaking propshaft seal or bearing carrier "o" rings it is likely that water has intruded into the gearcase.You can determine this by simply draining the lower unit oil and inspecting the lube.If water is present it will appear milky or darkened and emulsified.
Anyhoo ...if it turns out that the hub is in fact weaping lower unit oil the likely parts you'll need to fix it will be propshaft seals and/or bearing carrier "o" rings.
