The "ER" within the model number indicates the engine is a 1994 90hp JOhnson, not a 1995.
Retiring in 1991, I'm unsure of the cylinder design but I would assume it is a 90 degree model. Someone else will verify that one way or the other shortly I'm sure.
Pertaining to the carburetors, replace the broken housings and clean/rebuild the carburetors as needed.
The black oil is normally caused by excess fuel draining down thru the soot coated inner long exhaust housing. This should cease to exist when you have the engine running properly. However, check the gearlube coloring and compare it with what you see.
I just bought a 24' barge with 90hp johnson V4, model number is J90MLERC. Is this the 90 degree or 60, it looks like the diagram of the 90 as the cylinders appear to have a 90 degree angle. Does this engine have a good reputation? It is leaking from both carbuerators, someone has overtightened the drain plugs and the housings are cracked. Also there is black oil coming dripping from the prop area, what causes this? Any information I could get on this engine is appreciated. Thanks in advance.