Thank you for your comment. I was wondering also if the breather hose not being on could be a reason for a noticeable amount of black smoke from the exhaust.
Nope would make no difference to exhaust emmisions at all infact would make them better if your engine breaths oil as it would be going to atmosphere and not into the engine
If your engine has been breathing oil into your intake then id suggest taking a look at your air filter it may be clogged with oil and causing your black smoke