My Christmas Train is one year old.  I set it up for Christmas.  I lubed it and it runs great.  Last night, I used left over smoke oil.  It worked great.  I ran out then I used new smoke oil which I just received from your web site.  No smoke.  Due to an earlier question today, it was suggested that the smoke generator might be burned out.  I tried to take the upper body off the engine to check.  I could not figure out how to do that.  I could not find instructions or a drawing for the 4-6-0 engine on your web site.  What do you think is the problem?  Is it the new smoke oil?  Is it a burned out smoke generator?  If so, how do I remove and install a new one?