On my 1972 XJ-6 (4.2 liter engine) I am having a problem with the engine smoking. There is a carbon canister to which is attached a tube from the gas tanks, a tube (or hose) running to the engine breather on the front of the engine above the water pump, and a tube (or hose) that is open to the atmosphere. There is also a hose connection that goes from the breather to both carbs. I am getting a bit of smoke exhausting from the hose that is open to the atmosphere and I also get smoke at the hose connecting to the carbs when I disconnect it from the carbs. When I remove the oil filler cap from the left cam cover there is a bit of smoke present even right after starting a cold engine. Has anyone ever experienced this problem and, if so, what is the "fix"?