MG Car Repair: MGB Exhaust smoke., worn bores, mgb roadster

Question
Hi. I have a 1973 MGB roadster. I have just fitted a new unleaded head, including all gaskets. Since i have done this i am getting smoke from the exhaust under acceleration. The carbs settings are way and and are running rich, could this be the reason for the smoke, as the new oil has a petrol smell to it.

Answer
Hi Aidan
The short answer to your question is yes.  A rich engine will smoke, usually blue smoke rather than black.

Set the carbs and see if it goes away.  If the smoke persists, then you probably have worn valve guides or worn bores.  My next test would be to check the compressions.

I note that you have used the feedback system to ask another question.  

Since the carbs are set up correctly and the compressions are all 140, it is beginning to look like the new head is faulty.  However, it could also be worn oil control rings.  If they are OK then it could be faulty valve guide seals or excess play in the valve guides.  Did the engine smoke before you replaced the head?  Are the rubber breather pipes to the tappett side cover all clear?  You need to be sure of your facts before complaining about the head.