Hi I recently had a 1964 327 small block chevy engine rebuilt. After the rebuild it started to smoke from the right side exhaust tail pipe and some from the left side but not as bad. I remove the intake manifold to check for a slipped runner gasket allthough the motor ran well with good vacumn. As I looked into the head intake runners there was a lot of oil. I suspect the valve guide seals are leaking around the outer part as the are nylon and I don't think they are sealing to the new bronze valve guide They are brand i've never heard of "Corteco" It seems the clamp on these seals doesn't make a perfect circle on the larger side. There seems to be some machining marks on the guides also. I think if these seals were made of rubber I would not have had a problem. What do you think? Thevetteworks@msn. Com
Everything you said makes sense. What are the guides made from? Also, where were they made? I have to say one thing about valve guide seals, usually you will get the most smoke from them after the engine sits for a few hours. Also, you will most likely see the most smoke from them when under heavy acceleration. Is that what you are experiencing? Also, the brand you mentioned, I never heard of. They need to fit tight on the valve guide. Otherwise, they will leak. As far as the machining marks, that is normal if they were redone, but were they properly checked to make sure they are within specifications?