Welcome to the site. Not it is not a common problem, and yes you either need to retorque your head bolts, or if that does not work, a head gasket, and to check flatness of both head and block while things are open. Don't forget there is one head bolt under the carb. If this is just going to be a hunting rig, you could try some of the auto parts store remedies before doing a pull down. Good luck.