I have a slow leak near my fuel return manifold on a 2006 Troll. The previous owner thinks it's coming from the manifold, not one of the fittings near the manifold. I think he's correct. The bottom of the manifold has a bolt which is sometimes moist with diesel. I attached a picture of the manifold. Has anyone else had issues with this. What am I going to find if i take this apart? Anything serviceable?