After the first year since obtaining and restoring a genesis 1000; Gotta say this has been a heck of a grill so far. One thing I have noticed though (and this has been ever since ive owned it) the front burner valve gets a bit stiff when the grill is heated up. The other two move smooth as silk with no noticeable difference in cool or hot grill. Anyone else experience this? can these valves be serviced? I pulled the orifices when I rebuilt the grill and cleaned them, but that was the extent of any tinkering with the manifold. just wondering.