Tractor is a 63 4000 gasser. I visit "Ol Blue" once every week or two. Last few times I tried to start her it would turn over but not start and gas would spray/seep out somewhere around the manifold area. It will eventually start and run kind of rough for a bit and then seems to run fine after that. There's no visible gas leak before starting and oil doesn't seem to have gas in it. On a possible related note(or not) after about 45 minutes it starts running rough, especially under load. Haven't tried troubleshooting that issue yet. On that subject(troubleshooting) I know there's been a lot of good info on here, much of it in bits and pieces. Does anyone know of a link to a good comprehensive step by step process for troubleshooting spark and fuel issues? Thanks for any help, Mark.