[WFBowen]

Is your generator light going off when the engine starts? First check your cables are clean and tight, the long positive one to the starter, the ground where it connects to the body in front. Then check your generator and voltage regulator.
Are you absolutely certain your battery is holding a charge? Buy a cheap multimeter (HbrFrt) and see what kind of voltage you have at the battery with the engine running. A good move would be the installation of a starter relay -easy and cheap to do.
Bill