OK. I have had this problem before. It wouldn't turn over about 10% of the time. Wait 10 or 15 minutes and it would start. Hot or cold wasn't an issue, it would sometimes fail first thing in the morning or after warmed up. The problem was solved by filling the battery cells with distilled water (to the proper level), and charging the battery overnight. It has never failed to turn over since (6 months). The battery was not dead, it was just a little weak and there must be excessive resistance somewhere between the battery and the starter that cause the no start. Also, may be a sign that the starter has some resistance and needs a fully charged battery to do the job. Good luck.