1990 Ford Falcon wont start

Hello, I have 1990 ford ea wag, drives great starts good first time every time in morning, say I drive for 1 hr turn car off, go in shop, then try to start car wont start, only sometimes, (alt) working very good, battery chargers up to 14.46 volts when driven, about 13 volts at idle, parked over night its 12.70 volts, stater motor seem good, have new spark plugs & leads, distributor-cap, also when car under load ( up hills), car over heats only up steep hills, will idle all day & not over heat, water pump OK, thermo OK, no leaks, no water in oil, idle ok, changed radiator with good 2nd hand one still the same