help car over heating

Ok I have a honda accord 1996, v-6, with 155k miles, it has started over heating, I have replaced spark plugs, both fans are working, checked all hoses, replaced the termostat, flushed the raditator, added coolant, it will drive good for about 3 days and then start's overheating.. Any idea's on what could be the problem???

Thanks

Seems like you did everything right to me. Is your radiator cracked? Does the coolant leak? If anything try replacing the radiator.