i have a 1985 bayliner 4cyl volvo engine with volvo penta i/o. Can anyone please tell me how does a heat exchanger work? Like give me a website, or an article about heat exchangers. When i turn on the ignition for a while it over heats, but its not on the water its in front of my house. Is this why it overheats? Im wondering its overheating because it is not running in the water? thats why i want to learn more about heat exchangers? My dad is a mechanic, and he wants to know how the cooling system works, so he can fix it. Any websites or articles would definity help. thx