Running Hot

I agree that something sounds strange. Why do you say it runs hot? Has it boiled over? Are you judging "hot" just by what the temperature gage indicates? If so, try a thermometer in the coolant after you stop.

I don't see how it can be hot and not build pressure in the hose unless you have a really big leak, and then you should see a lot of water or steam. Usually, with a pinhole leak, like in a heater hose, after you lose enough coolant the rest gets real hot and the cap blows.