I have a 1998 Lincoln Navigator and I just had that radiator changed. We couldn't get one of the bottom hoses off so we had to go to the store to get liquid wrench and he didn't tighten up one of the hoses all the way and oil or something leaked everywhere. When he was done he told me to start it. It started and it seemed good until he tightened the antifreeze cap and my heater started losing heat instantly. I know there could still be some air in the lines but it's been almost a week now and the motor sounds like it's dying now and now my heater sounds like it's dying and will barley even turn on. Could he have got some oil or something in the radiator or something. I really don't know too much about cars so I'm just looking for some possible answers. Thanks in advance!!