Hi, My heater core is clogged, and I'm going to replace it. I am curious though, if the core is clogged then is the rest of the cooling system full of crud too? Should I replace the radiator, or flush the system before putting in a new heater core? Israel

1986 Chevette -went to start the other day; was not 'catching'- starter kept turning over but car was still not starting, eventually wore down the battery somewhat and had to pushstart the car. took a couple pushstarts to finally get it going, large cloud of black smoke out the tail pipe upon starting. i figure that i managed to wash out the cylinders at the same time, causing the smoke. -later that day, starter turned over three or four times and then suddenly stopped. no noise from starter upon attempting ignition. not turning over at all. i am thinking the starter, but could it possibly be the alternator? how can I tell? thanks in advance.