Alright, I'll start by laying out the setting. It was about a week ago, I live in the Pacific Northwest (WA), it was pretty cold, but nothing serious (about 38 degrees outside). The car started up fine, everything was running, headlights were on, fan was on. About 5 minutes after starting, it literally stopped dead. No sputtering, nothing like that. The headlights stayed on.

The car had some trouble with oil leaking inside the car (over the alternator and other parts), so I had replaced the valve cover gasket about 9 months ago. As far as I knew, that solved the problem, but when I checked under the hood again when it quit, it looked like there was fresh oil on some of the parts, but I'm not certain.

I called into the local auto parts store, we had concluded that the oil leaking over the alternator would probably kill the power, so I replaced the alternator. After I switched it, nothing. The car will try to start, but it won't turn over and fire up. It was the same when the engine cut out before, I tried turning the key, it would try to start, but wouldn't turn over and fire up.

Before I start replacing parts that don't need to be fixed, figured I'd ask around and get peoples' opinions on what I should replace first. In my mind, it's either the starter solenoid, or the engine block itself has seized up. And yes, the alternator is hooked up correctly. It was one of the first things I checked after putting it in.

So, there you have it. Any input would be nice, any questions feel free to ask and I'll try to answer.

Thanks!