Mechanics, help please!

I tried to start my van this morning, after it had sat unused for 40 hours, and it would only turn over very slow.It did just barely start. I ran it for about 15 minutes, hoping to charge what I thought was a dead battery,then turned it off and tried to start it again. The same thing happened and I was just able to get it to start.

I cleaned the battery posts, hoping it was dirty terminals and reconnected it. Know it turns over slightly but not enough to start

If I let it sit for awhile it turns over a little better.

This problem came out of the blue. I haven’t had any problem starting it at all in the past this was the first time.

Does this sound like a bad battery,a bad alternator, a bad starter or other?
Thank You for your help

Brad Amundsen

It sounds like either the battery or the alternator. Normally, 15 minutes would charge up a good battery enough for a good start, if the alternator’s putting out and the battery’s charging. The only way to know for sure is a voltage check. If you don’t have a meter, a lot of the parts store’s will check it out for you, then sell you what you need to fix it.