New person

[spinnerg]

I own a 2005 ford explorer sport trac with 75,000 miles. It runs great. The battery is the type with the green/red eye maintenance free type. Recently the eye turned to red indicating the battery is not charging which stands to reason since it the original battery, a motorcraft battery and is over 5 years old. I meant to get it replaced but had to go on the road and drive it with the lights on and it drained the battery and left me stranded, the battery light symbol was on the entire time and I knew it was going to drain it. At any rate I replaced the battery and away I went, but still thinking it may be the alternator. With the new battery in and idling, the battery light is off (on dash) when I rev it up the light comes on at about 1500-1700 on the Tac. Last night as the truck was idling I removed the positive off the battery, it kept running, soon as I stepped on the gas it killed the engine, again at about 1700. I have also driven it with the headlights on the highway and the charging gauge with start to go down soon and as you drop below about that 1700 mark it begins to charge. My question is; is this a bad alternator and it was just a fluke that it is going bad about the same time as the battery? Will replacing the alternator solve my problem?

Thank you

 

[ragajungle]

If you aren't entirely sure you could bring the alternator into Advanced Auto or O'Reilly to have them bench test it. but with the way things are going with after market parts right now it might even be worth testing the new battery too. I have seen brand new batteries DOA.

I got a "new" battery from tractor supply company - charged it and it still was only getting 11.30 V fully charged on my test leads- there was a dead cell.

 

[spinnerg]

Thank you for the input rajajungle!! I just went and had it tested while on the truck, they said its the regulator in the alternator, which means I had to buy a new alternator...... oh BTW I did have them test the new battery and it was fine.

 

[BrooklynBay]

Welcome to this forum! A simple voltmeter test will show what the voltage is when it's idling.