Battery or Alternator?

[snowman74]

Howdy once again to all my favorite Bronco freaks,

Okay, I think I know the answer to this one, but...

Difficulty (especially when cold) in starting engine. When in nuetral and idling, with heater on, power output on voltmeter goes way down (6-8 volts). Then when I turn off heater, power output goes right back up to normal (12-14 volts). I'm thinking it's the alternator, but how can I tell for sure? I know I can go have alternator tested...but are there any tests I can do myself?

Also, a few weeks ago, when it was REALLY freekin' cold here, the starter gear got hung up on the flywheel. I could not turn the power off. Even when I turned off ignition, flywheel was still turning...and the engine would crank right up when I turned the ignition back to on. I think this is because it was just so cold out, but does anybody think the starter might be bad also? It's cranked over just fine every time since then...except for the last few times when I noticed the voltage problem.

Help is always much appreciated. >-

 

[mbtech2003]

i'm having a simmilar problem with mine. i think it's just a bad engine ground. i've been too lazy to clean the connections. it's not the altnator because i just put a 170amp alt in my truck and it still does the same thing. at night when u start the truck is their a spark from the starter to the frame??? that is what mine is doing so that is y i think it is a bad ground.

 

[snowman74]

I'm not noticing any spark from the starter to the frame. I've even checked the battery terminals to make sure wire on are tight. Tight as they can be. Still scratching my head. It's got to be the alternator, I think. Why else would the voltage go down under normal load? Battery seems okay.

 

[92pobronco]

I'm not noticing any spark from the starter to the frame. I've even checked the battery terminals to make sure wire on are tight. Tight as they can be. Still scratching my head. It's got to be the alternator, I think. Why else would the voltage go down under normal load? Battery seems okay.

 

[92pobronco]

i think its probably your battery not gettin a good chrge cuz of the cold mine did it 2 so i threw a new battery in andshe was perfect. I got the high pwr altinator too. age and cold are batterys enemys

 

[Seabronc]

Check your battery to engine block (-) connection ( take it off and clean the connection then reattach it). If that is OK, you may have a bad voltage regulator. Once the engine is running, the battery should be out of the picture. If the alternator is working correctly, you should be able to disconnect the battery once the engine is running. Just be careful not to short the battery (+) lead to ground.

Good luck,

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