'89 Generator light
April 2010 TOTM Winner
Joined: Jan 2010
Posts: 515
Likes: 3
From: Panama City, FL
The 10 volts... is that with the engine running?
After cleaning the battery posts & cables,
if you still have less than 12 volts on your volt meter with the engine idling,
replace your Alternator.
The alternator should produce 13-14 volts with engine idling.
If you have a really old battery and perhaps two of the cells were bad,
well that could be what burnt-up your alternator to start with;
trying to keep the bad-cell battery charged to 12 volts.
An Alternator only produces a trickle amount of electricity and is not designed to charge a battery continuously, an alternator is only for keeping 12 volts in a good battery.
If your new alternator comes with a NEW Wire Plug-in, use it.
Cut and splice it onto your alternator wiring harness.
There may be a heat-related issue with the old alternator wiring plug-in,
because it gets really hot and if not replaced with the new alternator,
the new alternator may fail after a short time and will have to be replaced again.
Check your alternator wire plug to see if it has gotten hot and slightly melted,
you can buy the wire plug separately, if it does not come with the new alternator.
Try to purchase a Life-time warranty alternator,
they usually have this wire plug included.
|
After cleaning the battery posts & cables,
if you still have less than 12 volts on your volt meter with the engine idling,
replace your Alternator.
The alternator should produce 13-14 volts with engine idling.
If you have a really old battery and perhaps two of the cells were bad,
well that could be what burnt-up your alternator to start with;
trying to keep the bad-cell battery charged to 12 volts.
An Alternator only produces a trickle amount of electricity and is not designed to charge a battery continuously, an alternator is only for keeping 12 volts in a good battery.
If your new alternator comes with a NEW Wire Plug-in, use it.
Cut and splice it onto your alternator wiring harness.
There may be a heat-related issue with the old alternator wiring plug-in,
because it gets really hot and if not replaced with the new alternator,
the new alternator may fail after a short time and will have to be replaced again.
Check your alternator wire plug to see if it has gotten hot and slightly melted,
you can buy the wire plug separately, if it does not come with the new alternator.
Try to purchase a Life-time warranty alternator,
they usually have this wire plug included.
|
Last edited by 1987 F-150 XLT 4x4; Nov 13, 2010 at 07:03 AM.
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 2
Likes: 0
From: Zebulon, GA
Wow!
I had an Auto Zone Alternator on there, so I took it off and took it in. It tested good but they gave me another re-built one anyway since it had been 8 years. I installed it and the volts are 12 and the light is out. However, When hooking the battery back up, I noticed a cracked battery terminal connector (not the post from battery). So, based on you guys' info, I will replace the battery connector (?) and have the battery tested to ensure all the cells are working.
Why did the old alternator pass the test? Go figure.
Thanks, so much for all your help! Best advice yet!
Why did the old alternator pass the test? Go figure.
Thanks, so much for all your help! Best advice yet!