Date: Wed, 25 Jun 2008 11:58:19 -0700
Reply-To: Stuart MacMillan <macgroup@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stuart MacMillan <macgroup@COMCAST.NET>
Subject: Re: electrical testing proceedure question..Not van specific,
but..
In-Reply-To: <000501c8d6ef$8f443980$4001a8c0@gateway.2wire.net>
Content-Type: text/plain; charset="us-ascii"
Your alternator is shot, or completely disconnected. You may be able to
squeeze some more life out of the battery if you buy a good charger, fully
charge it (if it will take a charge), and maintain it with the charger.
Farm duty doesn't get it charged.
If you want to go a cheaper route, just get a new deep cycle battery and
charge it up every night. Since it isn't driven much, a good battery will
work without an alternator for what she uses the truck for. Even your bad
battery seems to be able to handle that.
Stuart
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Don Hanson
Sent: Wednesday, June 25, 2008 11:16 AM
To: vanagon@GERRY.VANAGON.COM
Subject: electrical testing proceedure question..Not van specific, but..
...It may help some listee who's maybe wanting to learn to test the output
of a van's alternator.
I'm trying to figure why my SO's old chev farm truck won't keep starting.
70s era 350 Chev that's been un-killable. She uses it carelessly around the
place to drag, haul horse sh*t, go to the dump, etc. It gets absolutely no
care..Lately, she's been jumping it to make it run..today, I get the
pleasant task of 'fixing it'..Love the Honey-do's...not..but..
So, the battery is 7 years old..Probably time for a new one, yes? After
cleaning all the ground points and the terminals and putting it on the
charger overnight, it shows 12.57 at the terminals when the truck is running
and the same when it is not running...
"Aha!" I think, "The alternator is shot, too" So I dismantle enough so I
can put my multimeter onto the alternator terminals, but I realize I know
not what to expect or haven't a clue as to how to diagnose the readings I
get. There are two smaller wires leading to a double spade plug in a rubber
boot. I get a low voltage reading across those like about .4 or somesuch..
There is one larger wire on a ring connector that is bolted on to a post on
the alternator. That one disappears under the headers, perhaps going to the
starter?..anyway, I read the same voltage, truck running, (12.57) off the
large post (output?) as I get off the battery terminals when I read directly
across the battery..I assume, and this is the question, that the large wire
is the output for the alternator and should read +13~ v..right? My van, I
get a reading across the battery of around 13.4 when the motor is on...12.7
or so when it's not running.
Did I do right? Should I get more than "ambient-- same as the battery"
voltage from that larger terminal on the alternator? Should I pull the
alternator and take it to my local autoparts, where they advertise "Free
Electrical testing"? And get another battery at the same time? Help...I am
an electrical dunce..
Thanks and sorry the question isn't Van-centric on a Wednesday, yet.
Don Hanson
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