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Re: Starting Woes - Now Mysterious!

To: "Jason B Lonon" <j_lonon@lycos.com>, <mgs@autox.team.net>
Subject: Re: Starting Woes - Now Mysterious!
From: paul.hunt1@virgin.net
Date: Mon, 14 Aug 2000 19:38:15 +0100
Cast aluminium certainly conducts, but would it have the strength to put up
with all that cranking force?  It certainly doesn't need the lightness.  Is
it magentic?

Does your starter rotate at all?  If you try to crank a seized starter (or
engine) you will take a helluva lot more current than if the engine turns,
and more current means lower voltage.

Not sure exactly what voltages you got where, and which wires you touched to
what.  The white with brown stripe supplies power from the ignition relay to
the ignition load.  The wire that operates the starter solenoid seems to be
a brown with a white stripe, i.e. it changed colour from white/brown to
brown/white when the ignition relay appeared on the scene.  That's what
Haynes says, anyway.

What is the voltage at the battery posts (not the connectors) when you try
to crank?  Under normal cranking it should be about 10v.  If it goes down to
2-3v then the battery is not up to doing what it is being asked to do i.e.
either the starter is trying to draw much more current than it should
(starter/engine problem), or the battery cannot supply a normal cranking
load (battery problem).  Smoking at the battery indicates a connector
problem or possibly it is just boiling under excess current.  You say the
terminals are shiny but what about the connectors?  Do you have the
clamp-type that bolt up or the cup type with a screw that goes into the
post?  The cup type are a pain because they expand over time, people stuff
them with silver paper which works for a while, but then becomes an
insulator.

If the voltage at the battery posts stays at 12v move up to the connectors,
then the starter body and heavy current terminal on the solenoid.  If any of
these drop to your 2-3v then you have a bad connection between there and the
last place you measured 12v.

If all those are all 12v you aren't even trying to crank.  Check the voltage
at the brown on the fuse block, white/red on the ignition switch and starter
relay, white/brown on starter relay and solenoid.  All those should be at
10v during cranking.  If they are 12v then the solenoid, or the white/brown
connection to it would appear to bad.  If any of those drop to your 2-3v
then the fault is between there and the last place you measured 12v.  If the
brown drops to 12v then you need to check back towards where the browns
connect to the solenoid, including a big brown double through-connector if
you have one.

I have more 'Won't Start' faulting tips on the web site below, select
'Spanners', 'El;ectrics' and 'Won't Start', funnily enough.

PaulH
http://www.mgb-stuff.org.uk



----- Original Message -----
From: Jason B Lonon <j_lonon@lycos.com>
To: <mgs@autox.team.net>
Sent: Sunday, August 13, 2000 11:52 PM
Subject: Starting Woes - Now Mysterious!


>
> Well, I've had the day to poke around, and things are even stranger than I
had imagined.
>
> Several people emailed saying it sounded like a bad ground or bad battery
connections, but I don't think that's the case, because I've cleaned the
terminals to shiny and tightened them nicely. Also, what I'm about to relate
kind of rules this out.
>
> I measured the voltage across the starter terminals - 12 volts. I measured
the voltage across the ignition terminal and ground when the key is turned -
I got 0v. Ok, that tells me why the starter isn't running. So, I go the
starter relay. With the key in the on position, I touch the brown 12v line
to the white/brown stripe ignition line (which should cause 12v to go to the
starter motor), and then the voltage across the ignition terminal is only
2-3 volts (not the 12v it should be). So, at this point I'm thinking "there
must be something going on here that's a little beyond just a bad part."
>
>
> That's about when my wife walks out and says, "oh, you've got the lights
on." I was immediately interested in this because the key was not in the
ignition switch! Sure enough, the only way to turn off the parking lights is
to disconnect the batteries. When I reconnect them, the lights come on! And
I do not have anything jumpered or altered from the original circuit.
>
> I don't know if anyone can offer advice on this, it does sound like a
specialized problem, but I just thought I would share it because it seems a
little bizarre.
>
> My next step is to look at a wiring diagram, I guess there is a short
somewhere involving the parking lights.
>
> Thanks for listening!
> ---
>
> Jason B. Lonon
>
>
>
> Send your favorite photo with any online greeting!
> http://www.whowhere.lycos.com/redirects/americangreetings.rdct
>


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