spitfires
[Top] [All Lists]

RE: Strange charging issue... FINAL Analysis

To: "Atwell Haines" <carbuff@nac.net>, "John T. Blair" <jblair@exis.net>,
Subject: RE: Strange charging issue... FINAL Analysis
From: "Gregory W. Smith" <gsmith@cvn.net>
Date: Mon, 24 May 1999 02:02:49 -0400
Per recommendations, I checked alternator voltage at all 3 connections while
wire disconnected, and car running off battery. None were high enough
(forget actual readings)

Is there a required connection for the alternator to begin producing
current?

Replaced alternator with a 1980 TR7 AC type alternator; fiddled with the
Spit spacers to make it fit. Voltmeter shows 14-15v alt to battery, dash
voltmeter shows flutter from 8v-15v. Ammeter shows +15-+30A instead of -2
to -5 or so. I'M CHARGING!!!!!

Per another recommendation about the dash gauge voltage regulator, hooked
dash voltmeter to chassis ground. Now reads ~15v constant.

I'd say everything electrical's copacetic for the next... half hour or so.
At the witching hour, the demons of Lucas are loosed! ...or is that only on
Halloween?


On another note, Triple-C had a neat baseball cap for sale at the Richmond
Va show that read something like "LUCAS Quality Control Inspector" I think
it was $12. Embroidered, canvas, nice hat.


Gregory W. Smith      http://www.cvn.net/~gsmith
Member, Central Pennsylvania Triumph Club
1980 Spitfire 1500 "for the wife" :)
1980 TR7 Spider v8 (in progress)
1980 TR7 30th Anniversary Edition (deceased)

-----Original Message-----
From: owner-spitfires@autox.team.net
[mailto:owner-spitfires@autox.team.net]On Behalf Of Atwell Haines
Sent: Thursday, May 20, 1999 8:01 AM
To: John T. Blair; spitfires@autox.team.net
Subject: RE: Strange charging issue... STILL Not Fixed!



At 01:43 AM 5/20/99 -0400, John T. Blair wrote:
>
>At 11:32 PM 5/19/99 -0400, Gregory W. Smith wrote:
>>Here's the latest:
>>
>>If the car is off, I get 12-13v on the voltmeter. The big brown alternator
>>wire is ALWAYS hot (it shares the same post on the starter relay with the
>>battery + cable) This tells me battery voltage is 12-13v... OK
>>
>>If I turn the car on, but don't start it, voltage drops below 8 (scale is
8
>>to 16v)

Does disconnecting the square (main) plug to the alternator during the key
on - engine off test change the voltage measurement?   If so it's gotta be
the alternator.  If not I'll agree with John...you have a short (or maybe a
broken wire) and I would suspect the harness going from the alternator to
the car (that has the most vibration).   BTW are the valences still on your
car? The left one supports that wire harness...

>>If I hook up the voltmeter directly to the battery (+ and -) I get the
>>expected ~12v
>>So I'm showing the alternator-supplied current (I think)

Nope, if you had alternator current you should get at least 13.5 V there.

>>Again, the alternator was tested (at Pep Boys) and puts out 15v for
>>charging. They said that it's good.

Yeah, but why won't it put out 15V when installed in the car?  I would
check the voltage right at the backside of the alternator plug.  (BTW look
carefully at the plug sockets & ascertain that all are snug)

Here's a thought:  the stock Lucas alternator had a wire retaining clip on
it to hold that plug tight.  When I had mine rebuilt, they left it off (I
did retrieve it from them later).

>>When I pulled off one of the LT - coil wires, the car also cut off. But my
>>"flickering" gauge persisted. -8 to about 10v 4-5 times a second. It would
>>stop if I disconnected the Molex(?) 9 pin plug to the steering column.

Coil voltage goes thru there.

Keep trying,

Atwell Haines




<Prev in Thread] Current Thread [Next in Thread>