Having left my Haynes manual at work, I proceeded into additional
diagnostics with... trepidation. (I'll have it tomorrow, though)
Here's the latest:
Voltmeter to gauge common ground, + to big brown wire on stock alternator
Ammeter inline on + circuit for ALL current from battery (using 4 gauge new
cables)
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)
If I start the car, voltage "flutters" from 8v up to battery max. Max drops
as the battery discharges. It takes about 2-3 hours of driving (no lights)
for the battery to discharge.
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)
This WOULD explain why I couldn't get a relatively new radio to work in the
car...
Again, the alternator was tested (at Pep Boys) and puts out 15v for
charging. They said that it's good.
I was able to isolate the problem further, though.
I started pulling fuses (no change) and pulling various leads to see what
behaviour the result would be.
When I pull the battery - cable, the car cuts off. The alternator is not
putting out enough juice to run the car (but according to the test, it IS
capable of doing just that)
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.
***My best hypothesis is that the trouble is related to one of the smaller
brown alternator wires. My ignition light does light while or just after
starting the car, and stays on until the voltmeter begins its "flicker"
cycle.
Why would I be getting these symptoms? HELP!!!!!
I did have some ground issues. Cleaning them up helped to make the problem
"repeatable": far better for testing.
Ammeter NEVER shows the vehicle charging. (except when I put my battery
charger on at the end. That did show +6A for my 6A charger.
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: DANMAS@aol.com [mailto:DANMAS@aol.com]
Sent: Wednesday, May 19, 1999 6:43 PM
To: gsmith@cvn.net
Subject: Re: Strange charging issue... but I may already be a winner.
In a message dated 5/18/99 4:38:07 AM Eastern Daylight Time, gsmith@cvn.net
writes:
> I used the
> Temp gauge's old ground, and set about figuring where to hook up the
> positive.
>
> With the key off, I get
> 13v at the battery
> 13v at the alternator center (big brown) wire
> 0v at the other alternator connections.
> This makes sense, because I traced the (big brown) wire to the starter
> relay, where it's tied to the battery + lead.
>
> With the car running, it gets weird. I get <8 to 12v in a flutter,
probably
> averaging 7-10v It rarely hits 12v at all. The ammeter shows a constant,
but
> small draw, until the lights are turned on.
Gregory,
Did you connect the voltmeter positive lead to one of the light green wires
connecting to the other meters? If so, that could account for your voltage
fluctuations. The other meters are fairly slow to respond, but if your
voltmeter is quick acting, you could be seeing the fluctuating output of the
voltage stabilizer. Try connecting the voltmeter to any of the solid green
wires. Measure the voltage at the battery with the engine running at a high
idle -- 1500 rpm or more. You should see a rock steady 14-15 volts.
> Does the 1980 Spitfire use a ballast resistor? I have the "warranty
> replacement" electronic ignition, apparently this was a factory recall.
>From the factory, yes. It's item #8 on your wiring diagram, and is a piece
of
resistance wire bound up in the harness (on later models -- on earlier
models, it was a discrete ceramic "thingy" -- attached to the firewall, I
believe). On a TR6, this wire is pink and white, and looks sorta like a
shoelace. I imagine it is the same on the Spitfire.
> I have an unidentifiable coil (came with the car), but have a Lucas 40Kv
> Sport coil available. What would it take to install the Sport coil? Is
there
> any wiring change I need to do?
Check: http://www.vtr.org/maintain/ballast.html
for details on removing the ballast.
> Last of all, I would appreciate a prompt reply: I'm going 3 1/2 hours to
the
> Richmond Triumph Register (VA) show this weekend. Weather permitting, I
want
> to bring the Spitfire!
Sorry it took me so long to get back to you. If you run into problems, let
me
know, and we'll work it out.
Dan Masters,
Alcoa, TN
'71 TR6---------3000mile/year driver, fully restored
'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
http://members.aol.com/danmas/
'74 MGBGT---3000mile/year driver, original condition - slated for a V8 soon
'68 MGBGT---organ donor for the '74
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