Peter,
It sounds as though you have a healthy alternator. The TR250 unit puts
out JUST enough to power all your accessories.
A battery with an internal short will suck all the power from your
alternator and yes, the car will die.
FWIW, my past experience with the 250 has also led me to advocate
keeping your fusebox in A-1 condition. BTW, corrosion can form behind
the terminals, so just cleaning or beadblasting may not cure a problem
here.
Jim
----- Original Message -----
From: "Peter Macholdt" <vze2846b@verizon.net>
To: "6pack list" <6pack@autox.team.net>
Sent: Sunday, August 05, 2001 6:58 PM
Subject: Charging system on TR250
> Yesterday evening, I was driving home from a day-trip to the shore and
> pulled over to lower the top. When I tried to restart the car, all I
> could get was a half-hearted growl. The motor wouldn't even turn.
> I got a jump from a roadside assistance truck and drove about 15 miles
> before the engine died and I had to pull to the side of the road. The
> rest of the trip was made on the rear of a flatbed courtesy of AAA.
> Prior to losing all power, I noticed the headlights getting dim and
the
> radio volume declining. The ammeter was way over to the right in the
> discharge zone.
> The staff at Sears tested my battery this morning and told me it was
shot
> (it was 3.5 years old). I purchased a DieHard Gold and installed it.
> The car starts, and the ammeter is smack in the middle while driving.
> I'm pretty sure the problem was the battery but used Dan Masters'
manual
> to run a quick test on the alternator. The battery is putting out
12.8
> volts (normal). With the car running at 1500+rpm and the headlamps
on,
> the voltage at the positive battery terminal is 14.14 volts. When I
> switch on the other elect stuff, it fluctuates between about 12.85 and
> 13.15.
> Next, I tested the voltage at the brown/ white alternator wire. I got
> 14.38 volts with the headlamps on and the car at 1500+ rpm. Switching
on
> the other elects gave me a range of 12.95- 13.10.
> I tested the battery with the car off and got 12.8 volts at the
positive
> terminal and at the brown/red wire at the regulator.
> Finally, I grounded the brown/ yellow wire to the alternator with the
key
> in the on position and got a good strong glow from the ign light.
> One other piece of information, I have a new wiring harness in the
front
> and rear.
> So now my question. Is my alternator healthy? Is the 14.38 at the
back
> of the unit enough or is it borderline. Could this be the reason for
my
> battery going belly-up?
> Finally, according to Dan's neat book, "all of the current used by
your
> car is supplied solely by the alternator". Does this mean that a
healthy
> alternator should have prevented my car from stalling? Or does the
> faulty battery cause a break in the system?
> Thanks.
>
> Peter Macholdt
> '68 TR250
>
>
________________________________________________________________________
> Peter Macholdt
> (609) 466-6458
> 117 West Prospect Street
> Hopewell, New Jersey 08525
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