A couple of weeks ago, Josh Kablotsky wrote:
> When I tried to start the MG, I experienced a problem that began
> appearing in October. Now and then, the car wouldn't start. It's as
> if the battery were dead -- I put in a new battery after the engine
> rebuild last winter. I heard the solenoid click, the engine turn for
> a fraction of a second, the lights dim, and then nothing.
I'm a couple of weeks behind in reading my British car mail, so this is
probably old news. But this sounds exactly like what my '72 TR6 is doing.
My TR6 refused to start and acted dead twice. First, after I'd just
sprayed contact cleaner all over behind the dashboard (I actually
intended to spray it only at the rheostat that controls the dash lights,
but I know it spread beyond there). I got in to start the car, and
there was a split second of power, and then zero. As if my
fully-charged battery had gone flat in that split second. I assumed
some of the contact cleaner had got where it shouldn't and caused a
pretty serious short.
I let the contact cleaner dry while I charged the (disconnected)
battery. After that, the car started and ran fine (and the rheostat
worked better, though still not very well).
I thought that was that, until a few weeks later I stopped at a store on
the way home from work, one very rainy night. I got back to my car, and
the same thing; a brief moment of power, and then nothing. I jumped the
car, and it ran fine all the way home with the lights and windshield
wipers running. After pulling into the garage I tried to restart the
car, and as expected, I got nothing.
I've had another problem with the car which I believe is unrelated; my
headlights blow a 15-amp (I think) fuse more and more frequently. First
it only happened in the rain, and I assumed there was a bad connection
at the lights that, when wet, was shorting. But this started happening
even in dry weather. Now it's to the point where, if I leave the
headlights on for more than 15 minutes or so, they're sure to blow a
fuse.
Because of this, I parked my car in November, the last time it refused
to start, and haven't driven it since. In the intervening months,
through all this bitter cold weather, a voice in my head was trying to
whisper something about dead batteries and cold weather; today when I
tried to recharge the battery, of course, it dawned on my that the
battery was ruined by freezing. Or at least, that's what I suspect,
because it was a pretty new Die-Hard. Sears confirmed that it's ruined
and kindly discounted a purchase towards a new one.
My assumption is that the regulator built into the alternator is fried.
The alternator puts out plenty of power, and it'll run the car just
fine; but it's not charging the battery. The relatively strong battery
held on for several weeks between the first time the car died and
second, running only on the charge I'd given it. The "sudden" loss of
power from the battery was just an illusion--it'd been dying for weeks,
and I never noticed till it was dead.
This suspicion was somewhat confirmed yesterday when I jump started the
car. I connected the cables and let the donor car idle for several
minutes to build up a charge in the battery (this was before I realized
the battery was toast). If I turned the ignition to "run", the ammeter
showed a slight discharge as the fuel pump was energized. Once I
started the car, the ammeter showed a moderate charge; but once I
disconnected the jumper cables, the ammeter showed no charge or
discharge. At this point, the car was running off the alternator, which
wasn't even trying to charge the battery.
Josh shows a lot more electrical savvy than me with his line of
reasoning--I hate electrical work, it totally confuses me, and it scares
me to death:
> Do I have a short in the starter?
-> Then why would the jump start do it?
> Is my starter solenoid misbehaving?
-> If the contacts were dirty, wouldn't it act as an open, not a short?
> Is my almost new battery the problem?
-> Why did it take 6 months to start acting up?
> Is it the charging system?
-> Having it not start doesn't seem connected to driving for any time.
> A starter ground problem?
-> Again, wouldn't it act as an open?
But I have a multimeter, and if someone can give me a few pointers,
maybe I can sort this out. If any of you have the answer to this
problem, please mail me directly. If you already sent replies to Josh
through the list, I'll read them within the next couple of weeks---but
if you don't mind, please mail answers directly to me if you have
suggestions, as I'd rather not wait the 3 weeks it's going to take me to
catch up on all the old Britcar mail I'm still wading through.
Thanks!
Kevin Riggs
________________________________________________________________________
Intergraph Corporation TEL: (205) 730-3074
Mailstop: GD3003 FAX: (205) 730-3453
Huntsville, AL 35894-0001 rkriggs@ingr.com
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