Well, I ran out bright and early before running off to work and the wire to
the coil is plain white. I measured the resistance from the fuse block to
the coil and, after cleaning the fuse to get good contact, read .2 ohms. I
think I'll stop by NAPA on my way into work and pick up a stretch of 10 or
12 gauge wire and jumper the piece anyway.
Also, I think I may have made a serious misstatement. Once I opened the
hood I realized my recollection of the poles on the coil was backwards. I
have 8 volts on the negative terminal, not the positive. I didn't want to
wake the neighbors by running the car this early in the driveway while
checking the + voltage, but I am sure it is in the neighborhood of 12.
(Neighbors bedroom window is only about 5 feet from my drive.)
So I guess this means we're back to the alternator? BTW, yes, this is a 69.
Jim Altman jaltman@altlaw.com Illigitimi non Carborundum
http://www.altlaw.com/metro/jaltman.html 69-TR6#CC28754L W4UCK
-----Original Message-----
From: DANMAS@aol.com [mailto:DANMAS@aol.com]
Sent: Tuesday, September 29, 1998 11:08 PM
To: Jim Altman
Subject: Re: Have been chasing the wrong item?
In a message dated 98-09-29 21:17:18 EDT, you write:
> I noticed previously that the voltage on the plus
> side of the coil, engine running, is only about 8 volts with everything
off.
> I had consigned that to the fact that the on/off cycle of the coil was
> having me read something on the order of a sawtooth wave with Digital DC
> volt meter. So I concluded I should read something quite a bit below
13-14
> as I am sure I am reading average rather than peak volts. Are you saying
I
> should read 14 on the coil in spite of the duty cycle of the coil?
Jim,
I think we have found your problem. You should be getting the same voltage
on
the coil as you have on the battery. The duty cycle will not be seen on the
positive post of the coil, only on the negative. The duty cycle will also be
seen in the coil current, but even then, it will be confusing due to the
nature of the coil/capacitor combination, and the fact that the current rise
and fall in the coil is non linear.
Evidently, the wiring harness has been replaced at some time, and a harness
for a later model was used (yours is a '69, right?). The later models have a
ballast resister built into the coil circuit, which will reduce the voltage
to
about 8 volts or so, too low for the sport coil. One quick way to tell -
what
color is the wire to the positive post ofd the coil? It should be white. If
it
is white with a yellow stripe, then you have the ballast resister.
Or, perhaps, a separate ballast resistor has been added?
Try this test. When the engine is idling roughly, with all the electrical
accessories on, take a piece of wire and connect it directly from the
battery
positive post to the coil positive post. I'm certain the idle will smooth
out.
If it does, then we need to make a permanent fix, which is very easy to do.
Simply run a wire from the positive post of the coil to the spare terminal
on
the fuse box where the white wire is attached. Just leave the existing wire
attached to the coil.
There may be an even easier way to do it than that, if your car has a
starter
relay. If so, just lift the white/yellow wire from the relay, and connect it
to the spare terminal mentioned above. That's it! No other changes are
required.
Of course, things are not always as shown on the Triumph diagram, so you may
not have a spare terminal at the white wire connection - there may be more
than one white wire attached here. If so, you will have to make a splice
connection, or get one of the "piggyback" connectors at the local auto
supply
store.
For more info on the ballast resister, check:
http://www.vtr.org/maintain/ballast.html
Let me know what you find when you make the test.
Dan
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