With respect, the problem with that page is that no one mentions the
fact that too high a voltage is indeed a problem, although a much less
common one than too low a voltage <g>
Unless the engine was still quite cold at that point (like 0C), the 15v
indication probably does indicate a problem with the alternator. (Well,
actually the regulator, but since it's inside the alternator on a TR6
In theory, the voltmeter reads both the alternator output voltage and
the battery voltage, which are the same because they are connected
directly together. In practice, there is always a little voltage drop
through the wires, so when the alternator is charging, the voltmeter
reads somewhere inbetween. Since there is no way for the battery to put
out that much voltage, it must be coming from the alternator.
The problem is that now the battery is being severely overcharged. That
means the water in the electrolyte is being converted to hydrogen and
oxygen, which can explode or more likely just spray battery acid all
over your engine compartment. Then of course, once enough of the
electrolyte is boiled off, the battery is no good.
My advice is to change the alternator soonest, and don't be surprised if
your battery fails in the near future.
Bryce Milton wrote:
> I found a link to some good info on this on The Triumph Web:
> ----- Original Message -----
> From: "G Spencer" <email@example.com>
> > Ok, so while driving my 73 TR6 in hard to work this morning at highway
> > speeds I notice the Volt gauge reading 15 close to the red. While at idle
> > its in the middle. What exactly is this measuring? Any why the high
> > reading while at highway speeds? I'm guessing it's the output of the Alt,
> > is the high reading bad?