8V92 alternator questions

[g_man1146]

Hi Don,

When I got Blue Thunder the alternator fault light would come on
frequently. BB told me that the internal voltage regulators in the
alternators were not closely matched and when one alternator cut out
due to the voltage level being satisfied it triggered a fault.
Turning on a load such as headlights triggered the alternator to
start and the light went out. The fault light would cycle on and
off. The "fix" was to install a time delay relay so a fault would
have to be present for 15-30 minutes or so before the light would
come on. Reasoning being that if the alternator really was bad, it
would stay bad long enough to light the LED. I mention this because
you may find the time delay relay inside the dash and wonder. There
should be documentation of this modification in the blue box. If the
relay circuit is still there, you may have a bad alternator. My
recollection is that both alternators output similar amperage until
one cut out.

I didn't forget your pictures and found many. Unfortunately I have
prints only, no negatives or digital files and am attempting to find
a service that will scan them all so I can send you the files. If I
don't find that, I can send them all to you and you can copy the
ones you want and return the originals to me.

Rich D. '99LXi43' CT


--- In WanderlodgeForum@yahoogroups.com, "Don Bradner"
wrote:
>
> I've got a few questions after I describe what I'm seeing on my
dual-alternator 8V92:
>
> After starting, the voltage is somewhat below 13, and alt2 is
running about 50 amps. Alt1 is essentially zero, although there is a
slight upward blip when changing the display from alt2 to both.
>
> Voltage slowly rises, and after quite a distance (100 miles or
more) the voltage is in the 13.5 range. At around that time, the
Fault light comes on. Alt2 at this point is running around 25 amps,
and there is no apparent increase in the both position.
>
> What do other 8V92 dual-alternator owners see for charge rates, 1,
2, and both? I'm presuming the zero/near zero is telling me I have a
bad alternator, but is the 50 amps from Alt2 also low? If it is,
what does that mean?
>
> Does anyone know, on theirs, which alternator is 1 and which is 2?
Front top, or back by the bumper?
>
> Don Bradner
> 90 PT40 "Blue Thunder"
>