8V92 alternator questions

[Don Bradner]

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"

[smquandt]

Don



Previous discussion on this or the other Wanderlodge forum was that there
might be a bad ground to ALT #1. I have the same problem but my 93 PT is in
Florida until Friday when I go to retrieve it. I'm going to pull the floor
when I get home. I had the Alt. rebuilt last summer when it was pulled just
as a preventive maintenance issue, still read no voltage when replaced but
didn't have time last summer to tackle the problem.



Steve Quandt

Iron Mountain, MI

93 PT40



-----Original Message-----
From: WanderlodgeForum@yahoogroups.com
[mailto:WanderlodgeForum@yahoogroups.com] On Behalf Of Don Bradner
Sent: Tuesday, February 20, 2007 5:58 PM
To: wanderlodgeforum@yahoogroups.com
Subject: [WanderlodgeForum] 8V92 alternator questions



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"





[Non-text portions of this message have been removed]

[Bob & Carol Howald`]

Don: I've had a few alternator problem's with my 93pt a few years
ago. It was always the # 2 alternator, that's the one on the left
side of the engine . After replacing the alternator 2 time's bluebird
finally convinced me to just eliminate it and use the # 1 alternator
only, it's the one on the right side next to the bumper. I've not had
any problem's since going to the single alternator. I use it to
charge 8--series 31 house batteries plus the 3 engine start. Never a
problem since and we do some dry camping. I believe that the problem
with the # 2 alternator is due to the fact that the grounding cable's
are too small. I now carry that extra alternator in the part's box
in case I need it. It's much easier to replace the # 1 alternator
than # 2. Also..A common problem is that one fail's and you don't
know it till the other one fail's and then you have nothing. The
alternator check switch #1--#2 is generally not reliable I would not
spend much time or much trust in the integrity of this switch.

Work's for me;;;;;;;Bob 93pt-40










- 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"
>

[Leroy Eckert]

Don:
I probably will not be much help because I chased that switch ghost for a year.
I finally gave up and unplugged the fault light. It doesn't concern me any more.
My number 1 alternator is the one on top of the engine accessable under the bed.

After I start typically my amp guage will be in the 150 range with the switch in
dual. It progressively decreases while driving and the volt meter is around
13.5v. Once stable the amp reading is 50 amp at all times.

I periodically check my alternators for output with a meter.

If you find the ghost, please advise.

Leroy Eckert
1990 WB-40"Smoke N Mirrors"
Niceville, FL






----- Original Message -----
From: Don Bradner
To: wanderlodgeforum@yahoogroups.com
Sent: Tuesday, February 20, 2007 5:57 PM
Subject: [WanderlodgeForum] 8V92 alternator questions


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"





[Non-text portions of this message have been removed]

[Don Bradner]

That's helpful. It actually hadn't occurred to me that I might be chasing a
switch ghost - I figured the number 1 (which you say is the one under the bed,
but for Bob it is the one by the bumper ???) was actually bad, but the fault
didn't trip until the total amperage dropped low enough.

With a charge rate of 150 amps I would expect your batteries to hit full charge
fairly quickly? That mine takes hours and 100 miles or more is a good part of
why I thought the 50 amp rate might be right. We are not talking about
discharged batteries - these are one-month-old 6-volt AGM Lifelines that are
full charged at the start, and only have to make up for the current used in
starting the engine. I would expect 160-amp chargers, even if only one is
working, to get it up in a matter of minutes with a high charge-rate that
quickly falls off. I'm not seeing that.

I know just enough about alternators to be dangerous. I understand exciter
current and such. I don't understand how an alternator would be working, but
working way less than full output.

On 2/20/2007 at 8:46 PM Leroy Eckert wrote:

>Don:
>I probably will not be much help because I chased that switch ghost for a
>year. I finally gave up and unplugged the fault light. It doesn't concern
>me any more. My number 1 alternator is the one on top of the engine
>accessable under the bed.
>
>After I start typically my amp guage will be in the 150 range with the
>switch in dual. It progressively decreases while driving and the volt
>meter is around 13.5v. Once stable the amp reading is 50 amp at all
>times.
>
>I periodically check my alternators for output with a meter.
>
>If you find the ghost, please advise.
>
>Leroy Eckert
>1990 WB-40"Smoke N Mirrors"
>Niceville, FL
>
>
>
>
>
>
> ----- Original Message -----
> From: Don Bradner
> To: wanderlodgeforum@yahoogroups.com
> Sent: Tuesday, February 20, 2007 5:57 PM
> Subject: [WanderlodgeForum] 8V92 alternator questions
>
>
> 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"
>
>
>
>
>
>[Non-text portions of this message have been removed]
>
>
>
>
>Yahoo! Groups Links
>
>
>

Don Bradner
http://www.arcatapet.net

[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"
>

[Leroy Eckert]

I tend to agree with your concerns. My alternator behind the rear bumper failed
and I was not aware of it. On the road my #1 alternator failed and left me with
the generator. That really wasn't a problem.. The #1 alternator was a 160amp
variety if I recall and when I pulled the #2 it was 135amp. I put a 160amp
alternator back. All of this is from memory at the moment, I could look in my
paper work and verify. It has been almost 3 years without problems. I even had
Coachcraft by McDonald, Columbus GA a BB service center look at the switch for
me when I retrofitted the Wabasto and they could not figure it out either. I
changed all the wires, cleaned connections and nothing changed at the switch.
Soooo, I unplugged the !@#$ light. A little bit of redneck engineering there.
Kinda like if the rattle bothers you , turn up the radio. lol

You have 6v batteries? Interesting mine are 12v, bank of 6.
A lot of weird differences in these coaches, eh?

Typically, in terms of time, depending if the a/c, lights, inverter output,
etc. are utilized, it may take 30 minutes for the amp meter to settle at 50 amp
in my coach. I'd suggest starting the coach and checking the output of both
alternators, if they have output you may be ok. Also, check the rating, someone
may have placed a lesser output value on the coach. 160's are not easy to find
and are not cheap. Just a thought.

Leroy Eckert
1990 WB-40"Smoke N Mirrors"
Niceville, FL

Leroy Eckert
1990 WB-40"Smoke N Mirrors"
Niceville, FL


----- Original Message -----
From: Don Bradner
To: WanderlodgeForum@yahoogroups.com
Sent: Tuesday, February 20, 2007 9:06 PM
Subject: Re: [WanderlodgeForum] 8V92 alternator questions


That's helpful. It actually hadn't occurred to me that I might be chasing a
switch ghost - I figured the number 1 (which you say is the one under the bed,
but for Bob it is the one by the bumper ???) was actually bad, but the fault
didn't trip until the total amperage dropped low enough.

With a charge rate of 150 amps I would expect your batteries to hit full
charge fairly quickly? That mine takes hours and 100 miles or more is a good
part of why I thought the 50 amp rate might be right. We are not talking about
discharged batteries - these are one-month-old 6-volt AGM Lifelines that are
full charged at the start, and only have to make up for the current used in
starting the engine. I would expect 160-amp chargers, even if only one is
working, to get it up in a matter of minutes with a high charge-rate that
quickly falls off. I'm not seeing that.

I know just enough about alternators to be dangerous. I understand exciter
current and such. I don't understand how an alternator would be working, but
working way less than full output.

On 2/20/2007 at 8:46 PM Leroy Eckert wrote:

>Don:
>I probably will not be much help because I chased that switch ghost for a
>year. I finally gave up and unplugged the fault light. It doesn't concern
>me any more. My number 1 alternator is the one on top of the engine
>accessable under the bed.
>
>After I start typically my amp guage will be in the 150 range with the
>switch in dual. It progressively decreases while driving and the volt
>meter is around 13.5v. Once stable the amp reading is 50 amp at all
>times.
>
>I periodically check my alternators for output with a meter.
>
>If you find the ghost, please advise.
>
>Leroy Eckert
>1990 WB-40"Smoke N Mirrors"
>Niceville, FL
>
>
>
>
>
>
> ----- Original Message -----
> From: Don Bradner
> To: wanderlodgeforum@yahoogroups.com
> Sent: Tuesday, February 20, 2007 5:57 PM
> Subject: [WanderlodgeForum] 8V92 alternator questions
>
>
> 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"
>
>
>
>
>
>[Non-text portions of this message have been removed]
>
>
>
>
>Yahoo! Groups Links
>
>
>

Don Bradner
http://www.arcatapet.net





[Non-text portions of this message have been removed]

[Leroy Eckert]

Interesting, there really is a ghost in there.

Leroy Eckert
1990 WB-40"Smoke N Mirrors"
Niceville, FL



----- Original Message -----
From: g_man1146
To: WanderlodgeForum@yahoogroups.com
Sent: Tuesday, February 20, 2007 9:43 PM
Subject: [WanderlodgeForum] Re: 8V92 alternator questions


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"
>





[Non-text portions of this message have been removed]

[Don Bradner]

Thanks, Rich. I didn't get the blue box - sent you an e-mail a week or so ago
asking if it passed on from you, sounds like it did. I'm going to resend that
e-mail after this one, so let me know if you don't get it.

I'll be home tomorrow; have been somewhat on the road (but sitting a lot in
Arizona) since getting Blue Thunder. Should have a couple of months to go
through everything as carefully as I can to see if I can figure out what's going
on. In 1500 miles the only other thing that has come up was a transient "do not
shift/check tranny" light that occurred towards the end of the long climb up
I-17 near the 6000-foot level. I had left it in Cruise at 62, and it was doing a
lot of up-down shifting. I just backed off and the warnings did not re-occur.
Temps, including tranny temp, were the same as they are the rest of the time
(except when using the retarder, when obviously the transmission temps climb a
lot).

On 2/21/2007 at 3:43 AM g_man1146 wrote:

>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"
>>
>
>
>
>
>
>Yahoo! Groups Links
>
>
>

Don Bradner
http://www.arcatapet.net

[Don Bradner]

This one had 6 12v Group 24s until a bit over a month ago. Swapping out for
6-volt Golf Cart batteries is a common method of increasing capacity. They have
nearly the same footprint as the Group 24, but are taller.

6 Group 24s is 450AH (6*75), while 6 Golf Carts in series-parallel is 660AH
(3*220). Golf Cart batteries are also designed for sustained discharge at
significant output.

The one tradeoff is a loss in high-power output. The Group 24s are rated for 500
Cold-Cranking Amps, while the CCA of a GC battery is 800, so you get 3000
(6*500) vs 2400 (3*800). I worried a bit about that, but reading, and experience
since, indicates that 2000 is plenty for starting an 8V92.

On 2/20/2007 at 9:45 PM Leroy Eckert wrote:

>You have 6v batteries? Interesting mine are 12v, bank of 6.
>A lot of weird differences in these coaches, eh?

Don Bradner
http://www.arcatapet.net