Discussion:
Bobcat 610 Changing to a Chevy Alternator
(too old to reply)
a***@notmail.com
2007-10-29 10:56:55 UTC
I just bought a used Bobcat 610 Skid Loader that does not charge the
battery. It has a generator and 3 wire voltage regulator. Someone
before I bought it really messed up the wiring. In fact I had to
check over the whole thing very carefully because several times it
would kill and I'd see sparks. I carefully capped and taped all bare
wires, several of which went nowhere. The engine runs, so that
verifies the innition system is getting power. However, the battery
drains quickly. I had the battery tested and they said it was fine.
The amp gauge does not work, but I can tell even without it that there
is no charging from the generator. Personally, I always hated those
old generators because of all the excessive wiring to the regulator.
Besides that, I cant even remember how to test the generator and
regulators anymore.

I can get a Chevy alternator at the scrap yard pretty cheap. Rather
than waste hours trying to figure out how to test the generator and
determine if all the messed up wiring is connected the way it should
be, it seems easier to just install the chevy alternator. The
question arises whether it will physically fit to the brackets. Does
anyone know? One other thing. It seems to me that the old generators
REQUIRED the amp gauge as a resistance source. Is that true, and if
so, will the alternator need it too? I tend to wonder if the dead amp
gauge is the reason there is no charging now????

Thanks

By the way, anyone know if there are Chilton books or other such books
made for Bobcats?

Alvin
Jack Hunt
2007-10-29 19:36:51 UTC
Post by a***@notmail.com
The
question arises whether it will physically fit to the brackets. Does
anyone know?
Without knowing the dimensions of either your brackets or the alternator you're
going to pick up, the answer is no, nobody knows. The other answer is that you
can make anything line up if you want to bad enough. A GM one-wire alternator
is a common fix for troublesome charging systems.
Post by a***@notmail.com
One other thing. It seems to me that the old generators
REQUIRED the amp gauge as a resistance source. Is that true
No, and no. You don't need an ammeter. A voltmeter is good, it will tell you
if your battery is being charged or not while you're running.
Post by a***@notmail.com
I tend to wonder if the dead amp
gauge is the reason there is no charging now?
I tend to wonder if the cut wires have anything to do with it?

I once put a Toyota alternator and a GM regulator on a 1946 Allis Chalmers
tractor and it worked just fine. It didn't have an ammeter or voltmeter but it
kept the battery charged and ran the headlights.

Whatever you do, DO NOT take the battery cable off while the engine is running.
The only thing that tests is how long it will run on an open circuit before it
fries your entire charging system and the answer is "a few seconds at best,
immediately at worst".

--
Jack
Bob Noble
2007-10-30 05:32:46 UTC
Post by Jack Hunt
Whatever you do, DO NOT take the battery cable off while the engine is running.
The only thing that tests is how long it will run on an open circuit before it
fries your entire charging system and the answer is "a few seconds at best,
immediately at worst".
An open circuit?
If the battery is removed, that takes the voltage off the field of the
alternator and there will be no voltage anywhere.
So, I must not be understanding something?
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by a***@notmail.com
The
question arises whether it will physically fit to the brackets. Does
anyone know?
Without knowing the dimensions of either your brackets or the alternator you're
going to pick up, the answer is no, nobody knows. The other answer is that you
can make anything line up if you want to bad enough. A GM one-wire alternator
is a common fix for troublesome charging systems.
Post by a***@notmail.com
One other thing. It seems to me that the old generators
REQUIRED the amp gauge as a resistance source. Is that true
No, and no. You don't need an ammeter. A voltmeter is good, it will tell you
if your battery is being charged or not while you're running.
Post by a***@notmail.com
I tend to wonder if the dead amp
gauge is the reason there is no charging now?
I tend to wonder if the cut wires have anything to do with it?
I once put a Toyota alternator and a GM regulator on a 1946 Allis Chalmers
tractor and it worked just fine. It didn't have an ammeter or voltmeter but it
kept the battery charged and ran the headlights.
--
Jack
Glenn
2007-10-30 13:45:45 UTC
Maybe it's like an experience I had some 60 yrs ago. A
cable jumped off the battery while driving, on my pride
and joy, 37 Ford Tutor and EVERY bulb in the car burned
out. This was during the day when nothing was turned
on. Even my pride and joy, my sealed beam head lights,
both dim and bright. No one, including electrical
engineers that I have known, have really explained it
well. "Well it arced." Hell, I know that, but nothing
was turned on.
Post by Bob Noble
Post by Jack Hunt
Whatever you do, DO NOT take the battery cable off
while the engine is running.
The only thing that tests is how long it will run on
an open circuit before it
fries your entire charging system and the answer is
"a few seconds at best,
immediately at worst".
An open circuit?
If the battery is removed, that takes the voltage off
the field of the alternator and there will be no
voltage anywhere.
So, I must not be understanding something?
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
On Mon, 29 Oct 2007 05:56:55 -0500,
Post by a***@notmail.com
The
question arises whether it will physically fit to
the brackets. Does
anyone know?
Without knowing the dimensions of either your
brackets or the alternator you're
going to pick up, the answer is no, nobody knows.
The other answer is that you
can make anything line up if you want to bad enough.
A GM one-wire alternator
is a common fix for troublesome charging systems.
Post by a***@notmail.com
One other thing. It seems to me that the old
generators
REQUIRED the amp gauge as a resistance source. Is
that true
No, and no. You don't need an ammeter. A voltmeter
is good, it will tell you
if your battery is being charged or not while you're
running.
Post by a***@notmail.com
I tend to wonder if the dead amp
gauge is the reason there is no charging now?
I tend to wonder if the cut wires have anything to
do with it?
I once put a Toyota alternator and a GM regulator on
a 1946 Allis Chalmers
tractor and it worked just fine. It didn't have an
ammeter or voltmeter but it
kept the battery charged and ran the headlights.
--
Jack
Steve Barker
2007-10-30 18:50:46 UTC
Again, not possible. If the lighting circuits were not on, then there's NO
way they could burn out the bulbs. Also, it's not likely they would burn
out even if they WERE turned on.

s
Maybe it's like an experience I had some 60 yrs ago. A cable jumped off
the battery while driving, on my pride and joy, 37 Ford Tutor and EVERY
bulb in the car burned out. This was during the day when nothing was
turned on. Even my pride and joy, my sealed beam head lights, both dim
and bright. No one, including electrical engineers that I have known,
have really explained it well. "Well it arced." Hell, I know that, but
nothing was turned on.
Glenn
2007-10-30 19:05:36 UTC
Ahh but it DID.

WHY would I make something like that up?

This isn't a STORY I heard of. It was MY car I was
the one paying for and replacing the bulbs, even in the
dash board where you can't hardly reach them..
Post by Steve Barker
Again, not possible. If the lighting circuits were
not on, then there's NO way they could burn out the
bulbs. Also, it's not likely they would burn out
even if they WERE turned on.
s
Post by Glenn
Maybe it's like an experience I had some 60 yrs ago.
A cable jumped off the battery while driving, on my
pride and joy, 37 Ford Tutor and EVERY bulb in the
car burned out. This was during the day when
nothing was turned on. Even my pride and joy, my
sealed beam head lights, both dim and bright. No
one, including electrical engineers that I have
known, have really explained it well. "Well it
arced." Hell, I know that, but nothing was turned
on.
jjfjksdf
2007-10-31 00:47:44 UTC
Post by Glenn
Ahh but it DID.
WHY would I make something like that up?
This isn't a STORY I heard of. It was MY car I was the one paying for
and replacing the bulbs, even in the dash board where you can't hardly
reach them..
You should post that story over in sci.electronics.misc or
sci.electronics.repair and see what they have to say.
Steve Barker
2007-10-31 01:20:53 UTC
I rekon the same reason so many people make up so many stories. Cause they
want to be included in the conversation? I really don't know. I hear
dozens of stories each day that people have just flat made up. It's the
american way i guess.

s
Post by Glenn
Ahh but it DID.
WHY would I make something like that up?
This isn't a STORY I heard of. It was MY car I was the one paying for
and replacing the bulbs, even in the dash board where you can't hardly
reach them..
Glenn
2007-10-31 02:01:52 UTC
Hmmm. I'm being called a liar by an idiot who doesn't
know what he's talking about. Did it happen as I
described it? Yes. Do I give a damn if anybody
believes it? No. Do I need conversation? Not with
the likes of you.
Post by Steve Barker
I rekon the same reason so many people make up so many
stories. Cause they want to be included in the
conversation? I really don't know. I hear dozens of
stories each day that people have just flat made up.
It's the american way i guess.
s
Post by Glenn
Ahh but it DID.
WHY would I make something like that up?
This isn't a STORY I heard of. It was MY car I was
the one paying for and replacing the bulbs, even in
the dash board where you can't hardly reach them..
Steve Barker
2007-10-31 13:59:13 UTC
Oh, so now I'm an idiot for being reasonable and logical? OK.


cya

s


plonk!
Hmmm. I'm being called a liar by an idiot who doesn't know what he's
talking about. Did it happen as I described it? Yes. Do I give a damn
if anybody believes it? No. Do I need conversation? Not with the likes
of you.
Post by Steve Barker
I rekon the same reason so many people make up so many stories. Cause
they want to be included in the conversation? I really don't know. I
hear dozens of stories each day that people have just flat made up. It's
the american way i guess.
s
Post by Glenn
Ahh but it DID.
WHY would I make something like that up?
This isn't a STORY I heard of. It was MY car I was the one paying for
and replacing the bulbs, even in the dash board where you can't hardly
reach them..
Bob Noble
2007-11-06 03:52:05 UTC
Hi Glen,
I don't think you are a liar. As a matter of fact I think I know what
happened to your lights.
Three things one must know to understand what happened to your car.
The first is that if you put a voltage on a coil and take it off, the coil
must discharge, no matter what. The field on the coil will collapse and it
will discharge somewhere.
The second is that a battery has a lot of amps to supply to a circuit.
The third is that making and breaking a circuit such as with a bouncing
battery cable, causes huge voltage spikes to occur in the circuit.

Now, if the battery cable just fell off, that wouldn't be a problem, except
your car would stop.
But you said the cable bounced. That causes large over voltage spikes to
occur, just from the cable making and breaking contact.
That means the coil voltage would make and break, with higher than normal
voltage on it from the jumping cable.

This would cause the coil to get a bit excited and since the battery has
huge amounts of current to supply, this means the coil would be discharging
at a very high voltage and with a lot of current.
Light switches off would mean nothing to this kind of thing. The current
would just jump any switch contacts like they weren't even there. Remember,
the coil has to discharge big time, fast, as it's going to get another
bounce and repeat it again, until it self destructs something.

This kind of current would be enough to take out all your light filaments
and anything else in the circuit.
Actually, it's the only thing I know that could take the filaments out that
way.

So, that's my deductions from what was said about this thing. Not something
one could put a meter on to find out. :O)
--
Bob Noble
http://www.sonic.net/bnoble
Post by Glenn
Ahh but it DID.
WHY would I make something like that up?
This isn't a STORY I heard of. It was MY car I was the one paying for
and replacing the bulbs, even in the dash board where you can't hardly
reach them..
Post by Steve Barker
Again, not possible. If the lighting circuits were not on, then there's
NO way they could burn out the bulbs. Also, it's not likely they would
burn out even if they WERE turned on.
s
Maybe it's like an experience I had some 60 yrs ago. A cable jumped off
the battery while driving, on my pride and joy, 37 Ford Tutor and EVERY
bulb in the car burned out. This was during the day when nothing was
turned on. Even my pride and joy, my sealed beam head lights, both dim
and bright. No one, including electrical engineers that I have known,
have really explained it well. "Well it arced." Hell, I know that, but
nothing was turned on.
Jack Hunt
2007-11-06 03:58:57 UTC
Post by Bob Noble
So, that's my deductions from what was said about this thing. Not something
one could put a meter on to find out.
So if a loose battery cable can cause huge voltage spikes and blow bulbs, why
can't it fry solid state regulators? Diodes?

And why would it "stop" if the cable fell off when people here have stated that
they've been running their stuff for years without a battery?

Just trying to tie up the loose ends.

Can't wait to see the answer to this one.

--
Jack
Bob Noble
2007-11-06 04:31:40 UTC
Well Jack,
Maybe it wouldn't stop. That car was before my time and likely had an old
generator that I may have wrongly suspected needed the battery to charge
it's field.
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by Bob Noble
So, that's my deductions from what was said about this thing. Not something
one could put a meter on to find out.
So if a loose battery cable can cause huge voltage spikes and blow bulbs, why
can't it fry solid state regulators? Diodes?
And why would it "stop" if the cable fell off when people here have stated that
they've been running their stuff for years without a battery?
Just trying to tie up the loose ends.
Can't wait to see the answer to this one.
--
Jack
Jack Hunt
2007-11-06 13:14:37 UTC
Post by Bob Noble
Maybe it wouldn't stop. That car was before my time and likely had an old
generator that I may have wrongly suspected needed the battery to charge
it's field.
Bob, I'm beginning to suspect that we're on the same team here. Please read
this whole thing before you make up your mind. You've seen what static
discharge does to components. Read on and see what over-voltage does to other
systems in the car.

The old saying was that you have to have power to make power. You had to have a
battery to begin with but after you got it going, you could run without it. That
was true with later DC generators and was partially true with the AC generators.
I was a general line automotive technician during the time when America changed
from DC to AC generators. I received professional training from GM, Ford, and
Chrysler on their charging systems. They all strongly cautioned against
removing the cable while it was running, for the following reasons:

The older DC generators were the only ones that you could safely take the cable
off, for three reasons. They didn't have anything solid state to risk getting
cooked from a voltage spike, they didn't have enough capacity to make a lot of
excess voltage or amperage due to their limitation from a permanent magnet
setup, and it was only 6 volts to start with. The car with the blown light
bulbs almost certainly involved the secondary of the ignition coil.

The amount of electricity generated is limited by the strength of the magnetic
field and speed of rotation (actually the speed of the field vs the conductor
but let's not split hairs here). In DC generators the magnets were fixed to the
shell of the unit and the armature rotated inside the permanent magnetic field.
With these permanent magnet setups, it may have been possible to bump-start one
without a battery in place, I never tried. The only thing that could increase
the output was to rotate it faster which changed the amount of times that a
conductor was passed through a magnetic field. This, of course, had limits. If
you rotate it fast enough, the armature would sling apart.

Later DC generators used coils instead of magnets which increased the output
because the magnetic field was stronger than a permanent magnet. When these hit
the market, you could no longer generate power without a using battery to get
the system going. Some smaller industrial engines used the generator as the
starter, the starter drive being the fan belt. The permanent magnets were
replaced by very heavy magnetic coils that when energized by battery power,
caused the armature to rotate. There was a limited amount of space for the
magnetic coils and they wouldn't crank the heavier engines due to their limited
cranking power. They never got fast enough to sling it apart. Gear drive
starters used a much higher gear reduction in relation to engine speed and if a
starter drive hung in the flywheel when the engine caught and sped up, it would
sling the starter armature apart if it wasn't shut off pretty quickly. Most
later starters have overrunning clutch setups to try to protect them but if that
fails, you're looking at a new starter.

The AC generators, or alternators (GM used to call them Delcotrons) don't have
permanent magnets. The rotor is a couple of, for lack of a better term, cups,
that partially surround a coil of wire. They're actually multi-pole magnets
when in operation. The more poles you have in your magnetic field, the more
times it passes over the conductor to generate electricity. When current is
applied to this coil it magnetizes the cups which rotate inside the stator, a
mass of loops of wire. The more loops you have, the more power is generated
when the field passes over them. In the older GM alternators it was possible to
increase the output just by putting in a stator with more wire loops. Why they
made different output alternators was always a mystery to me, but they did.

The output of the alternator is varied by changing the amount of power supplied
to the rotor. If voltage goes up, the magnet get stronger, output goes up which
increases system voltage which increases rotor voltage which increases power
output until something releases its internal smoke*.

*electronic devices run on Internal Smoke. If you see something release its
Internal Smoke, catch the smoke and take it with the device to a qualified
technician. He will reinsert the smoke so it will work again.

<foghorn> That's a joke, son. Don't pop a diode. </foghorn>

It was a vicious cycle that kept increasing until something popped. Some
systems popped just as soon as the cable was pulled off. Some built heat for a
while and then something failed. Some degraded and decreased output until the
maximum voltage was below what it took to smoke something. Pulling a cable off
on an AC system is very harmful to the system. Eventually it will kill or
degrade the system until it will no longer maintain the battery.

Sure the main diodes are heavy duty but they still fail. That's why they're
replaceable. Now they come in a preset tree that must be replaced as a unit but
in the old days they were pressed into a couple of horseshoe shaped heat sinks
and could be individually changed on an arbor press. In some models they're
built in to the regulator and it gets changed all in one lump, along with the
brush holders.

Nobody rebuilds alternators in the shop anymore. You can buy a rebuilt one
cheaper than you can buy the parts and do it yourself. But I used to rebuild a
lot of them. I'd just replace whatever was bad. Now when you get a rebuilt
one, you get a new diode tree, new brushes on the slip rings of the rotor, new
bearings, and a new voltage regulator. You still have the same old rotor and
stator unless they're bad. I've seen many stators overheat and short together or
short to ground. I've seen a few burn open. I've seen one or two rotors fail
in either short or open condition but a bad rotor coil is quite rare.

The arguments about JD bulldozer systems don't apply here. We're talking about
Chevy car alternators which were designed to keep the service department busy.
The JD stuff was designed to keep working under harsh conditions and so was
heavy enough to run a long time in overload condition. That's why industrial
parts are so massive. They don't have any greater output than a car alternator,
but they're built to take a lot more abuse.

Due to cost cutting and planned obsolescence, car stuff is designed to be as
light duty as possible and so has a higher failure rate when abused. If they
built the stuff as heavy as tractor systems, the overall weight and bulk would
be a lot more, the cost would be a lot more, and the service department would
look like it was staffed with Maytag Repairmen. It's a sad fact that Detroit
makes almost as much money fixing their cars than they do selling them and we
all pay for it. That's why they try to keep repairs so mysterious or
complicated that you can't do it at home.

When some new system comes out, the public won't be able to buy a service manual
or test equipment for it until at least two years or until it is replaced by a
newer system requiring new manuals and test equipment. Part of the reason I got
out of mechanics was the ever-changing systems that were pushed on us in the
80s, complete re-designs every year, more schools to go to, more stuff to
remember, more test equipment to buy. We had to get our test equipment from the
manufacturer and that crap wasn't cheap but it was useless the next year.

Add to that some goober pulling off his battery cable and frying an engine and
transmission* control computer buried deep in the bowels of the dashboard
requiring a day of taking stuff apart just to reach...no wonder I have high
blood pressure. ;-)

*Since the early 90s or earlier, automatic transmissions have been computer
controlled. Gone are the vacuum modulator valves, the governor valve, most of
the valve body. Replaced by throttle position sensors, speed sensors, and other
electronic stuff that is very sensitive to over-voltage.

I'll say one more thing and then I'm done with the subject. Go ahead and pull
the cable off when it's running. Somewhere there's a mechanic who needs the
money. He can figure out why your fuel injection system started acting funny or
your transmission started shifting differently or not at all, or your timing
advance doesn't advance anymore, or your air conditioner stopped working, not
long after you "tested" your charging system.

But it ain't me, not any more.

--
Jack
Bob Noble
2007-11-06 17:59:33 UTC
Hi Jack,
I think your points are well taken.
Remember this is just a discussion and discussions are where we can learn,
hopefully. :O)
I was wondering if you'd jump on the static charge thing and compare what
you where saying with it and you did. :O)
I won't let anyone else mechanic my stuff and it's not likely I'll be
taking any battery cables off to test anything. But they can come off
occasionally and maybe it'll fry something?
Because there are different designs out there, taking the battery cable off
while the engine is running, may or may not cause a problem, but why take a
chance.
I also appreciate your persistence, it's what prodded me into thinking about
Glen's ol story.

Thanks,
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by Bob Noble
Maybe it wouldn't stop. That car was before my time and likely had an old
generator that I may have wrongly suspected needed the battery to charge
it's field.
Bob, I'm beginning to suspect that we're on the same team here. Please read
this whole thing before you make up your mind. You've seen what static
discharge does to components. Read on and see what over-voltage does to other
systems in the car.
The old saying was that you have to have power to make power. You had to have a
battery to begin with but after you got it going, you could run without it. That
was true with later DC generators and was partially true with the AC generators.
I was a general line automotive technician during the time when America changed
from DC to AC generators. I received professional training from GM, Ford, and
Chrysler on their charging systems. They all strongly cautioned against
The older DC generators were the only ones that you could safely take the cable
off, for three reasons. They didn't have anything solid state to risk getting
cooked from a voltage spike, they didn't have enough capacity to make a lot of
excess voltage or amperage due to their limitation from a permanent magnet
setup, and it was only 6 volts to start with. The car with the blown light
bulbs almost certainly involved the secondary of the ignition coil.
The amount of electricity generated is limited by the strength of the magnetic
field and speed of rotation (actually the speed of the field vs the conductor
but let's not split hairs here). In DC generators the magnets were fixed to the
shell of the unit and the armature rotated inside the permanent magnetic field.
With these permanent magnet setups, it may have been possible to bump-start one
without a battery in place, I never tried. The only thing that could increase
the output was to rotate it faster which changed the amount of times that a
conductor was passed through a magnetic field. This, of course, had limits. If
you rotate it fast enough, the armature would sling apart.
Later DC generators used coils instead of magnets which increased the output
because the magnetic field was stronger than a permanent magnet. When these hit
the market, you could no longer generate power without a using battery to get
the system going. Some smaller industrial engines used the generator as the
starter, the starter drive being the fan belt. The permanent magnets were
replaced by very heavy magnetic coils that when energized by battery power,
caused the armature to rotate. There was a limited amount of space for the
magnetic coils and they wouldn't crank the heavier engines due to their limited
cranking power. They never got fast enough to sling it apart. Gear drive
starters used a much higher gear reduction in relation to engine speed and if a
starter drive hung in the flywheel when the engine caught and sped up, it would
sling the starter armature apart if it wasn't shut off pretty quickly.
Most
later starters have overrunning clutch setups to try to protect them but if that
fails, you're looking at a new starter.
The AC generators, or alternators (GM used to call them Delcotrons) don't have
permanent magnets. The rotor is a couple of, for lack of a better term, cups,
that partially surround a coil of wire. They're actually multi-pole magnets
when in operation. The more poles you have in your magnetic field, the more
times it passes over the conductor to generate electricity. When current is
applied to this coil it magnetizes the cups which rotate inside the stator, a
mass of loops of wire. The more loops you have, the more power is generated
when the field passes over them. In the older GM alternators it was possible to
increase the output just by putting in a stator with more wire loops. Why they
made different output alternators was always a mystery to me, but they did.
The output of the alternator is varied by changing the amount of power supplied
to the rotor. If voltage goes up, the magnet get stronger, output goes up which
increases system voltage which increases rotor voltage which increases power
output until something releases its internal smoke*.
*electronic devices run on Internal Smoke. If you see something release its
Internal Smoke, catch the smoke and take it with the device to a qualified
technician. He will reinsert the smoke so it will work again.
<foghorn> That's a joke, son. Don't pop a diode. </foghorn>
It was a vicious cycle that kept increasing until something popped. Some
systems popped just as soon as the cable was pulled off. Some built heat for a
while and then something failed. Some degraded and decreased output until the
maximum voltage was below what it took to smoke something. Pulling a cable off
on an AC system is very harmful to the system. Eventually it will kill or
degrade the system until it will no longer maintain the battery.
Sure the main diodes are heavy duty but they still fail. That's why they're
replaceable. Now they come in a preset tree that must be replaced as a unit but
in the old days they were pressed into a couple of horseshoe shaped heat sinks
and could be individually changed on an arbor press. In some models they're
built in to the regulator and it gets changed all in one lump, along with the
brush holders.
Nobody rebuilds alternators in the shop anymore. You can buy a rebuilt one
cheaper than you can buy the parts and do it yourself. But I used to rebuild a
lot of them. I'd just replace whatever was bad. Now when you get a rebuilt
one, you get a new diode tree, new brushes on the slip rings of the rotor, new
bearings, and a new voltage regulator. You still have the same old rotor and
stator unless they're bad. I've seen many stators overheat and short together or
short to ground. I've seen a few burn open. I've seen one or two rotors fail
in either short or open condition but a bad rotor coil is quite rare.
The arguments about JD bulldozer systems don't apply here. We're talking about
Chevy car alternators which were designed to keep the service department busy.
The JD stuff was designed to keep working under harsh conditions and so was
heavy enough to run a long time in overload condition. That's why industrial
parts are so massive. They don't have any greater output than a car alternator,
but they're built to take a lot more abuse.
Due to cost cutting and planned obsolescence, car stuff is designed to be as
light duty as possible and so has a higher failure rate when abused. If they
built the stuff as heavy as tractor systems, the overall weight and bulk would
be a lot more, the cost would be a lot more, and the service department would
look like it was staffed with Maytag Repairmen. It's a sad fact that Detroit
makes almost as much money fixing their cars than they do selling them and we
all pay for it. That's why they try to keep repairs so mysterious or
complicated that you can't do it at home.
When some new system comes out, the public won't be able to buy a service manual
or test equipment for it until at least two years or until it is replaced by a
newer system requiring new manuals and test equipment. Part of the reason I got
out of mechanics was the ever-changing systems that were pushed on us in the
80s, complete re-designs every year, more schools to go to, more stuff to
remember, more test equipment to buy. We had to get our test equipment from the
manufacturer and that crap wasn't cheap but it was useless the next year.
Add to that some goober pulling off his battery cable and frying an engine and
transmission* control computer buried deep in the bowels of the dashboard
requiring a day of taking stuff apart just to reach...no wonder I have high
blood pressure. ;-)
*Since the early 90s or earlier, automatic transmissions have been computer
controlled. Gone are the vacuum modulator valves, the governor valve,
most of
the valve body. Replaced by throttle position sensors, speed sensors, and other
electronic stuff that is very sensitive to over-voltage.
I'll say one more thing and then I'm done with the subject. Go ahead and pull
the cable off when it's running. Somewhere there's a mechanic who needs the
money. He can figure out why your fuel injection system started acting funny or
your transmission started shifting differently or not at all, or your timing
advance doesn't advance anymore, or your air conditioner stopped working, not
long after you "tested" your charging system.
But it ain't me, not any more.
--
Jack
Jack Hunt
2007-11-06 18:09:31 UTC
Post by Bob Noble
I won't let anyone else mechanic my stuff and it's not likely I'll be
taking any battery cables off to test anything.
Even with all the complication, charging systems are easy to check. Test
battery voltage with the engine off. Should be 12.5 or greater. Start the
engine and test again. Should be 13.5 to 14.5. If it's not, you have problems.
Post by Bob Noble
But they can come off
occasionally and maybe it'll fry something?
A good open end wrench will fix that. ;-)

--
Jack
Bob Noble
2007-11-06 06:54:35 UTC
Post by Jack Hunt
So if a loose battery cable can cause huge voltage spikes and blow bulbs, why
can't it fry solid state regulators? Diodes?
You are asking me to do some more deducing here.
Not a loose connection, but a bouncing one we were talking about, which is
much worse.

The diodes used in auto applications are very rugged to start with. I'd bet
they have at least a 600 volt reverse spec, so to start, the voltage would
have to exceed that. Engineers know about frying components and they also
use other electronic parts to clamp voltages and other methods to prevent
things like you imply from happening. For instance, a regulator is just
that. It tryst to keep the voltage to some regulated voltage and it's parts
would have to have a high reverse voltage spec to survive in these kinds of
applications anyway.

Chances are the high voltage and current that ate Glens car lights just
wouldn't happen on today's vehicles.

And by the way, not all engines will run without the battery. Some will and
some won't. Just depends on the design.
I've experienced both types, now that I think about it. :O)
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by Bob Noble
So, that's my deductions from what was said about this thing. Not something
one could put a meter on to find out.
And why would it "stop" if the cable fell off when people here have stated that
they've been running their stuff for years without a battery?
Just trying to tie up the loose ends.
Can't wait to see the answer to this one.
--
Jack
Steve Barker
2007-11-06 04:16:21 UTC
How do you account for the fact that we routinely short out plug wires (to
test cylinder balance) with our 12v test lamps and don't burn that bulb out?

steve
Post by Bob Noble
Hi Glen,
I don't think you are a liar. As a matter of fact I think I know what
happened to your lights.
Three things one must know to understand what happened to your car.
The first is that if you put a voltage on a coil and take it off, the coil
must discharge, no matter what. The field on the coil will collapse and it
will discharge somewhere.
The second is that a battery has a lot of amps to supply to a circuit.
The third is that making and breaking a circuit such as with a bouncing
battery cable, causes huge voltage spikes to occur in the circuit.
Now, if the battery cable just fell off, that wouldn't be a problem,
except your car would stop.
But you said the cable bounced. That causes large over voltage spikes to
occur, just from the cable making and breaking contact.
That means the coil voltage would make and break, with higher than normal
voltage on it from the jumping cable.
This would cause the coil to get a bit excited and since the battery has
huge amounts of current to supply, this means the coil would be
discharging at a very high voltage and with a lot of current.
Light switches off would mean nothing to this kind of thing. The current
would just jump any switch contacts like they weren't even there.
Remember, the coil has to discharge big time, fast, as it's going to get
another bounce and repeat it again, until it self destructs something.
This kind of current would be enough to take out all your light filaments
and anything else in the circuit.
Actually, it's the only thing I know that could take the filaments out
that way.
So, that's my deductions from what was said about this thing. Not
something one could put a meter on to find out. :O)
--
Bob Noble
http://www.sonic.net/bnoble
Post by Glenn
Ahh but it DID.
WHY would I make something like that up?
This isn't a STORY I heard of. It was MY car I was the one paying for
and replacing the bulbs, even in the dash board where you can't hardly
reach them..
Post by Steve Barker
Again, not possible. If the lighting circuits were not on, then there's
NO way they could burn out the bulbs. Also, it's not likely they would
burn out even if they WERE turned on.
s
Maybe it's like an experience I had some 60 yrs ago. A cable jumped off
the battery while driving, on my pride and joy, 37 Ford Tutor and EVERY
bulb in the car burned out. This was during the day when nothing was
turned on. Even my pride and joy, my sealed beam head lights, both dim
and bright. No one, including electrical engineers that I have known,
have really explained it well. "Well it arced." Hell, I know that,
but nothing was turned on.
Bob Noble
2007-11-06 04:37:13 UTC
Easy.
When the system is running properly on the proper voltage, there isn't the
huge amounts of current available to fry anything.
Shorting out the plug wire is shorting out the secondary field of the coil.
You are not messing with the primary field. Remember, the bouncing battery
cable is what caused the huge voltage spikes. Shorting a plug wire wouldn't
cause a huge voltage spike in the primary coil.
--
Bob Noble
http://www.sonic.net/bnoble
Post by Steve Barker
How do you account for the fact that we routinely short out plug wires (to
test cylinder balance) with our 12v test lamps and don't burn that bulb out?
steve
Post by Bob Noble
Hi Glen,
I don't think you are a liar. As a matter of fact I think I know what
happened to your lights.
Three things one must know to understand what happened to your car.
The first is that if you put a voltage on a coil and take it off, the
coil must discharge, no matter what. The field on the coil will collapse
and it will discharge somewhere.
The second is that a battery has a lot of amps to supply to a circuit.
The third is that making and breaking a circuit such as with a bouncing
battery cable, causes huge voltage spikes to occur in the circuit.
Now, if the battery cable just fell off, that wouldn't be a problem,
except your car would stop.
But you said the cable bounced. That causes large over voltage spikes to
occur, just from the cable making and breaking contact.
That means the coil voltage would make and break, with higher than normal
voltage on it from the jumping cable.
This would cause the coil to get a bit excited and since the battery has
huge amounts of current to supply, this means the coil would be
discharging at a very high voltage and with a lot of current.
Light switches off would mean nothing to this kind of thing. The current
would just jump any switch contacts like they weren't even there.
Remember, the coil has to discharge big time, fast, as it's going to get
another bounce and repeat it again, until it self destructs something.
This kind of current would be enough to take out all your light filaments
and anything else in the circuit.
Actually, it's the only thing I know that could take the filaments out
that way.
So, that's my deductions from what was said about this thing. Not
something one could put a meter on to find out. :O)
--
Bob Noble
Steve Barker
2007-11-07 02:10:38 UTC
it does, however, send the secondary voltage through the test light bulb.
Post by Bob Noble
Easy.
When the system is running properly on the proper voltage, there isn't the
huge amounts of current available to fry anything.
Shorting out the plug wire is shorting out the secondary field of the
coil. You are not messing with the primary field. Remember, the bouncing
battery cable is what caused the huge voltage spikes. Shorting a plug wire
wouldn't cause a huge voltage spike in the primary coil.
--
Bob Noble
Glenn
2007-11-06 14:47:01 UTC
You're right. If the washboard road shook the cable
off, there's no question but it bounced on the terminal
a few times before it fell off to the side. Your
theory is the best I have seen or heard so far and
that's over a 60 year period.

For the younger posters, we need to remember that this
was a 6V system, positive ground, 6V generator not
alternator, probably 8 to 10A, I don't think they even
knew what a diode was back then. [g]
Post by Bob Noble
Hi Glen,
I don't think you are a liar. As a matter of fact I
think I know what happened to your lights.
Three things one must know to understand what
happened to your car.
The first is that if you put a voltage on a coil and
take it off, the coil must discharge, no matter what.
The field on the coil will collapse and it will
discharge somewhere.
The second is that a battery has a lot of amps to
supply to a circuit.
The third is that making and breaking a circuit such
as with a bouncing battery cable, causes huge voltage
spikes to occur in the circuit.
Now, if the battery cable just fell off, that
wouldn't be a problem, except your car would stop.
But you said the cable bounced. That causes large
over voltage spikes to occur, just from the cable
making and breaking contact.
That means the coil voltage would make and break,
with higher than normal voltage on it from the
jumping cable.
This would cause the coil to get a bit excited and
since the battery has huge amounts of current to
supply, this means the coil would be discharging at a
very high voltage and with a lot of current.
Light switches off would mean nothing to this kind of
thing. The current would just jump any switch
contacts like they weren't even there. Remember, the
coil has to discharge big time, fast, as it's going
to get another bounce and repeat it again, until it
self destructs something.
This kind of current would be enough to take out all
your light filaments and anything else in the
circuit.
Actually, it's the only thing I know that could take
the filaments out that way.
So, that's my deductions from what was said about
this thing. Not something one could put a meter on to
find out. :O)
Jack Hunt
2007-11-06 18:23:31 UTC
Post by Glenn
For the younger posters
I'd give you 20 bucks just for calling me younger. Younger guys were around
when Al Gore invented the internet. I was around when Ike invented scorched
earth.
Post by Glenn
we need to remember that this
was a 6V system, positive ground, 6V generator not
alternator, probably 8 to 10A
You still had an ignition coil putting out at least 10,000 volts and that
voltage had to go somewhere every time the points opened. Modern ignition
systems are over 60,000 volts now, and if you get your hand into a leaky plug
boot, you'll invent new words.

They made some 6v alternators in the mid 60s for people who wanted to change
over to a higher amperage system. The problem was that most owners changed to
12v while they were at it and the 6v alternators never caught on. I even saw
some positive ground alternators but for the life of me, I couldn't figure out
why someone would want one.

I changed a '52 Ford truck to 12v and left the 6v starter on it. That starter
would scare that old flathead to death when it hit. I also put a 12v charging
system on a '40something Allis Chalmers leaving the 6v starter. You could just
about plow using just the starter. ;-)

If you really want some fun, change a 6v positive ground truck to 12v negative
ground and try to use the 6v positive ground radio. It can be done but it's not
easy. ;-)
Post by Glenn
I don't think they even
knew what a diode was back then. [g]
Oh, they've had diodes for as long as they've had radios. But in those days a
diode was a vacuum tube in the back of your radio. The younger crowd doesn't
remember waiting for the radio or TV to warm up before it would work.

--
Jack
Bob Noble
2007-11-01 05:51:41 UTC
My goodness, we got excited. :O)
Maybe that's what brings out discussion.
I've also learned over the years of fixing things not to doubt the stories.
There is usually an answer if you just had all the pieces.
Now, my JD450C bulldozer runs when the battery cable falls off, so I can
deduce that the alternator is still putting out juice to keep my diesel
solenoid on, without the battery. I also know that a regulated alternator
for twelve volt systems has a maximum regulated output of about 14.6 or so
volts. I've also read many service manuals and can't recall ever seeing any
of them say don't pull the battery cable off while it is running. I'd also
deduce that if disconnecting the battery while the motor was running caused
the wires to fry, there would be zillions of them. This because I have an
opinion of today's modern people, just being key turners and know almost
nothing about what makes anything go.
So, could this happen, I'd have to say, possible, especially on a defective
system. But, I doubt it is a normal type thing.
For sure, most of the time, there is no reason to pull a battery cable off
while the engine is running.
Thanks for all the input.
--
Bob Noble
http://www.sonic.net/bnoble
Maybe it's like an experience I had some 60 yrs ago. A cable jumped off
the battery while driving, on my pride and joy, 37 Ford Tutor and EVERY
bulb in the car burned out. This was during the day when nothing was
turned on. Even my pride and joy, my sealed beam head lights, both dim
and bright. No one, including electrical engineers that I have known,
have really explained it well. "Well it arced." Hell, I know that, but
nothing was turned on.
Post by Bob Noble
Post by Jack Hunt
Whatever you do, DO NOT take the battery cable off while the engine is running.
The only thing that tests is how long it will run on an open circuit before it
fries your entire charging system and the answer is "a few seconds at best,
immediately at worst".
An open circuit?
If the battery is removed, that takes the voltage off the field of the
alternator and there will be no voltage anywhere.
So, I must not be understanding something?
Jack Hunt
2007-11-01 13:48:53 UTC
Post by Bob Noble
I'd also
deduce that if disconnecting the battery while the motor was running caused
the wires to fry, there would be zillions of them. This because I have an
opinion of today's modern people, just being key turners and know almost
nothing about what makes anything go.
At least one of the people here is a certified engine and automatic transmission
rebuilder for Ford.

I never said it would fry wires. I intended to say that it would fry delicate
semiconductors in the charging, ignition, and fuel injection systems but I
realize that's a very long word for you to try to read.

I have put many voltage regulators on vehicles where the owner "tested" it first
by pulling the cable off while it was running. It usually worked the first time
but died the second.

Some idiots even "tested" it again after I fixed it.

Here's something to roll around in your cranial cavern: If you pull off a
battery cable and it doesn't fry everything, what are the chances that your
charging system has been so degraded by your test that it now just barely has
the capacity to keep the engine running, and almost no capacity to keep your
battery charged if you're running headlights?

Here's something else to ponder: WHY DON'T YOU JUST GET A VOLT METER AND STOP
WITH THE STUPID BACKWOODS SHADE TREE DIAGNOSTICS???

A voltmeter can be had for less than $10 but that would require cognitive
thought. I guess that answers the previous question.

--
Jack
Bob Noble
2007-11-02 04:08:20 UTC
I used to work for HP as an electronic engineer.
My job was taking these electronic components apart with hot acid and
microscopes and finding out why they got fried. I've had every part and the
board itself apart down to it's tiniest makeup. That still doesn't make me
an expert on anything.

If I wanted to get out the meters I would, but I don't consider this kind of
stuff deserves the trouble, just for something we are having a discussion
on.
If I pull off the battery cable, it's not likely I'd fry or degrade anything
in the charging system.
So big deal, I said frying wires and you didn't, you said fry the system, I
think.
It's just a discussion Jack.

My stupid deductions are how mechanicing is done. Saves a lot of time.
Sorry, you don't approve.
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by Bob Noble
I'd also
deduce that if disconnecting the battery while the motor was running caused
the wires to fry, there would be zillions of them. This because I have an
opinion of today's modern people, just being key turners and know almost
nothing about what makes anything go.
At least one of the people here is a certified engine and automatic transmission
rebuilder for Ford.
I never said it would fry wires. I intended to say that it would fry delicate
semiconductors in the charging, ignition, and fuel injection systems but I
realize that's a very long word for you to try to read.
I have put many voltage regulators on vehicles where the owner "tested" it first
by pulling the cable off while it was running. It usually worked the first time
but died the second.
Some idiots even "tested" it again after I fixed it.
Here's something to roll around in your cranial cavern: If you pull off a
battery cable and it doesn't fry everything, what are the chances that your
charging system has been so degraded by your test that it now just barely has
the capacity to keep the engine running, and almost no capacity to keep your
battery charged if you're running headlights?
Here's something else to ponder: WHY DON'T YOU JUST GET A VOLT METER AND STOP
WITH THE STUPID BACKWOODS SHADE TREE DIAGNOSTICS???
A voltmeter can be had for less than $10 but that would require cognitive
thought. I guess that answers the previous question.
--
Jack
Jack Hunt
2007-11-02 10:07:12 UTC
Post by Bob Noble
If I pull off the battery cable, it's not likely I'd fry or degrade anything
in the charging system.
Experts like you are what kept food on my table when I was wrenching for a
living. Keep up the good work.

That same panel of experts determined that it's impossible for a bumblebee to
fly. But they sure can jump a long way.

--
Jack
jjfjksdf
2007-11-03 19:08:34 UTC
Post by Bob Noble
I used to work for HP as an electronic engineer.
My job was taking these electronic components apart with hot acid and
microscopes and finding out why they got fried. I've had every part and
the board itself apart down to it's tiniest makeup. That still doesn't
make me an expert on anything.
That sounds like a great job. What kinds of failures did you typically
see?
Bob Noble
2007-11-06 04:28:29 UTC
It was a great job.
I'd say it was a bit like being Sherlock, except I did it to electronic
parts and processes.
Most of the parts and processes I worked on were for production. Each piece
of equipment we made had a bunch of twenty five cent parts in them, but when
produced the whole box sold for over eighty thousand dollars and it took
three different boxes to make a unit.
The problem was the people making the little parts always said the problem
was caused by our production people and the parts where so small nobody
could argue with them. So, another engineer started the Reliability Physics
Lab and hired me to help out. At that time my background was machinist,
electronic.

Most of the problems were manufacturing related as the parts were so small
it was easy to mess up a process in their production.
Likely my biggest case was introducing static discharge to HP. The Space
people knew about it, but industry didn't believe.
Hp has a little sampler diode package that cost 500 dollars. It was one
diode in a metal case. Very high frequency stuff. To get enough good ones
they manufactured twice what they needed to get what they needed.
The diodes were mysteriously getting leaky on the reverse current and
wouldn't work. They would go bad anywhere in the production process, but
especially during the time the tech tested them for completion. Every new
engineer had worked on this for two years before it got to me. This got to
be a huge problem when the total good output dropped to five percent, and
now I heard about it.

I'd done a littlie work with static charge and the first thing I told the
engineer that came to me was I suspect static discharge. He looked at me
disbelieving. So, I went about to prove it. So, I got some failed parts and
did everything to them I could think of and still no proof. One day I was
shooting the bull in the area that the parts were being tested and talking
to the tech who did the testing. He said he couldn't understand it. He'd
test it once and be ok, and test a diode again and it would be bad. At this
time I noted that he didn't have his anti-static wrist strap on nor was he
working on a anti-static work station. These kinds of things were just
starting to be introduced at this time and most people were not believers in
static discharge as a failure mechanism.
Aha. That's it. He was discharging into the diodes and blowing them.
We got some anti-static stuff on him and the failure rate went down to
almost zero.
I always took the greatest satisfaction in solving things others could not.
--
Bob Noble
http://www.sonic.net/bnoble
Post by jjfjksdf
Post by Bob Noble
I used to work for HP as an electronic engineer.
My job was taking these electronic components apart with hot acid and
microscopes and finding out why they got fried. I've had every part and
the board itself apart down to it's tiniest makeup. That still doesn't
make me an expert on anything.
That sounds like a great job. What kinds of failures did you typically
see?
Jack Hunt
2007-11-06 11:42:56 UTC
Post by Bob Noble
He said he couldn't understand it. He'd
test it once and be ok, and test a diode again and it would be bad.
That's the same story I got from people who tested their alternators by pulling
off the battery cable. "Huh? It worked a few minutes ago."

--
Jack
Bob Noble
2007-11-06 18:00:29 UTC
Good one Jack. :O)
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by Bob Noble
He said he couldn't understand it. He'd
test it once and be ok, and test a diode again and it would be bad.
That's the same story I got from people who tested their alternators by pulling
off the battery cable. "Huh? It worked a few minutes ago."
--
Jack
Don Young
2007-11-07 03:02:09 UTC
Maybe it's like an experience I had some 60 yrs ago. A cable jumped off
the battery while driving, on my pride and joy, 37 Ford Tutor and EVERY
bulb in the car burned out. This was during the day when nothing was
turned on. Even my pride and joy, my sealed beam head lights, both dim
and bright. No one, including electrical engineers that I have known,
have really explained it well. "Well it arced." Hell, I know that, but
nothing was turned on.
Post by Bob Noble
Post by Jack Hunt
Whatever you do, DO NOT take the battery cable off while the engine is running.
The only thing that tests is how long it will run on an open circuit before it
fries your entire charging system and the answer is "a few seconds at best,
immediately at worst".
An open circuit?
If the battery is removed, that takes the voltage off the field of the
alternator and there will be no voltage anywhere.
So, I must not be understanding something?
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by a***@notmail.com
The
question arises whether it will physically fit to the brackets. Does
anyone know?
Without knowing the dimensions of either your brackets or the alternator you're
going to pick up, the answer is no, nobody knows. The other answer is
that you
can make anything line up if you want to bad enough. A GM one-wire
alternator
is a common fix for troublesome charging systems.
Post by a***@notmail.com
One other thing. It seems to me that the old generators
REQUIRED the amp gauge as a resistance source. Is that true
No, and no. You don't need an ammeter. A voltmeter is good, it will tell you
if your battery is being charged or not while you're running.
Post by a***@notmail.com
I tend to wonder if the dead amp
gauge is the reason there is no charging now?
I tend to wonder if the cut wires have anything to do with it?
I once put a Toyota alternator and a GM regulator on a 1946 Allis Chalmers
tractor and it worked just fine. It didn't have an ammeter or voltmeter but it
kept the battery charged and ran the headlights.
--
Jack
In all this discussion of a topic I have heard many, many times over in my
60 year career as mechanic, electrician, and electronic technician I have
yet to hear an explanation of how one knows his lights are burned out
without turning them on. The normal thing to do when one suspected a battery
problem was to turn on the lights to see if they would burn and I have seen
some burned out. I don't doubt the stories as such, but I sure would like to
see someone actually demonstrate that he can, at will, burn out the lights
in a car by removing or bouncing the battery cable when the lights are off
or the regulator is working properly. I agree that it is definitely not a
good idea to remove the battery cable when the engine is running. I know
wierd things do happen that we are unable to explain for various reasons.

Don Young

Don Young

Clif Holland
2007-10-30 16:25:30 UTC
In my understanding of the single wire alternator, it once excited, is self
exciting. There is only one wire if you discount the wire for the idiot
light. The alternator senses battery voltage thru that wire and outputs
~14v. If the battery is removed it just cranks up everything to try and
maintain 14v.
--
Clif
Post by Bob Noble
Post by Jack Hunt
Whatever you do, DO NOT take the battery cable off while the engine is running.
The only thing that tests is how long it will run on an open circuit before it
fries your entire charging system and the answer is "a few seconds at best,
immediately at worst".
An open circuit?
If the battery is removed, that takes the voltage off the field of the
alternator and there will be no voltage anywhere.
So, I must not be understanding something?
--
Bob Noble
http://www.sonic.net/bnoble
Post by Jack Hunt
Post by a***@notmail.com
The
question arises whether it will physically fit to the brackets. Does
anyone know?
Without knowing the dimensions of either your brackets or the alternator you're
going to pick up, the answer is no, nobody knows. The other answer is that you
can make anything line up if you want to bad enough. A GM one-wire alternator
is a common fix for troublesome charging systems.
Post by a***@notmail.com
One other thing. It seems to me that the old generators
REQUIRED the amp gauge as a resistance source. Is that true
No, and no. You don't need an ammeter. A voltmeter is good, it will tell you
if your battery is being charged or not while you're running.
Post by a***@notmail.com
I tend to wonder if the dead amp
gauge is the reason there is no charging now?
I tend to wonder if the cut wires have anything to do with it?
I once put a Toyota alternator and a GM regulator on a 1946 Allis Chalmers
tractor and it worked just fine. It didn't have an ammeter or voltmeter but it
kept the battery charged and ran the headlights.
--
Jack
Steve Barker
2007-10-30 18:49:37 UTC
Not true. We've run machines for days without batteries in them.


s
Post by Jack Hunt
Whatever you do, DO NOT take the battery cable off while the engine is running.
The only thing that tests is how long it will run on an open circuit before it
fries your entire charging system and the answer is "a few seconds at best,
immediately at worst".
--
Jack
Jack Hunt
2007-10-31 01:21:50 UTC
Post by Steve Barker
Not true. We've run machines for days without batteries in them.
More data needed. What kind of machine? Gas or diesel? What kind of charging
system? AC or DC? How did you get it started in the first place and was the
charging system operating at all? I used to bump start an old MF 35 diesel
tractor with no battery but it would run with no electricity at all.

Put a volt meter on your battery cables and pull a cable off the battery. See
where the voltage goes to. I don't know about the single wire jobs, but the old
Delco alternators with the external regulator would go to about 50 VAC. I saw a
Leece Neville alternator go to 90 VAC on a test cabinet.

DC generators are a different story. You CAN run them without a battery with no
harm. But I don't know of anything built since the mid 60s that had a DC
generator. Everything is rectified AC these days.

--
Jack
Steve Barker
2007-10-31 13:58:22 UTC
Alternated vehicles. Mostly gas. some diesel. A ford truck here and
there. If the alternator/regulator is working properly, then it won't hurt
it.

s
Post by Jack Hunt
More data needed. What kind of machine? Gas or diesel? What kind of charging
system? AC or DC? How did you get it started in the first place and was the
charging system operating at all? I used to bump start an old MF 35 diesel
tractor with no battery but it would run with no electricity at all.
Put a volt meter on your battery cables and pull a cable off the battery.
See
where the voltage goes to. I don't know about the single wire jobs, but the old
Delco alternators with the external regulator would go to about 50 VAC. I saw a
Leece Neville alternator go to 90 VAC on a test cabinet.
DC generators are a different story. You CAN run them without a battery with no
harm. But I don't know of anything built since the mid 60s that had a DC
generator. Everything is rectified AC these days.
--
Jack
Jack Hunt
2007-10-31 14:55:05 UTC
Post by Steve Barker
If the alternator/regulator is working properly, then it won't hurt
it.
Just for the record, you're full it. You didn't answer the question: How did
you get it started in the first place? An alternator system, without an initial
voltage presence, will not generate any electricity. You had to have a good
battery on it, then pull it off after it was running, which, by the way, is
stupid and I don't believe that you did it.

Here's a task for you. Find ANY automotive service manual that recommends
pulling off the cable as a test. or find any manual that even says "that won't
hurt". We'll wait.

But I won't hold my breath. You'll never complete the task because the text
does not exist.

--
Jack
Clif Holland
2007-10-31 18:11:17 UTC
On Wed, 31 Oct 2007 08:58:22 -0500, "Steve Barker"
Post by Steve Barker
If the alternator/regulator is working properly, then it won't hurt
it.
Just for the record, you're full it. You didn't answer the question: How did
you get it started in the first place? An alternator system, without an initial
voltage presence, will not generate any electricity. You had to have a good
battery on it, then pull it off after it was running, which, by the way, is
stupid and I don't believe that you did it.
Here's a task for you. Find ANY automotive service manual that recommends
pulling off the cable as a test. or find any manual that even says "that won't
hurt". We'll wait.
But I won't hold my breath. You'll never complete the task because the text
does not exist.
--
Jack
I just ignore him. He already called Glenn a liar because his limited
knowledge does not allow him to comprehend what happened. And because he
can't understand it then it's obviously a lie.

Glenn although I can't explain it and neither can anyone else I can believe
it because I've seen other things happen that noone could explain either. It
just comes with getting a little older and wiser.

It's amazing but the older I got the smarter my daddy became.
--
Clif
Glenn
2007-10-31 18:51:25 UTC
Post by Clif Holland
I just ignore him. He already called Glenn a liar
because his limited knowledge does not allow him to
comprehend what happened. And because he can't
understand it then it's obviously a lie.
Glenn although I can't explain it and neither can
anyone else I can believe it because I've seen other
things happen that noone could explain either. It
just comes with getting a little older and wiser.
It's amazing but the older I got the smarter my daddy
became.
One engineer I know of thought maybe the fact that it
was a positive ground, that may have had something to
do with it. I remember I was about a block from home,
our farm was just outside the city limits and the
gravel road was a real washboard. I guess that's what
shook it off.

I liked that old car though, my first. One thing, by
Friday evening, you wanted to drag your foot to get
stopped in time. Every Sat, I would crawl under and
re-adjust the mechanical brakes. It of course had a 6V
generator and the undependable cut out instead of a
voltage regulator. Manifold heater that worked
occasionally. Ahhh memories.
Jack Hunt
2007-11-01 01:34:42 UTC
Post by Glenn
One engineer I know of thought maybe the fact that it
was a positive ground, that may have had something to
do with it.
I don't think that had anything to do with it, but the arc suggestion has some
merit. The old DC generators didn't have the capability to generate much more
than the full charged voltage of a 6V battery, maybe 7 volts or so. But if
there was an arc somewhere like a cutout or a malfunctioning voltage regulator,
that could have contributed to a voltage spike that could have fried your stuff.

Anything is possible. If you had a coil ignition system and not a magneto, you
could have gotten feedback from the secondary to the primary windings and that
would have sent a few thousand volts through the wiring system. Not enough to
cause a fire, but enough to burn out the filament of any bulb that was burning
at the time. If it was enough voltage to jump a small gap, like the distance
between contacts in a headlight switch, that could explain the blown bulbs on a
light system that was supposed to be off.

All it would take would be a stray spark jumping from the rotor button back to
the grounded side of the coil at the breaker points and your whole electrical
system would become a gigantic spark plug.

--
Jack
Don Young
2007-11-01 01:59:34 UTC
On Tue, 30 Oct 2007 13:49:37 -0500, "Steve Barker"
Post by Steve Barker
Not true. We've run machines for days without batteries in them.
More data needed. What kind of machine? Gas or diesel? What kind of charging
system? AC or DC? How did you get it started in the first place and was the
charging system operating at all? I used to bump start an old MF 35 diesel
tractor with no battery but it would run with no electricity at all.
Put a volt meter on your battery cables and pull a cable off the battery.
See
where the voltage goes to. I don't know about the single wire jobs, but the old
Delco alternators with the external regulator would go to about 50 VAC. I saw a
Leece Neville alternator go to 90 VAC on a test cabinet.
DC generators are a different story. You CAN run them without a battery with no
harm. But I don't know of anything built since the mid 60s that had a DC
generator. Everything is rectified AC these days.
--
Jack
IF the regulator is working properly, the voltage will not exceed about 14.4
volts. That's what the regulator does, regulate the voltage to prevent it
from going any higher than needed to fully charge the battery. If the
regulator uses external sensing and the sensing lead is disconnected or if
the regulator is not working, the voltage can get to over 100 volts. There
is a device available which disconnects the battery and bypasses the
regulator to permit using a 12V alternator to operate 120 volt lights and
tools equipped with series motors, such as drills and saws.

The old three brush generators which used only a cutout and no regulator
will definitely burn out the bulbs if the battery becomes disconnected while
running at high speed. It is not a good idea to disconnect the battery even
with a regulator as there is always a risk that the regulator will
malfunction and cause electrical damage.

Don Young