M
Michael Echemann
Guest
Robert:
The generator is just fine. It's stood up for 35+ years and unless you want to
run mega options with the ignition off keep your amphi stock. They may not be
state of the art but your amphi doesn't have computer chips either now does it.
An amphi in proper condition lives well off it's generator and one shouldn't
notice any difference. I've never heard of one generator problem in all these
years. It's over kill in my opinion and a waste of time unless you want
positive ground for other reasons. If so, you can change that and keep the
generator anyway. Here is a link you might want to look at.
http://www.oconnorclassics.com/MISC/miscframe.htm
Russ: I'd recommend the FloJet 4125. You can mount it with minor adjustments
right in the same spot as the original too. It's not using an impeller so you
can run it dry and comes with an inline filter which is fantastic for checking
it. Here is a link for you to check out:
http://www.pyacht.com/
Mike
----- Original Message -----
From: Ed Price
To: amphicar-lovers@yahoogroups.com
Sent: Wednesday, January 08, 2003 3:04 AM
Subject: Re: [amphicar-lovers] generator or alternator
----- Original Message -----
From: Robert
To: amphicar-lovers@yahoogroups.com
Sent: Tuesday, January 07, 2003 8:35 PM
Subject: [amphicar-lovers] generator or alternator
I respect the alternator conversion. But my question is, "Is it worth the
effort?" It seems to me that the original system is adequate. But only a
fool would go on a trip where headlights may be needed without bringing a
spare generator and voltage regulator. It seems that the cost of these
spares is far less than the effort and expense needed to convert to an
alternator. Am I wrong?
Rob Vondracek
Rob:
I'm not sure I understand what you're saying, so let me address some things
one at a time.
First, a generator / voltage regulator is inherently less reliable than an
alternator. In an alternator, you have a slotted commutator rotating under two
carbon brushes. As each brush goes past each insulating slot between the
conductive commutator pads, there is a momentary electrical arc. This arc
creates electrical noise, and also works to erode the commutator pads,
insulation and carbon brushes. In an alternator, there are continuous slip-rings
with carbon brushes. There's much less arcing, and wear is greatly reduced.
In the voltage regulator, there are at least two electromagnets. The one which
regulates generator output has an armature (the spring-loaded moveable pole
piece) which is constantly "dancing" on its electrical contacts. The duty cycle
of this "dance" controls the generator field current, which in turn controls the
generator output. This contact "dance" is actually a mechanical pulse-width
modulation scheme. Needless to say, the continuous switching causes RF noise,
and slowly erodes the contacts. An alternator simply does not have an external
mechanical voltage regulator, again, making the alternator system inherently
more reliable.
OTOH, automotive generator / voltage regulator technology had quite a while to
mature, so its reliability got to a fairly decent level. It's just that
alternators are better. There's no checking the alternator brushes and cleaning
the voltage regulator contacts. Wiring is simpler, less copper is used, there's
no need to provide "real-estate" room in the engine compartment for the voltage
regulator (because it's not there), and, an alternator is smaller and lighter
than a comparable-rated generator.
The big appeal of an alternator is that, at low RPM, it will put out more
current that a generator. Just as an exercise, let's look at the power budget in
an operating Amphi. (I'm making some estimates here, but I think the numbers are
good.) Let's say you are cruising along at a modest 1800 RPM. The engine
electricals need about 4 amps, the battery is taking 2 amps of charge, and the
radio is taking another amp. Total system load is 7 amps, and the generator can
supply this, so everything is fine. But then the bilge pump goes on, drawing 8
amps. Now the total system load is 15 amps, and the generator can only supply
about 9 amps, so there's now a net drain on the battery of 6 amps. And, if you
were to slow down to idle, the generator could only supply maybe 4 amps, so then
there would be a net drain of 11 amps on the battery. Now, a battery in good
condition could supply 11 amps for several hours.
Look at the ratings; the Amphi generator is rated at a maximum of 21 amps (at
maybe 3500 engine RPM). A plain vanilla Chevy alternator would be rated at 55
amps. The alternator gives you much more safety margin, and the margin gets
bigger at the low RPM range.
Now, about your trip plans. <g> Now, I can understand the idea of having your
own spare on a road trip if you have an unusual car that doesn't show up in any
mechanic's parts book. I can't imagine bringing a spare generator & voltage
regulator along on a trip. But, if you have to worry about your generator that
much, you should replace it before going anywhere. And, if you replaced it with
an alternator, especially a very common one like something from a mid-eighties
GM, then you could find a replacement anywhere you go. (Don't carry heavy spare
parts, your credit card will work just fine.)
Finally, the effort. Well, the conversion isn't all that hard, and you do it
only once. If it was mid-summer, and I didn't mind the headlights dimming
whenever I stepped on the brake, then I wouldn't bother. But, if you are already
tearing into other Amphi jobs in mid-winter, I think the alternator conversion
is a prudent improvement.
Regards,
Ed
El Cajon, CA
67 Rust Guppy
[Non-text portions of this message have been removed]
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[Non-text portions of this message have been removed]
The generator is just fine. It's stood up for 35+ years and unless you want to
run mega options with the ignition off keep your amphi stock. They may not be
state of the art but your amphi doesn't have computer chips either now does it.
An amphi in proper condition lives well off it's generator and one shouldn't
notice any difference. I've never heard of one generator problem in all these
years. It's over kill in my opinion and a waste of time unless you want
positive ground for other reasons. If so, you can change that and keep the
generator anyway. Here is a link you might want to look at.
http://www.oconnorclassics.com/MISC/miscframe.htm
Russ: I'd recommend the FloJet 4125. You can mount it with minor adjustments
right in the same spot as the original too. It's not using an impeller so you
can run it dry and comes with an inline filter which is fantastic for checking
it. Here is a link for you to check out:
http://www.pyacht.com/
Mike
----- Original Message -----
From: Ed Price
To: amphicar-lovers@yahoogroups.com
Sent: Wednesday, January 08, 2003 3:04 AM
Subject: Re: [amphicar-lovers] generator or alternator
----- Original Message -----
From: Robert
To: amphicar-lovers@yahoogroups.com
Sent: Tuesday, January 07, 2003 8:35 PM
Subject: [amphicar-lovers] generator or alternator
I respect the alternator conversion. But my question is, "Is it worth the
effort?" It seems to me that the original system is adequate. But only a
fool would go on a trip where headlights may be needed without bringing a
spare generator and voltage regulator. It seems that the cost of these
spares is far less than the effort and expense needed to convert to an
alternator. Am I wrong?
Rob Vondracek
Rob:
I'm not sure I understand what you're saying, so let me address some things
one at a time.
First, a generator / voltage regulator is inherently less reliable than an
alternator. In an alternator, you have a slotted commutator rotating under two
carbon brushes. As each brush goes past each insulating slot between the
conductive commutator pads, there is a momentary electrical arc. This arc
creates electrical noise, and also works to erode the commutator pads,
insulation and carbon brushes. In an alternator, there are continuous slip-rings
with carbon brushes. There's much less arcing, and wear is greatly reduced.
In the voltage regulator, there are at least two electromagnets. The one which
regulates generator output has an armature (the spring-loaded moveable pole
piece) which is constantly "dancing" on its electrical contacts. The duty cycle
of this "dance" controls the generator field current, which in turn controls the
generator output. This contact "dance" is actually a mechanical pulse-width
modulation scheme. Needless to say, the continuous switching causes RF noise,
and slowly erodes the contacts. An alternator simply does not have an external
mechanical voltage regulator, again, making the alternator system inherently
more reliable.
OTOH, automotive generator / voltage regulator technology had quite a while to
mature, so its reliability got to a fairly decent level. It's just that
alternators are better. There's no checking the alternator brushes and cleaning
the voltage regulator contacts. Wiring is simpler, less copper is used, there's
no need to provide "real-estate" room in the engine compartment for the voltage
regulator (because it's not there), and, an alternator is smaller and lighter
than a comparable-rated generator.
The big appeal of an alternator is that, at low RPM, it will put out more
current that a generator. Just as an exercise, let's look at the power budget in
an operating Amphi. (I'm making some estimates here, but I think the numbers are
good.) Let's say you are cruising along at a modest 1800 RPM. The engine
electricals need about 4 amps, the battery is taking 2 amps of charge, and the
radio is taking another amp. Total system load is 7 amps, and the generator can
supply this, so everything is fine. But then the bilge pump goes on, drawing 8
amps. Now the total system load is 15 amps, and the generator can only supply
about 9 amps, so there's now a net drain on the battery of 6 amps. And, if you
were to slow down to idle, the generator could only supply maybe 4 amps, so then
there would be a net drain of 11 amps on the battery. Now, a battery in good
condition could supply 11 amps for several hours.
Look at the ratings; the Amphi generator is rated at a maximum of 21 amps (at
maybe 3500 engine RPM). A plain vanilla Chevy alternator would be rated at 55
amps. The alternator gives you much more safety margin, and the margin gets
bigger at the low RPM range.
Now, about your trip plans. <g> Now, I can understand the idea of having your
own spare on a road trip if you have an unusual car that doesn't show up in any
mechanic's parts book. I can't imagine bringing a spare generator & voltage
regulator along on a trip. But, if you have to worry about your generator that
much, you should replace it before going anywhere. And, if you replaced it with
an alternator, especially a very common one like something from a mid-eighties
GM, then you could find a replacement anywhere you go. (Don't carry heavy spare
parts, your credit card will work just fine.)
Finally, the effort. Well, the conversion isn't all that hard, and you do it
only once. If it was mid-summer, and I didn't mind the headlights dimming
whenever I stepped on the brake, then I wouldn't bother. But, if you are already
tearing into other Amphi jobs in mid-winter, I think the alternator conversion
is a prudent improvement.
Regards,
Ed
El Cajon, CA
67 Rust Guppy
[Non-text portions of this message have been removed]
Yahoo! Groups Sponsor
ADVERTISEMENT
THE AMPHICAR-LOVERS LIST
~~~~~~~~~~~~~~~~~~~~~~~
Before posting requests for information, please check the List
Archives:
http://www.escribe.com/automotive/amphicar/search.html
For more information about this List and other available services
visit:
http://groups.yahoo.com/group/amphicar-lovers/
To UNsubscribe from this List, just send a blank email to:
amphicar-lovers-unsubscribe@yahoogroups.com
Any other issues may be addressed to the List owner (Mike Israel) at:
amphicar770@yahoo.com
Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
[Non-text portions of this message have been removed]