"Wayne.B" wrote in message
...
On Thu, 31 Oct 2013 16:37:37 -0400, "Flying Pig"
wrote:

from a blower we used to use on the alternator
before we figured out what was causing the horrible failure rate

====

I have my own tales of alternator failures, finally resolved. Don't
think I've heard about yours. Our failures were caused by the *very*
large house bank (8 HD golf cart batts in series-parallel), which
appeared to the alternator more or less as a dead short when they were
in need of a serious recharge. The solution was a controlled series
resistance consisting of 10 ft of #4 wire which was just enough to
limit the current inrush to acceptable levels.

Mine was a case of a 1/2" pulley on the alternator when the design was for
3/8, and not using a corrugated belt which would flex at high speeds,
dissipating heat. The mount-twiddling was a mere benefit, rather than just
solution

Went from 10 to 200 hour belt changes, and the 10s were usually catastrophic
(breakage)...

I've recently shortened the belt to get more mileage out of the adjustment,
as the belts I took off weren't worn out, just stretched out.

However, I only have 880AH, and my alternator isn't doing the work; it's
solar and wind, plus occasional application of a Honda eu2000i to the
charger.

Good workaround!

L8R

Skip

--

Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery !
Follow us at http://groups.yahoo.com/group/TheFlyingPigLog
and/or http://groups.google.com/group/flyingpiglog

When a man comes to like a sea life, he is not fit to live on land.
- Dr. Samuel Johnson

On Fri, 1 Nov 2013 11:30:16 -0400, "Flying Pig"
wrote:

"Wayne.B" wrote in message
.. .
On Thu, 31 Oct 2013 16:37:37 -0400, "Flying Pig"
wrote:

from a blower we used to use on the alternator
before we figured out what was causing the horrible failure rate

====

I have my own tales of alternator failures, finally resolved. Don't
think I've heard about yours. Our failures were caused by the *very*
large house bank (8 HD golf cart batts in series-parallel), which
appeared to the alternator more or less as a dead short when they were
in need of a serious recharge. The solution was a controlled series
resistance consisting of 10 ft of #4 wire which was just enough to
limit the current inrush to acceptable levels.

Mine was a case of a 1/2" pulley on the alternator when the design was for
3/8, and not using a corrugated belt which would flex at high speeds,
dissipating heat. The mount-twiddling was a mere benefit, rather than just
solution

Went from 10 to 200 hour belt changes, and the 10s were usually catastrophic
(breakage)...

I've recently shortened the belt to get more mileage out of the adjustment,
as the belts I took off weren't worn out, just stretched out.

However, I only have 880AH, and my alternator isn't doing the work; it's
solar and wind, plus occasional application of a Honda eu2000i to the
charger.

Good workaround!


===

I've had good luck with Gates "Green Stripe" belts, available at NAPA
auto parts. 200 hours is still not all that good. There must still
be another issue somewhere. Having experienced any number of belt and
alternator failure modes, I can tell you that a nice clean belt break
is preferable to a whining, squealing burn up which is throwing off
black rubber bits and smoke in the engine compartment.

Our *big* alternator is now a 320 amp Leece-Neville fire truck unit
driven by three belts. It has over 500 hours so far with no belt
changes or signs of premature wear. Even with the current limiting
resistor, the alternator causes the DD 6-71 diesel to audibly grunt
for a split second when I switch in the house bank.

"Wayne.B" wrote in message
...

I've had good luck with Gates "Green Stripe" belts, available at NAPA
auto parts. 200 hours is still not all that good. There must still
be another issue somewhere. Having experienced any number of belt and
alternator failure modes, I can tell you that a nice clean belt break
is preferable to a whining, squealing burn up which is throwing off
black rubber bits and smoke in the engine compartment.

Our *big* alternator is now a 320 amp Leece-Neville fire truck unit
driven by three belts. It has over 500 hours so far with no belt
changes or signs of premature wear. Even with the current limiting
resistor, the alternator causes the DD 6-71 diesel to audibly grunt
for a split second when I switch in the house bank.

Since 200 hours represents a couple of years or so, I'm not terribly worried
:{)) Our belts are Gates, too, but from NAPA and wherever we can find it;
they're toothed/cogged/scalloped on the inside, and heat, ever since, has
not been an issue.

But we DO have belt dust, a bit. Never had a squealer, though; our
alternator's only 70A and as far as I can tell, it's never challenged the
belt, particularly.

In the cases where we have to motor, it will fill the bank from wherever
we've gotten it down to - usually not less/more, depending on how you count,
than 70%, but otherwise, it's loafing. Our solar and wind do all the heavy
lifting...

L8R

Skip

--

Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery !
Follow us at http://groups.yahoo.com/group/TheFlyingPigLog
and/or http://groups.google.com/group/flyingpiglog

When a man comes to like a sea life, he is not fit to live on land.
- Dr. Samuel Johnson

"Wayne.B" wrote:

Our *big* alternator is now a 320 amp Leece-Neville fire truck unit
driven by three belts. It has over 500 hours so far with no belt
changes or signs of premature wear. Even with the current limiting
resistor, the alternator causes the DD 6-71 diesel to audibly grunt
for a split second when I switch in the house bank.
-----------------------------------------------------
There was a time in my life when I was a Leece-Neville design
engineer.

Back in those days the large alternators (200+ Amp) designed for the
bus fleets had the AC terminals brought out to the case.

Common practice was to grab a couple of AC terminals and install a
single phase, half wave bridge across the AC which was then
connected to a DC relay with the contacts of this relay wired into the
field circuit.

SFWIW, field current was limited to 5 amps back then.

When the engine was starting, the field relay was open which basically
eliminated any alternator belt loading on the engine.

There is enough residual magnetism in the rotor & stator that when the
engine has started and up to speed, sufficient voltage is generated
to excite the relay and start charging the system.
-------------------------------------------------------
"Flying Pig" wrote:


But we DO have belt dust, a bit. Never had a squealer, though; our
alternator's only 70A and as far as I can tell, it's never
challenged the belt, particularly.
----------------------------------------------------------
You have a problem. Sooner or later it is going to bite you.

The better but not necessarily the easiest solution is to move to a
dual
belt system.

Since the alternator is not your primary recharging device, you might
consider increasing the alternator sheave diameter and staying with
one belt.

You WILL reduce the output, but by how much can only be determined
from an output curve.

Lew