From: John De Armond
Subject: Re: Measuring Alternator Output.
Date: Fri, 16 Jun 2000 20:27:15 EDT
Eric Roellig wrote:
> Neon John wrote:
> One of the guys suggested my 130amp alternator should be limited to
> about 100amp continuous. He also said he used to work on buses with 350
> amp alternators. They pumped engine oil through them to keep them cooled
I probably wouldn't go that high until I instrumented the internal
diode heat sinks and saw how hot they're getting.
I was helping my friend who has the electric motor shop one
afternoon awhile back when we got one of those huge bus alternators
in for overhaul along with a couple of 24 volt 1 hp fans for the AC
condensers! Had to use the overhead crane to get that puppy up on
the bench. I was impressed.
> > > An Auto Zone manager warned me that the alternator lifetime warranty
> > > will not be honored much longer at this rate!!
> > >
> > > I would like to put an ammeter on the van after the alternator to see
> > > how hard I am pulling it. Anyone know where I can get a meter to handle
> > > 130amps or so? Best I (or my mechanic) can find is a +-60amp meter.
> > > Idealy, I would like to find one that uses a shunt so I don't have to
> > > run a high current wire all over the place.
> > Probably the cheapest device that you can get is a clamp-on DC
> > ammeter. Cost is in the $100-150 range. Shunts are available - I
> > have several - but are a pain to use as test instruments because
> > they must be wired in.
> I'm not worried about wiring in. I'm interested in permanent
OK, these guys will sell you a shunt at full retail plus:
They resell the Deltec shunt. This is a common industrial shunt so
you probably can beat the price by looking around. Grainger
(http://www.grainger.com/cgi-bin/ngs?4974164YXkk1282kk1T995) has 'em
too. Looks like $45 for a typical one.
The shunt will give you a millivolt per amp typically. You can get
a (expensive) meter calibrated in amps or you can adapt other
meters. I have some bare chassis digital panel meters that I
bought, I believe, from Digikey (http://www.digikey.com) for either
$10 or $20. These meters display 0 - 19.99 millivolts to 0 - 1999.9
millivolts depending on the jumper setting. The only problem with
these meters is that it must have an independent power supply (no
common ground). It'll run for weeks on a 9 volt battery so that's
no big deal. Digikey sells little DC-DC modules that will let you
power the meter from 12 volts.
Of course, you could just read the shunt with a cheap DVM.
> > > Any better ideas?
> > Well, the cheap and dirty way to address the problem is to insert
> > some resistance in the trailer wiring to limit the current available
> > for charging.
> I'll consider it for the short term.
Adding a little resistance to a hard voltage source (your
alternator) makes it approximate a constant current charging source
and that's not at all bad. Might end up being a long term solution
if you drive enough to still charge the batteries.
> > A better solution is the one I did on my rig, fitting
> > a heavy duty alternator. I couldn't get a semi alternator to fit so
> > I selected the next best thing, a 160 amp alternator from a late
> > model Cadillac. This particular alternator is designed to supply a
> > substantial portion of that 160 amps full time because that car is
> > such a power hog. The thin film defrost coating on the windows
> > draws something like 60 amps all by itself.
> Also on my list of possibilities.
> > A better solution if you have the room is to fit a semi-truck
> > alternator. A 100 amp unit would probably fit with only some
> > bracket modification and would carry the freight all day long.
> My alternator bolts right on to the block. I'd have to see what could
> be done there...
Oh. One of those. Bummer. Fabricating a bracket is always an
option. You might also want to check with what is available on
later model Fords. I looked at a camping neighbor's brandy new 2000
model F350 diesel a few weeks ago. It came from the factory with
two LARGE alternators. One mounted up top directly to the engine
block in the normal position while the other one sat very low on
the block on brackets. You might be able to adapt some of this
hardware to your engine.
> Thanks for the suggestions John.
YOu're welcome. Oh, forgot to add before. Never, ever, ever, ever
except in an emergency buy a rebuilt device from Autozone. Or
anyone for that matter. There was an article a year or so ago in
Forbes about how the stock speculators had invaded the staid
rebuilding industry and trashed it. The current products reflect
that fact. Your friendly local auto parts store (including
Autozone) can order you the new part. Expensive but worth it.
Here's an example that happened just yesterday. I'm presently
converting the vehicle AC on my MH from the old shake-o-matic York
compressor to a modern Sanden rotary piston unit. This is a
WONDERFUL conversion that I've done several times before. Anyway, I
was at my friend's auto parts store showing which new Sanden (SD-510
in this case) compressor I wanted him to order for me. He pushed me
to take a rebuilt one. I told him that I'd bet him a steak dinner
that I could grab a random 4-seasons rebuilt compressor off his
shelf and show him something wrong with it. he took the bet,
natch. I grabbed a Sanden, opened the box, observed the nice
overhaul-via-paint-can job and unscrewed the protective cap from the
discharge port. I poked a rag a little down the port and got....
Sand and soot.
They had simply sandblasted the outside of the thing, painted it and
shipped it out. I've seen this on the last two units I've looked at
so this was a loaded bet. I get my steak tonight :-)
If a rebuilt part will get me off the side of the road, I'll take
it. But ordinarily I want new. My labor's worth too much to have
to change out parts multiple times.
From: John De Armond
Subject: Re: Rebuilt parts (was- blah blah.Re: BF (not BS) again
Date: Mon, 26 Aug 2002 03:19:49 -0400
On Sun, 25 Aug 2002 12:51:59 -0400, Chris Bryant <BryantRVfirstname.lastname@example.org>
> Yeah- I get a few automotive trade magazines, and recall
>seeing an article about how it just isn't worth it to rebuild anything
>any more- the large rebuilding shops do it on an assembly line, with
>all of the tools and parts at hand.
> Rebuilt front calipers are around $30 for my truck- a rebuilt
>starter (with lifetime warranty) was $40. A local shop just couldn't
>compete with prices like that.
After a hard lesson learned at the School of Hard Knocks, I will NOT buy reman
car parts. I still do a little wrenching on the side and I've been burned far
too often. Recent example: I recently replaced a Sanden compressor for a
customer. Both the rebuilt unit he brought along from Autozombie and the one
I had him go get from NAPA had sand blasting sand in the ports under the seal
caps. A brand new unit was only about $100 more than the reman and it was
pristine, as would be expected.
Example 2: I needed a new alternator for my 91 Caprice. This uses the new
style disposable alternator with all welded connections so I decided to try a
Delco brand reman from NAPA, supposedly the best of the remans. Spun it up on
my alternator test bench and nada, no output. Took it apart and found one slip
ring to be devoid of metal. Apparently the yokel who turned it just machined
all the copper off. Of course the assembler used the obviously defective
part. I also found sandblasting grit in the rear bearing housing and found
the brushes to be the worn-out ones that were in the defective unit. Again, a
new alternator was about $100 more than the reman unit and it was actually
Example 3: The stock alternator for my MH is no longer available new. I
looked at the selection of remans on the shelves of my friendly local NAPA
store. They all looked like victims of sand blasting gone bad. I took my old
unit over to the local automotive electric shop (Red Hot batteries, for folks
near to cleveland) and had it rebuilt. Somehow he manages to do it without
sandblasting the damned thing. New bearings, new brushes and a new rectifier
- $25. Spun up and tested to capacity on HIS alternator test bench before I
took possession of it.
Note that I don't want this to sound like a slam of NAPA. I think NAPA still
stocks the best parts of any of the aftermarket stores. It's just that since
Wall Street moved into the reman business, the focus has shifted completely
away from doing a quality job and to short term profits for the stockholders.
From: John De Armond
Subject: Re: Hydraulic pump hell.
Date: Wed, 01 Oct 2003 13:43:06 -0400
the problem almost surely is that he is using remanufactured pumps. Reman
parts are trash these days. Spend the extra money and buy a NEW pump,
preferably from the OEM (ford, chevy, etc). There are many dealerships that
sell parts at a discount online.
If you don't want to pay that price (I'll guestimate about $300) then at least
get an aftermarket NEW (NOT reman) pump. NAPA carries a good line of 3rd
party manufactured new parts. Expect to pay $150-200.
Your mechanic is probably using reman parts to save you money. he knows that
most people will beat him up on the price of new parts. Either get the
correct part yourself or tell him that you want a new OEM part and be prepared
to pay the price, including a markup for his time.
In the future do NOT replace a part with nothing more than a leak. Find a
specialty shop that can rebuild it. Unlike the Wall Street-infested major
remanufacturers, a specialty shop will not mix and match parts, disassemble
hundreds of units and toss all the parts in a big bin, carelessly sandblast
precision parts and other evils. The specialty shop will replace what is worn
on your unit and give it back to you. For a fraction of the cost of a reman
On Wed, 01 Oct 2003 06:31:59 GMT, Dave J. <email@example.com> wrote:
>My new/used RV is still in the shop after over two weeks. It was
>supposed to be preventative maintenance but now I'm waiting for them
>to put replacement power steering pump # 4 in. They tried 3 other
>pumps already...all brand new. Each one seems to have had a different
>problem but I can't remember what they all were. The latest problem
>with pump # 3 was a new whining sound. It took them 3 days to find
>where the sound was coming from and against all odds, it turns out to
>be the latest pump.
>The original pump was just leaking a little. They said it would keep
>working for a while but I would have to keep checking the fluid level
>more often. So I decided to allow them to put a new power steering
>pump in because of the slight leak.
>The place is called "Superior Automotive" in Morgan Hill, Ca. next
>door to Alpine Rec. Does anyone have any bad experiences with this
>shop like me? I didn't want to go into the other issues with the shop,
>but I'm frustrated for more than one reason and it has a lot to do
>with broken promises and unrealistic time predictions that always turn
>out to be missed deadlines. And the work seems to be slowing down now
>that they are frustrated with the repeated problems too.
>Is this a very extraordinary piece of bad luck or could the shop be
>installing the wrong part?
From: John De Armond
Subject: Re: Preemitive strike on MH?
Date: Mon, 18 Apr 2005 20:30:57 -0400
"Frank" <firstname.lastname@example.org> wrote in message
>I bought a rebuilt alternator from Napa with 2
> year warranty, and just finished putting it on.
Frank, I encourage you in the strongest terms possible to take that
rebuilt part back and replace it with a new one. NAPA also sells new
parts. If you want to see why I so strongly recommend that, take a
look at my web site under RV electrical (I think, sorry on dialup and
can't look for sure). There you'll find the dissection of a NAPA
rebuilt alternator in all its horrible glory. NAPA is one of the
better rebuilders too.
A few years ago the wall street types invaded the reman business.
They bought up and consolidated many small, reputable reman houses.
The focus moved from quality to profits. Now, the first thing that
happens to, say, an alternator is that it is disassembled and the
parts thrown in bins of like parts. End bells all get glommed
together. Next is the sand blaster. As you can see from my photos,
everything gets blasted. Then random parts get assembled to make
"new" alternators. No matching of parts, no select fitting, none of
the stuff that the OEM does. If it makes voltage during a brief
spin-up, it gets shipped.
I have literally shaken sand out of reman accessories fresh out of the
box. This includes shaking sand out of the freon ports on more than
one rebuilt AC compressor.
These outfits can afford to give you a long warranty because there is
so much profit in the way they reman nowadays. Problem is, the
warranty doesn't cover the removal and reinstallation, where all the
cost and aggrivation to you is.
A new part will cost maybe twice a reman but it's more than worth it.
The last alternator I bought was for my Caprice and cost about $85
from NAPA. The reman was about $40. It's worth the extra money not
to have to pull the thing again in a few months.
From: John De Armond
Subject: Re: Air Filter Test and Data
Date: Tue, 09 May 2006 22:38:24 -0400
On Mon, 8 May 2006 13:04:15 -0500, "Tom Shaw" <email@example.com>
>I mentioned a while ago that AC Spark Plug, now AC Delco, was way ahead of
>the game years ago when they made calibrated dirt to check out their
>filters...they even sold it in different grades to other filter makers for
>their testing. Nuff said.
I really like Delco products. I've had better luck with AC plugs than
any other brand except NGK and NGK doesn't have the variety.
I have become disturbed lately to see Delco whoring their brand name
to so really bottom-of-the-barrel reman parts. Alternator stators
with the insulation sand-blasted off the windings. Sand shaking out
of a port on an AC compressor. More than one of those. After the
sand shook out of the port of Delco-brand reman AC compressor I'd
accepted after the new version was back-ordered, my friend who owns
the store and I did a sampling of compressors on the shelf. All were
I don't understand why a company works so hard to build a brand name,
only to spoil it with these kinds of antics.
From: John De Armond
Subject: Re: NO BRAKES !!!!
Date: Tue, 16 Sep 2008 04:16:21 -0400
On Sun, 14 Sep 2008 08:35:42 -0400, Lee <firstname.lastname@example.org> wrote:
>Hi LZ and JC
>Many thanks for your replies. Will give it a check but I have about
>zero mechanical abilities so will let the "experts" check it out. Hey
>this is what the NG is all about right? (grin) BTW just had a 30k
>inspection on the MH and everything checked out OK supposedly.
Not one chance in a million that they did anything other than pop the MC lid
and look at the fluid level.
You know, you might consider doing like I do. I carry a spare MC, alternator,
starter motor, ignition module, hoses, water pump and a few other things. Even
if you can't change them yourself (I'm approaching that point), they'd be
available for some other mechanic or helpful RV park neighbor. If you end up
at a small town garage or a truck shop like TA Travel Centers have, you can
supply the part and not get ripped off with on-the-road parts prices.
Even my trucking company equipped my tractor with a selection of spare parts,
though we weren't allowed to work on the rigs ourselves. They were available
for the garage mechanic. I blew a turbocharger boot once. I had the part but
I made the mistake of messaging in to ask permission. The result was that I
got to sit on the side of the road for 2 hours waiting on the roadside service
truck to show up. Not getting paid, of course. I could have swapped the boot
in oh, 10 minutes. Lesson learned!
Over the years I've owned my rig, I've changed the alternator 3 times (before
I replaced it with a more suitably sized unit), the water pump once and the
starter motor once plus a number of small things like marker lights and a
On one occasion in my Fury I got burned by not following my own advice. I
blew a radiator hose in a little cross-roads about 40 miles south of Atlanta.
The mechanic at the town's lone shop said that he'd stay over and replace the
hose if I could find one, as the town's parts store was closed.
After about an hour on the cellphone, I found a hose in Atlanta and hired a
courier to run it down to me. The hose cost about $20. Getting it there and
installed was about $200. After that I put a complete set of hoses AND a tool
box in the car. I paid the stupid tax that day.
Oh, one other tip. Do NOT let them use remanufactured parts. Remans used to
be a good deal but about 15 years ago the Wall Street sharks got involved in
the industry, did a lot of consolidation and drove the small regional
remanufacturers out of business. What now comes out of the box is junk. What
constitutes reman nowadays is sandblasting all the parts, screwing up machined
surfaces in the process. Here's an example of a reman alternator from
Another example. Right before I hit the road in the truck, I replaced the AC
pump on a customer's car. He was too cheap to let me buy new so we got a
reman from NAPA. I pulled the sealing plugs out of the refrigerant ports and
shook out sandblasting sand. He got a replacement from NAPA. I pulled the
plugs and produced more sand. He finally listened, bought a new compressor
from NAPA, I installed it and everything was fine.
The reman unit cost about $60 and the new one about $125. If I'd been a
typical parts-changer and blindly installed the reman unit, the labor to R&R
it in a couple of weeks after it failed again would have eaten up the price
difference. The NAPA "lifetime warranty" would have gotten him another sand
dispenser (ahem) but it would not pay my labor.
BTW, when I say "new", I don't mean go to the dealer and pay their exorbitant
prices. I mean a newly manufactured part from the car parts store. They all
have 'em, even the big box chains, though you do have to ask for them. Even
with new parts, you have to pay attention. There are any number of
replacement parts cloners, usually in Mexico or China, who copy parts. What
you want is a part from the same company that made the OEM part. If it's a
Delco alternator then make sure the new part is also Delco.
Ford's bad about using multiple manufacturers for components so sometimes a
little research is necessary to see if the parts store's "new" part is really
from an OEM supplier. GM's not nearly so bad in that regard.