GM Alternator Rebuild

Ernest,

That is a real good page. The differences between the 10SI and our 27SI are not something most people would notice and the rebuild process is exactly
the same. The big difference with ours is we don't have that resistor that is part of what make it a one-wire type.

Thanks

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
I see you can get a a rebuild kit from this seller for $34.99. https://www.maniacelectricmotors.com/10si-alternator-rebuild-kit.html
I did not do a search for a lower price.

Emery Stora
emerystora

>
> https://www.hemmings.com/stories/2021/07/30/rejuvenating-the-appearance-and-functionality-of-an-original-gm-10si-series-alternator?refer=hccweekly&amp
> ;utm_source=hccweekly&utm_medium=email&utm_campaign=2021-08-04
>
> Nice tutorial on how to rebuild/repair our alternators.
> --
> 1977 Eleganza II
> Ogden NY
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
 
The last GM alternator I had rebuilt just a
month or so ago, was done by a local rebuilder.
New, American made parts included bearings (both ends) Stator and
Rotor, solid state regulator. Large binding post, and duplex connector.
Disassembled, cleaned, stripped threads repaired, and finally a larger
duplex pulley added. Reassembled tested and certified to produce 100 amps
output.
$94.00 in U.S. dollars. Probably better than a brand new one. Quality
has a high price, I guess.
Jim Hupy
Salem, Oregon

On Thu, Aug 5, 2021, 11:37 AM Emery Stora via Gmclist <

> I see you can get a a rebuild kit from this seller for $34.99.
> https://www.maniacelectricmotors.com/10si-alternator-rebuild-kit.html
> I did not do a search for a lower price.
>
> Emery Stora
> emerystora
>
>
>
> > On Aug 4, 2021, at 2:00 PM, Ernest Dankert

> >
> >
> https://www.hemmings.com/stories/2021/07/30/rejuvenating-the-appearance-and-functionality-of-an-original-gm-10si-series-alternator?refer=hccweekly&amp
> > ;utm_source=hccweekly&utm_medium=email&utm_campaign=2021-08-04
> >
> > Nice tutorial on how to rebuild/repair our alternators.
> > --
> > 1977 Eleganza II
> > Ogden NY
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
Note what the voltage "Set Point" is of the replacement voltage regulator module. My experience is common VRs are now running 14.8 volts which to me
in our application is too high. I had to do some searching and came up with a 14.2 volt VR.

The Set point is the voltage the VR wants to see on the voltage sense wire (after the isolator). So you maybe seeing 15.5V at the center terminal of
the isolator.

14.8V might be fine for quick recharging after start-up for personal car that just runs around town... starts drives for 5 ,miles then shut off. But
our coaches typically run for several hours,fuel-up then run for several hours again. So 14.8V, or even 14.5V is high, so I went with 14.2V

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
My thoughts on diodes and regulator is if they are good old Delco parts, leave them alone. Replace the bearings and brushes, and clean all connections
with D5 and reassemble. This has worked for me on GM vehicles.
And now a question for the experts. I understand the brush depressor tool (spray straw or wire provided) for reassembly, but is there a way to
depress the brushes for disassembly so they don’t snap into the gap between the slip rings and crack the brush holder. Seems that happens about
half the time for me.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Yep, if you look carefully at the slip ring brush holders, you will see a
small drilled hole in them. I use round toothpicks or other NON-CONDUCTIVE
similar shaped item. Push the brush back in the holder, which compresses
the spring, insert toothpick, and "Bob's your uncle". Oh yes, don't forget
to pull the toothpicks after you slide the assembly together. Otherwise, no
chargee.
Jim Hupy
Salem, Oregon

On Fri, Aug 6, 2021, 5:33 AM John R. Lebetski
wrote:

> My thoughts on diodes and regulator is if they are good old Delco parts,
> leave them alone. Replace the bearings and brushes, and clean all
> connections
> with D5 and reassemble. This has worked for me on GM vehicles.
> And now a question for the experts. I understand the brush depressor tool
> (spray straw or wire provided) for reassembly, but is there a way to
> depress the brushes for disassembly so they don’t snap into the gap
> between the slip rings and crack the brush holder. Seems that happens about
> half the time for me.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
> Note what the voltage "Set Point" is of the replacement voltage regulator module. My experience is common VRs are now running 14.8 volts which to
> me in our application is too high. I had to do some searching and came up with a 14.2 volt VR.
>
> The Set point is the voltage the VR wants to see on the voltage sense wire (after the isolator). So you maybe seeing 15.5V at the center terminal
> of the isolator.
>
> 14.8V might be fine for quick recharging after start-up for personal car that just runs around town... starts drives for 5 ,miles then shut off.
> But our coaches typically run for several hours,fuel-up then run for several hours again. So 14.8V, or even 14.5V is high, so I went with 14.2V

Bruce,

I steadfastly agree, but I never figured out how to get a regulator with the lower set point. Do you have part numbers or any clue?

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
> My thoughts on diodes and regulator is if they are good old Delco parts, leave them alone. Replace the bearings and brushes, and clean all
> connections with D5 and reassemble. This has worked for me on GM vehicles.
> And now a question for the experts. I understand the brush depressor tool (spray straw or wire provided) for reassembly, but is there a way to
> depress the brushes for disassembly so they don’t snap into the gap between the slip rings and crack the brush holder. Seems that happens about
> half the time for me.

John,

I have had the brushes hang up, but if you can take it apart from the front (sheave end, you can usually do this on a 27) one can tease the rotor out
past the brushes.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
Matt,
I dug around in the Regitar and Trans-pro on-line catalogs until I found the style and voltage set-point I wanted. Then I had to order through an
auto-electric rebuilder.

They kinda looked at me funny when I told them what I wanted as if to say "what's all this voltage and current stuff you speak of anyway??"


--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
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