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I need a new alternator [message #88946] Thu, 17 June 2010 07:39 Go to next message
Keith V is currently offline  Keith V   United States
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Registered: March 2008
Location: Mounds View,MN
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Senior Member
My alternator light came on, so I pull the thing, open it up and test the diodes, they look OK.

After reassembling it I spin it and something is hitting. On the rotor there is a thin metal piece that looks like an elongated diamond, this goes over the edge of the rotor.
I popped it back in place and it works again.

I don't know if that was the problem or not, but I don't rust this alternator.


So the question...
What is special about this huge alternator? does it put out more current? No one around here knows what it is as there are no part numbers on it and 1975 GMC motorhome isn't in their computer.

Where do I get a suitable replacement locally?
( yes I know Jim has alts, but the pics look like the small ones..)


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: I need a new alternator [message #88948 is a reply to message #88946] Thu, 17 June 2010 07:50 Go to previous messageGo to next message
John Sharpe is currently offline  John Sharpe   United States
Messages: 489
Registered: February 2006
Location: Texas
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Senior Member
Quote:

What is special about this huge alternator? does it put out more current? No one around here knows what it is as there are no part numbers on it and 1975 GMC motorhome isn't in their computer.

Where do I get a suitable replacement locally?


Keith, Join GMCMI and you get a parts list. That said, they used these on big Caddy limo's. Go to Autozone, Advanced, O'reilly's etc and ask for an alternator for a 1975 Cadillac Limo. A good counter jockey should be able to come up with one.


John Sharpe
Humble,TX
'78 Eleganza TBI
'89 Spectrum 2000 MPI V-10
'40 Ford Panel Delivery TPI
johnasharpe@gmail.com
Re: I need a new alternator [message #88950 is a reply to message #88948] Thu, 17 June 2010 07:54 Go to previous messageGo to next message
peter lyons is currently offline  peter lyons   United States
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Registered: June 2007
Location: New Albany, Indiana
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Junior Member
If i'm not mistaken, you'll need the 80 amp version. We got ours from NAPA a couple of years ago. Just tell them it's a 76 Olds Toronado.

Pete Lyons
76 Eleganza II
Re: [GMCnet] I need a new alternator [message #88955 is a reply to message #88946] Thu, 17 June 2010 08:10 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
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Senior Member
>
> Where do I get a suitable replacement locally?
>

find a local re-builder,

DO NOT BUY ONE FROM NAPA

or the other auto part shops. we have had folks get 3 bad ones in a row.
They just replace the dead parts but everything inside the alternator needs
to be replaced ( especially the stator windings- which they never replace)

so take your alternator to a local re-builder, tell him to replace
everything inside, windings, bearings, electronics , and test the final
rebuild.

size is not critical, 80 amps will be fine , you can go up to over 100 but
your batteries will not charge any faster because they will only take the
current they want to take, having another 100 amps available, will not
matter ;>)

gene

or the the other

--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: I need a new alternator [message #88959 is a reply to message #88948] Thu, 17 June 2010 08:26 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
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Senior Member
John Sharpe wrote on Thu, 17 June 2010 07:50

Quote:


Where do I get a suitable replacement locally?


Keith, Join GMCMI and you get a parts list. That said, they used these on big Caddy limo's. Go to Autozone, Advanced, O'reilly's etc and ask for an alternator for a 1975 Cadillac Limo. A good counter jockey should be able to come up with one.


You know I am a member of GMCMI, but my GMC is a Royale (i.e. Transmode), that was redone in 2000 and has few actual GMC parts left, everything seems to be special.

Gene, I've heard you say that before Wink
I kind of want a new one since this one has that loose part inside, but I suppose a rebuilder and handle that


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] I need a new alternator [message #88963 is a reply to message #88959] Thu, 17 June 2010 08:29 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
yup, yup

and you know where he lives, if there is any problem ;>)

gene



On Thu, Jun 17, 2010 at 6:26 AM, Keith V <my427v8@hotmail.com> wrote:

>
>
> John Sharpe wrote on Thu, 17 June 2010 07:50
> > Quote:
> > > Where do I get a suitable replacement locally?
> >
> >
> > Keith, Join GMCMI and you get a parts list. That said, they used these
> on big Caddy limo's. Go to Autozone, Advanced, O'reilly's etc and ask for
> an alternator for a 1975 Cadillac Limo. A good counter jockey should be
> able to come up with one.
>
>
> You know I am a member of GMCMI, but my GMC is a Royale (i.e. Transmode),
> that was redone in 2000 and has few actual GMC parts left, everything seems
> to be special.
>
> Gene, I've heard you say that before ;)
> I kind of want a new one since this one has that loose part inside, but I
> suppose a rebuilder and handle that
> --
> Keith
> 69 Vette
> 29 Dodge
> 75 Royale GMC
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] I need a new alternator [message #88964 is a reply to message #88946] Thu, 17 June 2010 08:39 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Registered: March 2004
Location: Americus, GA
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Senior Member
Keith,

You may want to review this web site and consider installing a more modern
alternator; the CS-130 and CS-144 are reportedly direct replacements for our
SI series alternators. I haven't done such a swap; I jumped the CS-130 and
put a CS-130D on the Cad500 I recently installed. That's a 100A unit <1/2
the size of the 21SI, but it's not a direct replacement.

http://oljeep.com/gw/alt/edge_Alternator_Theory.html#Section_3

Ken H.
Americus, GA
'76 X-Birchaven
www.gmcwipersetc.com


On Thu, Jun 17, 2010 at 8:39 AM, Keith V <my427v8@hotmail.com> wrote:

> My alternator light came on, so I pull the thing, open it up and test the
> diodes, they look OK.
> ...
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] I need a new alternator [message #88969 is a reply to message #88948] Thu, 17 June 2010 09:34 Go to previous messageGo to next message
Jim Bounds is currently offline  Jim Bounds   United States
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Registered: January 2004
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Senior Member
The advice on not using a rebuilt alternator is good-- they do not replace everything.  A local builder will at least do things because you specify.  We use Delco remanufactured only.  There are supposed to replace most everything inside, the Delco number is 321-136.  This is what we do,

Jim Bounds
-----------------------



----- Original Message ----
From: John Sharpe <johnasharpe@earthlink.net>
To: gmclist@temp.gmcnet.org
Sent: Thu, June 17, 2010 8:50:59 AM
Subject: Re: [GMCnet] I need a new alternator



Quote:
> What is special about this huge alternator? does it put out more current? No one around here knows what it is as there are no part numbers on it and 1975 GMC motorhome isn't in their computer.
>
> Where do I get a suitable replacement locally?


Keith,  Join GMCMI and you get a parts list.  That said, they used these on big Caddy limo's.  Go to Autozone, Advanced, O'reilly's etc and ask for an alternator for a 1975 Cadillac Limo.  A good counter jockey should be able to come up with one.
--
John Sharpe
Humble,TX
'40 Ford Deluxe TBI
'78 Eleganza TBI
'78 Royale TBI
mailto:johnasharpe@earthlink.net
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist




_______________________________________________
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Re: I need a new alternator [message #88982 is a reply to message #88946] Thu, 17 June 2010 10:55 Go to previous messageGo to next message
Surbo is currently offline  Surbo   United States
Messages: 213
Registered: February 2004
Karma: 0
Senior Member
Keith V wrote on Thu, 17 June 2010 07:39

My alternator light came on, so I pull the thing, open it up and test the diodes, they look OK.

After reassembling it I spin it and something is hitting. On the rotor there is a thin metal piece that looks like an elongated diamond, this goes over the edge of the rotor.
I popped it back in place and it works again.

I don't know if that was the problem or not, but I don't rust this alternator.


So the question...
What is special about this huge alternator? does it put out more current? No one around here knows what it is as there are no part numbers on it and 1975 GMC motorhome isn't in their computer.

Where do I get a suitable replacement locally?
( yes I know Jim has alts, but the pics look like the small ones..)


Keith;

Wilson markets rebuilt alts & starters, as good as your going to find. Used many of their products in the ag business. They have the 90-01-3091, which is 100 amp, also sold by NAPA with the #13-4095. Wilson has the 90-01-3070 which is 80 amp, NAPA # is 13-4022.

Wilson also has the parts for sale if you or someone you know wants to rebuid.

JimB has the Delco rebuilds, 321-136 which is a 100 amp, the Delco reman 80 amp is # 321-391.

Take a look at Wilson's excellent site;

https://ws1.wilsonautoelectric.com/ec03/index.php

If you are running EFI, watch the cheapies...they give out a lot of EMI and RFI and it will give the EFI fits!

Bob D in SESD
Re: I need a new alternator [message #89124 is a reply to message #88946] Fri, 18 June 2010 13:15 Go to previous message
Duce Apocalypse is currently offline  Duce Apocalypse   Canada
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Registered: May 2009
Location: Los angeles
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Senior Member

Well I used a mens mall $20 special off an early 80s caddy. Its run fine for about 2 years now. I will eventually upgrade to a nice new unit from PAperformance.com their units are 100% new and warrented for life but they are not cheap....

73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
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