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Generator light on ... alternator is charging... [message #312821] Sun, 05 February 2017 12:24 Go to next message
amdgmcman is currently offline  amdgmcman   Canada
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Registered: April 2007
Location: Long Beach, CA
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Member
Greetings,

The 100 amp alternator on my 78 Royale is putting out 13+v, and yet the GEN light on the dash is on. The belt is tight and the connections are clean. Has anyone had this problem? Is there a relay or??? that might be faulty ... and Where might it be located? Any help would be greatly appreciated of course.

Thanks,


AMDGMCMan
Alan M DeLuccio
78 Royale with
Coachmen,Center Kitchen Floorplan
09 Harley Davidson Street Glide
65 Corvair Monza Convertible
96 RAV4 2 door Manual 4WD
Long Beach, CA
Re: Generator light on ... alternator is charging... [message #312823 is a reply to message #312821] Sun, 05 February 2017 13:36 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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When you say 'on,' do you mean bright or dim amount of light? Different answers.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Generator light on ... alternator is charging... [message #312826 is a reply to message #312823] Sun, 05 February 2017 13:44 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
Do you have an APC .?

Read my tag line

On Sun, Feb 5, 2017 at 11:37 AM Thomas Phipps wrote:

> When you say 'on,' do you mean bright or dim amount of light? Different
> answers.
> Tom, MS II
> --
> 1975 GMC Avion
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
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] Generator light on ... alternator is charging...you may not have an. APC ?read my tag line [message #312827 is a reply to message #312823] Sun, 05 February 2017 13:41 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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On Sun, Feb 5, 2017 at 11:37 AM Thomas Phipps wrote:

> When you say 'on,' do you mean bright or dim amount of light? Different
> answers.
> Tom, MS II
> --
> 1975 GMC Avion
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
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: Generator light on ... alternator is charging... [message #312829 is a reply to message #312821] Sun, 05 February 2017 13:56 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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amdgmcman wrote on Sun, 05 February 2017 12:24
Greetings,
The 100 amp alternator on my 78 Royale is putting out 13+v, and yet the GEN light on the dash is on. The belt is tight and the connections are clean. Has anyone had this problem? Is there a relay or??? that might be faulty ... and Where might it be located? Any help would be greatly appreciated of course.

Thanks,
If not already done, get and install an APC from Mr. ERF. Then, if that doesn't fix it, post back here.
http://gmcmotorhome.info/APC.html
Re: [GMCnet] Generator light on ... alternator is charging... [message #312830 is a reply to message #312826] Sun, 05 February 2017 13:54 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
On Sun, Feb 5, 2017 at 11:44 AM gene Fisher wrote:

>
>
> Do you have an APC .?
>
> Read my tag line
>

Or read here

http://www.gmcmotorhome.info/engine.html#alternator
>



> On Sun, Feb 5, 2017 at 11:37 AM Thomas Phipps wrote:
>
> When you say 'on,' do you mean bright or dim amount of light? Different
> answers.
> Tom, MS II
> --
> 1975 GMC Avion
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> --
> 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
>
--
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
_______________________________________________
GMCnet mailing list
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Re: Generator light on ... alternator is charging... [message #312831 is a reply to message #312821] Sun, 05 February 2017 14:16 Go to previous messageGo to next message
amdgmcman is currently offline  amdgmcman   Canada
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Location: Long Beach, CA
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I have/had been using an APC. The light came on while it was installed. I removed it ... tightened and cleaned everything, but when removing the APC the tab/clip on the connector on the side that connects to the alt broke off, so I have not reinstalled it.

AMDGMCMan
Alan M DeLuccio
78 Royale with
Coachmen,Center Kitchen Floorplan
09 Harley Davidson Street Glide
65 Corvair Monza Convertible
96 RAV4 2 door Manual 4WD
Long Beach, CA
Re: [GMCnet] Generator light on ... alternator is charging... [message #312832 is a reply to message #312831] Sun, 05 February 2017 14:22 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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On Sun, Feb 5, 2017 at 12:17 PM Alan M DeLuccio
wrote:

> I have/had been using an APC. The light came on while it was installed. I
> removed it ... tightened and cleaned everything, but when removing the APC
> the tab/clip on the connector on the side that connects to the alt broke
> off, so I have not reinstalled it.
> --
> AMDGMCMan
> Alan M DeLuccio
> 78 Royale with
> Coachmen,Center Kitchen Floorplan
> 09 Harley Davidson Street Glide
> 65 Corvair Monza Convertible
> 96 RAV4 2 door Manual 4WD
> Long Beach, CA
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
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
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
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Re: Generator light on ... alternator is charging... [message #312833 is a reply to message #312831] Sun, 05 February 2017 14:30 Go to previous messageGo to next message
amdgmcman is currently offline  amdgmcman   Canada
Messages: 76
Registered: April 2007
Location: Long Beach, CA
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The steering boot(s) also need replacement. There are 2 types offered at Applied. The Al Ferrara's Steering Boot Kit and the GM16-STBOOT. Does anyone have experience with these 2 kits? Is one an easier install than the other. I changed mine out about 10 years ago and it was a pain.

AMDGMCMan
Alan M DeLuccio
78 Royale with
Coachmen,Center Kitchen Floorplan
09 Harley Davidson Street Glide
65 Corvair Monza Convertible
96 RAV4 2 door Manual 4WD
Long Beach, CA
Re: Generator light on ... alternator is charging... [message #312835 is a reply to message #312833] Sun, 05 February 2017 14:34 Go to previous messageGo to next message
amdgmcman is currently offline  amdgmcman   Canada
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Location: Long Beach, CA
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Member
The GEN light is DIM ...not Bright

AMDGMCMan
Alan M DeLuccio
78 Royale with
Coachmen,Center Kitchen Floorplan
09 Harley Davidson Street Glide
65 Corvair Monza Convertible
96 RAV4 2 door Manual 4WD
Long Beach, CA
Re: Generator light on ... alternator is charging... [message #312839 is a reply to message #312821] Sun, 05 February 2017 15:47 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Location: Hebron, Indiana
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Senior Member
Output of the alternator should be around 14.7 volts if you are reading it at the alternator or at the center post of the isolator. If read after the isolator it should be 13.8 to 14.2 vDC.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Generator light on ... alternator is charging... [message #312841 is a reply to message #312821] Sun, 05 February 2017 16:04 Go to previous messageGo to next message
bwevers is currently offline  bwevers   United States
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http://www.gmcmotorhome.info/engine.html#alternator
http://www.gmcmotorhome.info/engine.html#alternator


Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose
Re: Generator light on ... alternator is charging... [message #312914 is a reply to message #312821] Wed, 08 February 2017 09:43 Go to previous messageGo to next message
Tony Cook is currently offline  Tony Cook   United States
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Sign of your alternator going out. My indicator was glowing dim even with the APC cable installed . Alternator finaly died R&R'd and no more glow.

Tony Cook 77' Kingsley ' SuperSession 77 ' Torrance Beach,CA
Re: Generator light on ... alternator is charging... [message #312930 is a reply to message #312835] Wed, 08 February 2017 13:08 Go to previous messageGo to next message
pjburt is currently offline  pjburt   United States
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amdgmcman wrote on Sun, 05 February 2017 12:34
The GEN light is DIM ...not Bright


A quick and easy check before you get too involved:
If you read down low enough on the gmcmotorhome.info links people have posted, you'll see a blurb about checking the dash lights fuse on the panel in the glove box. Mine was blown and replacing it was the cure for me when my light did that.


Jerry Burt Fresno, CA.
73 Gmc 26' Canyon Lands
Members: FMCA - GMCMI - GMCWS
A truly happy person is one who can enjoy the scenery on a detour.
Re: Generator light on ... alternator is charging... [message #315092 is a reply to message #312930] Fri, 24 March 2017 22:59 Go to previous messageGo to next message
amdgmcman is currently offline  amdgmcman   Canada
Messages: 76
Registered: April 2007
Location: Long Beach, CA
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Member
Greetings,

Can an APC go bad? I have had one installed on my GMC for quite a few years and just recently the GEN light has come on. Dim ... but on. It is a 78, and I read that GM solved a problem in later models that occurred on earlier models that caused the GEN light to glow dim.The GEN is putting out voltage ... approx 13 volts, so maybe the APC is bad? I had an 100 amp Alternator installed by Miguel at MGM in 2014, so I'm hoping it is not bad.

Comments and suggestions appreciated.

Thanks,


AMDGMCMan
Alan M DeLuccio
78 Royale with
Coachmen,Center Kitchen Floorplan
09 Harley Davidson Street Glide
65 Corvair Monza Convertible
96 RAV4 2 door Manual 4WD
Long Beach, CA
Re: [GMCnet] Generator light on ... alternator is charging... [message #315095 is a reply to message #315092] Sat, 25 March 2017 08:01 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
Your earlier post said you removed it
Barton told you the alternato volts should be 15 volts
Read here
http://www.gmcmotorhome.info/engine.html#alternator

Is prob not the APC


On Fri, Mar 24, 2017 at 9:00 PM Alan M DeLuccio
wrote:

> Greetings,
>
> Can an APC go bad? I have had one installed on my GMC for quite a few
> years and just recently the GEN light has come on. Dim ... but on. It is a
> 78,
> and I read that GM solved a problem in later models that occurred on
> earlier models that caused the GEN light to glow dim.The GEN is putting out
> voltage ... approx 13 volts, so maybe the APC is bad? I had an 100 amp
> Alternator installed by Miguel at MGM in 2014, so I'm hoping it is not bad.
>
> Comments and suggestions appreciated.
>
> Thanks,
> --
> AMDGMCMan
> Alan M DeLuccio
> 78 Royale with
> Coachmen,Center Kitchen Floorplan
> 09 Harley Davidson Street Glide
> 65 Corvair Monza Convertible
> 96 RAV4 2 door Manual 4WD
> Long Beach, CA
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
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
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
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Re: [GMCnet] Generator light on ... alternator is charging... [message #315099 is a reply to message #315095] Sat, 25 March 2017 10:57 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Mr ERFisher wrote on Sat, 25 March 2017 08:01
Your earlier post said you removed it
Barton told you the alternato volts should be 15 volts
Read here
http://www.gmcmotorhome.info/engine.html#alternator

Is prob not the APC
15V sustained is too high, except in sub-zero tempeatures. But 13.6V minimum, generally. More than 14 after a long starter crank.
Re: [GMCnet] Generator light on ... alternator is charging... [message #315100 is a reply to message #315099] Sat, 25 March 2017 10:59 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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A Hamilto wrote on Sat, 25 March 2017 10:57
Mr ERFisher wrote on Sat, 25 March 2017 08:01
Your earlier post said you removed it
Barton told you the alternato volts should be 15 volts
Read here
http://www.gmcmotorhome.info/engine.html#alternator

Is prob not the APC
15V sustained is too high, except in sub-zero tempeatures. But 13.6V minimum, generally. More than 14 after a long starter crank.
Oops. Forgot about the 0.7V drop across the isolator. 15V is not too high.
Re: Generator light on ... alternator is charging... [message #315110 is a reply to message #312821] Sat, 25 March 2017 16:44 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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He needs to tell us how and where he is metering. 13.6-14.2 is ok after the isolator. Where the 13 is metered is important as the sense to the alternator is after the isolator and 13 minus .7 would cause the lamp to glow.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Generator light on ... alternator is charging... [message #315111 is a reply to message #315110] Sat, 25 March 2017 17:17 Go to previous messageGo to previous message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
Here is the bible, do this
http://www.gmcmhphotos.com/photos/data/15/GMC_charging_system_checkout.pdf


On Sat, Mar 25, 2017 at 2:49 PM John R. Lebetski
wrote:

> He needs to tell us how and where he is metering. 13.6-14.2 is ok after
> the isolator. Where the 13 is metered is important as the sense to the
> alternator is after the isolator and 13 minus .7 would cause the lamp to
> glow.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
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--
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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