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Problem #2 bouncing voltmeter. [message #218678] Fri, 16 August 2013 21:17 Go to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Ever since I got the engine combo back together I've noticed that my aftermarket voltmeter is acting a bit weird. It will be showing 13V and about every minute or so it will bounce around between 12-14V. The factory idiot light never flickers. I also installed a Digipanel yesterday and the display on it also shows variable voltage in sync with what is happening on the gauge.

The alternator connections are tight.

I HATE electrical work.

I can pull the alternator and have it checked but if there is a way to check it on the coach, I'd rather. Will it hurt anything if I pull the power feeds off of it and read directly from the output lug with nothing connected to it?

I can live with the bouncing but don't have any idea what it might be a symptom of. I'd hate to be halfway to Branson and smoke some component...

Suggestions welcome.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: Problem #2 bouncing voltmeter. [message #218687 is a reply to message #218678] Fri, 16 August 2013 21:56 Go to previous messageGo to next message
spiffycar is currently offline  spiffycar   United States
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Location: Brook Park ,Ohio
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Are the voltage fluctuations occurring in conjunction with the "chuff-chuff" noise you were referring to in your other post?

Check to see if the bolt that holds the pulley on the alternator shaft has worked itself loose at all.
Also I would check to see if the fan blade on the alternator has been scraping on the alternator case causing the noise you are hearing.

I had a similar situation happen to me on my way back from the Hamilton Rally. The noise started out sounding like a puffing/buffering noise like it was wind related. It continued to keep getting louder and more frequent over the next hundred miles. It eventually started to sound more like a drain snake & I figured it might be the speedo cable was dry.

I finally figured out what it was after the pulley came off!


Paul W L
76 Daytona Beach! ( EX-Palm Beach )
Cleveland,OH
& Current Card Carrying Pull A Part VIP Member
Re: Problem #2 bouncing voltmeter. [message #218690 is a reply to message #218687] Fri, 16 August 2013 22:18 Go to previous messageGo to next message
spiffycar is currently offline  spiffycar   United States
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A follow pic I forgot to add to my previous reply...


http://www.gmcmhphotos.com/photos/miscellaneous-fixes-upgrades-amp-other-stuff/p50475-dsc03107.html


Paul W L
76 Daytona Beach! ( EX-Palm Beach )
Cleveland,OH
& Current Card Carrying Pull A Part VIP Member
Re: Problem #2 bouncing voltmeter. [message #218692 is a reply to message #218678] Fri, 16 August 2013 22:40 Go to previous messageGo to next message
Craig Lechowicz is currently offline  Craig Lechowicz   United States
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An intermittent heavy load can also make the volt meter "flicker". I'm wondering if you have an air leak, and your compressor is turning off and on?

Craig Lechowicz
'77 Kingsley, Waterford, MI
Re: Problem #2 bouncing voltmeter. [message #218694 is a reply to message #218692] Fri, 16 August 2013 23:22 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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My digi has been flickering for a while now. My analog meter does not move. Need to check a few things myself. I am thinking a couple of leads from my battery into the coach and clipping my digital volt ohm meter to them so I can determine if I really have a problem. If nothing there I will back the leads up to the alternator so I can watch it while running down the road.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Problem #2 bouncing voltmeter. [message #218717 is a reply to message #218694] Sat, 17 August 2013 07:52 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Senior Member
be sure your belts are tight and not slipping

http://www.gmcmhphotos.com/photos/data/5950/GMC_BELTS_WILL_NOT_LET_YOU_DOWN.pdf
gene


On Fri, Aug 16, 2013 at 9:22 PM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> My digi has been flickering for a while now. My analog meter does not
> move. Need to check a few things myself. I am thinking a couple of leads
> from my battery into the coach and clipping my digital volt ohm meter to
> them so I can determine if I really have a problem. If nothing there I will
> back the leads up to the alternator so I can watch it while running down
> the road.
> Dan
> --
> Dan & Teri Gregg
> Dexter, Mo.
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List 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: Problem #2 bouncing voltmeter. [message #218722 is a reply to message #218678] Sat, 17 August 2013 08:36 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Registered: March 2007
Location: S.E. Michigan
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Kerry Pinkerton wrote on Fri, 16 August 2013 22:17

Ever since I got the engine combo back together I've noticed that my aftermarket voltmeter is acting a bit weird. It will be showing 13V and about every minute or so it will bounce around between 12-14V. The factory idiot light never flickers. I also installed a Digipanel yesterday and the display on it also shows variable voltage in sync with what is happening on the gauge.

The alternator connections are tight.

I HATE electrical work.

I can pull the alternator and have it checked but if there is a way to check it on the coach, I'd rather. Will it hurt anything if I pull the power feeds off of it and read directly from the output lug with nothing connected to it?

I can live with the bouncing but don't have any idea what it might be a symptom of. I'd hate to be halfway to Branson and smoke some component...

Suggestions welcome.

Kerry,

I kind of hate to tell you this, but that is exactly what I was seeing before the alternator failed totally. It was the regulator going out.

No regular pattern that I could see, but I would look down one time and it would be 12.8, the next 14.2 and the odd 13.6,7,8....

When it held at 12.5 then 4,3,2 I knew I had found the problem.

Matt - Still in Paradise (MI)


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
Re: Problem #2 bouncing voltmeter. [message #218737 is a reply to message #218722] Sat, 17 August 2013 09:20 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Matt Colie wrote on Sat, 17 August 2013 08:36

Kerry Pinkerton wrote on Fri, 16 August 2013 22:17

Ever since I got the engine combo back together I've noticed that my aftermarket voltmeter is acting a bit weird. It will be showing 13V and about every minute or so it will bounce around between 12-14V. The factory idiot light never flickers. I also installed a Digipanel yesterday and the display on it also shows variable voltage in sync with what is happening on the gauge.

The alternator connections are tight.

I HATE electrical work.

I can pull the alternator and have it checked but if there is a way to check it on the coach, I'd rather. Will it hurt anything if I pull the power feeds off of it and read directly from the output lug with nothing connected to it?

I can live with the bouncing but don't have any idea what it might be a symptom of. I'd hate to be halfway to Branson and smoke some component...

Suggestions welcome.


Kerry,

I kind of hate to tell you this, but that is exactly what I was seeing before the alternator failed totally. It was the regulator going out.

No regular pattern that I could see, but I would look down one time and it would be 12.8, the next 14.2 and the odd 13.6,7,8....

When it held at 12.5 then 4,3,2 I knew I had found the problem.

Matt - Still in Paradise (MI)


Still running my 4 yr old autozone alt. (took 3 to get a good one) could very well be my problem, Kerry's too. I carry a locally built one on board. Instead of trying to get autozone to replace I will have my local guy rebuild this one. I figure you have "nailed" my problem. I have the easy tighten unit from Jim K so swapping them out and getting belt tight no big deal, on side of road, LOL.
How bout a few pictures of the UP Matt?
Dan, Yankee born


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Problem #2 bouncing voltmeter. [message #218739 is a reply to message #218737] Sat, 17 August 2013 09:29 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
be sure to have your APC cable on

the alternator is what burns up the wiring

gene



On Sat, Aug 17, 2013 at 7:20 AM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> Matt Colie wrote on Sat, 17 August 2013 08:36
> > Kerry Pinkerton wrote on Fri, 16 August 2013 22:17
> > > Ever since I got the engine combo back together I've noticed that my
> aftermarket voltmeter is acting a bit weird. It will be showing 13V and
> about every minute or so it will bounce around between 12-14V. The factory
> idiot light never flickers. I also installed a Digipanel yesterday and the
> display on it also shows variable voltage in sync with what is happening on
> the gauge.
> > >
> > > The alternator connections are tight.
> > >
> > > I HATE electrical work.
> > >
> > > I can pull the alternator and have it checked but if there is a way to
> check it on the coach, I'd rather. Will it hurt anything if I pull the
> power feeds off of it and read directly from the output lug with nothing
> connected to it?
> > >
> > > I can live with the bouncing but don't have any idea what it might be
> a symptom of. I'd hate to be halfway to Branson and smoke some component...
> > >
> > > Suggestions welcome.
> >
> >
> > Kerry,
> >
> > I kind of hate to tell you this, but that is exactly what I was seeing
> before the alternator failed totally. It was the regulator going out.
> >
> > No regular pattern that I could see, but I would look down one time and
> it would be 12.8, the next 14.2 and the odd 13.6,7,8....
> >
> > When it held at 12.5 then 4,3,2 I knew I had found the problem.
> >
> > Matt - Still in Paradise (MI)
>
>
> Still running my 4 yr old autozone alt. (took 3 to get a good one) could
> very well be my problem, Kerry's too. I carry a locally built one on board.
> Instead of trying to get autozone to replace I will have my local guy
> rebuild this one. I figure you have "nailed" my problem. I have the easy
> tighten unit from Jim K so swapping them out and getting belt tight no big
> deal, on side of road, LOL.
> How bout a few pictures of the UP Matt?
> Dan, Yankee born
>
> --
> Dan & Teri Gregg
> Dexter, Mo.
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List 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] Problem #2 bouncing voltmeter. [message #218741 is a reply to message #218739] Sat, 17 August 2013 09:33 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Mr ERFisher wrote on Sat, 17 August 2013 09:29

be sure to have your APC cable on

the alternator is what burns up the wiring

gene



On Sat, Aug 17, 2013 at 7:20 AM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> Matt Colie wrote on Sat, 17 August 2013 08:36
> > Kerry Pinkerton wrote on Fri, 16 August 2013 22:17
> > > Ever since I got the engine combo back together I've noticed that my
> aftermarket voltmeter is acting a bit weird. It will be showing 13V and
> about every minute or so it will bounce around between 12-14V. The factory
> idiot light never flickers. I also installed a Digipanel yesterday and the
> display on it also shows variable voltage in sync with what is happening on
> the gauge.
> > >
> > > The alternator connections are tight.
> > >
> > > I HATE electrical work.
> > >
> > > I can pull the alternator and have it checked but if there is a way to
> check it on the coach, I'd rather. Will it hurt anything if I pull the
> power feeds off of it and read directly from the output lug with nothing
> connected to it?
> > >
> > > I can live with the bouncing but don't have any idea what it might be
> a symptom of. I'd hate to be halfway to Branson and smoke some component...
> > >
> > > Suggestions welcome.
> >
> >
> > Kerry,
> >
> > I kind of hate to tell you this, but that is exactly what I was seeing
> before the alternator failed totally. It was the regulator going out.
> >
> > No regular pattern that I could see, but I would look down one time and
> it would be 12.8, the next 14.2 and the odd 13.6,7,8....
> >
> > When it held at 12.5 then 4,3,2 I knew I had found the problem.
> >
> > Matt - Still in Paradise (MI)
>
>
> Still running my 4 yr old autozone alt. (took 3 to get a good one) could
> very well be my problem, Kerry's too. I carry a locally built one on board.
> Instead of trying to get autozone to replace I will have my local guy
> rebuild this one. I figure you have "nailed" my problem. I have the easy
> tighten unit from Jim K so swapping them out and getting belt tight no big
> deal, on side of road, LOL.
> How bout a few pictures of the UP Matt?
> Dan, Yankee born
>
> --
> Dan & Teri Gregg
> Dexter, Mo.
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List 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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I have had one since soon after buying our coach.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: Problem #2 bouncing voltmeter. [message #218783 is a reply to message #218678] Sat, 17 August 2013 17:24 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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Kerry Pinkerton wrote on Fri, 16 August 2013 19:17

Ever since I got the engine combo back together I've noticed that my aftermarket voltmeter is acting a bit weird. It will be showing 13V and about every minute or so it will bounce around between 12-14V

I HATE electrical work....

Suggestions welcome.

I hate GM alternators. Ha. I am on my fourth in 34K miles and it is a Whiner. Three of them, including the one I have now flicker the volts constantly. Yes Gene, I have the magic cable in place.

The GM in my '37 Ford flickers like crazy. There are some transistors in the regulator and as Matt said, they go wonky.

I think about changing mine... Again. Can't decide to go with ma an pa, Delco remanufactured in MI, O'Reilys or NAPA. None of the above made me feel warm and fuzzy. (I have a manual turnoff for the air pump and rarely have it on when driving so it is not sudden usage..) I probably will just start for Branson and worry about it if it quits as I won't feel great about anything I bring home to replace it. It has whined quietly for about 9K miles so what is a fellow to do. I installed it in Redding a year ago when it was about 140 in the shade and it whined the second we started to driving again. But we were heading toward the coast so we kept going. Ruth said the other day she thought it was sort of a comforting sound. She's a good girl.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: Problem #2 bouncing voltmeter. [message #218786 is a reply to message #218783] Sat, 17 August 2013 17:50 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Ruth said the other day she thought it was sort of a comforting sound. She's a good girl.[/quote]


Yea George, you also married up. Very Happy
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: Problem #2 bouncing voltmeter. [message #218829 is a reply to message #218786] Sat, 17 August 2013 21:22 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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WD0AFQ wrote on Sat, 17 August 2013 15:50

Ruth said the other day she thought it was sort of a comforting sound. She's a good girl.



Yea George, you also married up. Very Happy
Dan[/quote]


Dan,

I'm pretty sure almost ALL of us did! Rolling Eyes


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Problem #2 bouncing voltmeter. [message #218841 is a reply to message #218678] Sat, 17 August 2013 21:05 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
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Registered: January 2011
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Senior Member
Kerry

It sounds as if your internal voltage regulator in the alternator is going bad. You should take off the alternator and take it in to be tested.

Emery Stora

On Aug 16, 2013, at 8:17 PM, Kerry Pinkerton <Pinkertonk@MCHSI.com> wrote:

>
>
> Ever since I got the engine combo back together I've noticed that my aftermarket voltmeter is acting a bit weird. It will be showing 13V and about every minute or so it will bounce around between 12-14V. The factory idiot light never flickers. I also installed a Digipanel yesterday and the display on it also shows variable voltage in sync with what is happening on the gauge.
>
> The alternator connections are tight.
>
> I HATE electrical work.
>
> I can pull the alternator and have it checked but if there is a way to check it on the coach, I'd rather. Will it hurt anything if I pull the power feeds off of it and read directly from the output lug with nothing connected to it?
>
> I can live with the bouncing but don't have any idea what it might be a symptom of. I'd hate to be halfway to Branson and smoke some component...
>
> Suggestions welcome.
> --
> Kerry Pinkerton
>
> North Alabama, near Huntsville,
>
> 77 Eleganza II, "The Lady", 403CI, also a 76 Eleganza being re-bodied as an Art Deco car hauler
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Re: Problem #2 bouncing voltmeter. [message #218850 is a reply to message #218786] Sun, 18 August 2013 01:39 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
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WD0AFQ wrote on Sat, 17 August 2013 15:50

Ruth said the other day she thought it was sort of a comforting sound. She's a good girl.


Yea George, you also married up. Very Happy
Dan


If I hadn't married Ruth I would have eaten garbage and died by now.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George

[Updated on: Sun, 18 August 2013 01:40]

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Re: [GMCnet] Problem #2 bouncing voltmeter. [message #218997 is a reply to message #218841] Sun, 18 August 2013 20:28 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Emery Stora wrote on Sat, 17 August 2013 22:05

Kerry

It sounds as if your internal voltage regulator in the alternator is going bad. You should take off the alternator and take it in to be tested.

Emery Stora

On Aug 16, 2013, at 8:17 PM, Kerry Pinkerton wrote:

> Ever since I got the engine combo back together I've noticed that my aftermarket voltmeter is acting a bit weird. It will be showing 13V and about every minute or so it will bounce around between 12-14V. The factory idiot light never flickers. I also installed a Digipanel yesterday and the display on it also shows variable voltage in sync with what is happening on the gauge.
>
> The alternator connections are tight.
>
> I HATE electrical work.
>
<SNIP>
>
> Suggestions welcome.
> --
> Kerry Pinkerton

Kerry,

You can hate it all you want, but that regulator (if it is like mine) is going out. That is about all it can be....
When mine was screwing up, it almost tested as in spec on that shops tester (they had a tester specific to Delco regulators), but the guy noticed that it got too hot too fast.

Most of working on and alternator is mechanical. Take the parts out. Put the parts in. Inspect the bearings, slip rings and brushes. If you are smart, you will locate a new regulator for that alternator. That may be a trick as some have external sense (what you want) and some do not. Some are made in China and some in Costa Rica.

You can fix it yourself or you can find the local old guy that actually knows what he is doing.

Good Luck.

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
Re: Problem #2 bouncing voltmeter. [message #218999 is a reply to message #218678] Sun, 18 August 2013 20:32 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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I pulled it out this afternoon. Taking it to the old guy down the road tomorrow.

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: Problem #2 bouncing voltmeter. [message #219479 is a reply to message #218678] Wed, 21 August 2013 16:59 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Got too many threads going with similar subjects. My fault. Regardless, The alternator checked out good by the old man who has been doing this for sixty years.

James Hupy wrote on Wed, 21 August 2013 10:50

Kerry, I am going to go a different direction than everyone else here. You
complained about varying voltage or what I call "spiking" in the alternator
circuit. If that is actually happening, one of those spikes can EASILY kill
the ignition module in your new Paterson distributor. When they fail. they
either go dead alongside the road, never to run again, or they will run
fine until they get nice and warm and then burp, fart, and otherwise mimic
plugged fuel filters or vaporlocking. Electronics do NOT PLAY WELL with
sudden fluctuations in voltage. Ask, Dick Paterson, he will send you some
nightime reading material on this very subject. It has happened to me
several times on different coaches. Frustrating to say the least. Hope you
have solved your problem, but if not, look at the module. ALWAYS carry a
spare one with you, and get that spiking fixed. Something is loose,
corroded, or poorly connected. Shake every connection in the charging
circuit and make everything tight and bright and shiny like a new penny.
Jim Hupy
Salem, OR
78 GMC Royale 403




Great advice Jim. I recently lost a module and had not drawn the connection. I'll start chasing the gremlin.

Let me start by saying I'd rather have a root canal than mess with wiring. But oh well.

I have a combiner installed, I'll pull it off first to isolate everything on the house side. Can I pull fuses to isolate circuits to narrow down the problem?




Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L

[Updated on: Wed, 21 August 2013 17:03]

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Re: [GMCnet] Problem #2 bouncing voltmeter. [message #219485 is a reply to message #219479] Wed, 21 August 2013 17:31 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Senior Member
Kerry, yes pull fuses one at a time.. Test run.. repeat as necessary..I
don't personally use combiners, I think the isolater is enough. I do use a
jumper but it is unhooked until I might need it. I have a very late 78
Royale and it has all the refinements that some of the earlier coaches do
not have. On your coach in the center of the fuse block at the very top
there is a 30 amp circuit breaker. If you have a high current draw in the
EL 2 ride control, that circuit breaker will make and break with a high
current draw that will cause a spike in the charging system. I had a failed
compressor motor in my EL 2 and it did just what I described.
Jim Hupy
Salem, Or
78 GMC Royale 403
On Aug 21, 2013 2:59 PM, "Kerry Pinkerton" <Pinkertonk@mchsi.com> wrote:

>
>
> Got too many threads going with similar subjects. My fault. Regardless,
> The alternator checked out good by the old man who has been doing this for
> sixty years.
>
> James Hupy wrote on Wed, 21 August 2013 10:50
> > Kerry, I am going to go a different direction than everyone else here.
> You
> > complained about varying voltage or what I call "spiking" in the
> alternator
> > circuit. If that is actually happening, one of those spikes can EASILY
> kill
> > the ignition module in your new Paterson distributor. When they fail.
> they
> > either go dead alongside the road, never to run again, or they will run
> > fine until they get nice and warm and then burp, fart, and otherwise
> mimic
> > plugged fuel filters or vaporlocking. Electronics do NOT PLAY WELL with
> > sudden fluctuations in voltage. Ask, Dick Paterson, he will send you some
> > nightime reading material on this very subject. It has happened to me
> > several times on different coaches. Frustrating to say the least. Hope
> you
> > have solved your problem, but if not, look at the module. ALWAYS carry a
> > spare one with you, and get that spiking fixed. Something is loose,
> > corroded, or poorly connected. Shake every connection in the charging
> > circuit and make everything tight and bright and shiny like a new penny.
> > Jim Hupy
> > Salem, OR
> > 78 GMC Royale 403
>
>
>
> Great advice Jim. I recently lost a module and had not drawn the
> connection. I'll start chasing the gremlin.
>
> Let me start by saying I'd rather have a root canal than mess with wiring.
> But oh well.
>
> I have a combiner installed, I'll pull it off first to isolate everything
> on the house side. Can I pull fuses to isolate circuits to narrow down the
> problem.
>
>
>
> --
> Kerry Pinkerton
>
> North Alabama, near Huntsville,
>
> 77 Eleganza II, "The Lady", 403CI, also a 76 Eleganza being re-bodied as
> an Art Deco car hauler
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Re: Problem #2 bouncing voltmeter. [message #219504 is a reply to message #218678] Wed, 21 August 2013 21:01 Go to previous messageGo to previous message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
By the rate at which the voltage is changing, I suspect a bad or cycling combiner. Those combiner things do not switch on immediately but have a long delay to them. I cannot remember if the delay of 30 or 60 seconds.

If you still have an operating isolator then remove that combiner and start trouble shooting your problem that without it. You did did not state where the voltmeter you are looking at is now attached. I'm not sure what voltage at what connection point you wished to monitor with that meter.

Once that combiner is out of the way you can troubleshoot your problem as either the house side, or the engine side, or the alternator. You can monitor the voltage on the center terminal of the isolator and see if the it the voltage fluctuation occurring from the alternator. You will also be able to, monitor the voltage on the upper and lower terminals of the isolator independently to see if the voltage fluctuations are on the loads of the house or engine side.

There is always the possibility of the problem being on the sense wire going to the alternator but I would expect the voltage to go high not low, if the sense lead was acting up.

So disconnect that combiner and start by reading the voltages on all three terminals while it is not failing and again while it is failing. Based on those readings we can decide where to go from there.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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