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Another generator post [message #346803]

Sat, 24 August 2019 18:41

Silvernort

Messages: 95
Registered: June 2019
Location: Rock Springs, WI

Karma: 0

Member

On my 73 I've owned since this May, I have a Generac Guardian RV generator that had been working fine. Recently it wouldn't start and seemed to be the battery which looked kinda old. So got a new battery. charged it and gen started fine, but after a few hours died. The battery was discharged, so I jumped it and started right up. Disconnect the jump box and after about a minute the gen stops. Just to be sure I checked the fuel lines, filter and pump - all OK. Tried jumping again, started, this time left the jump box on. The gen stayed running for about 10 minutes so I disconnected the jump box and within a couple minutes the gen stopped. Next, put a trickle charger on the battery overnight. It started right up and kept running so after about half an hour I turned on the AC which worked fine. The fridge was working etc. This was yesterday, I shut it down then went out today and no go.
So it is providing power to the house fine but not charging its own starter battery. How can this be? There my also be some parasitic drain that is probably related, but not sure on that one.
Waddaya think?

Shane

Shane Harvey 1973 26' "Packer Backer", 1976 Palm Beach, 1965 Dart

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Re: Another generator post [message #346804 is a reply to message #346803]

Sat, 24 August 2019 18:53

Tom Lins

Messages: 372
Registered: February 2004
Location: St Augustine, FL

Karma: 1

Senior Member

Silvernort wrote on Sat, 24 August 2019 19:41

On my 73 I've owned since this May, I have a Generac Guardian RV generator that had been working fine. Recently it wouldn't start and seemed to be the battery which looked kinda old. So got a new battery. charged it and gen started fine, but after a few hours died. The battery was discharged, so I jumped it and started right up. Disconnect the jump box and after about a minute the gen stops. Just to be sure I checked the fuel lines, filter and pump - all OK. Tried jumping again, started, this time left the jump box on. The gen stayed running for about 10 minutes so I disconnected the jump box and within a couple minutes the gen stopped. Next, put a trickle charger on the battery overnight. It started right up and kept running so after about half an hour I turned on the AC which worked fine. The fridge was working etc. This was yesterday, I shut it down then went out today and no go.
So it is providing power to the house fine but not charging its own starter battery. How can this be? There my also be some parasitic drain that is probably related, but not sure on that one.
Waddaya think?

Shane

Sounds like your converter is not plugged into an AC outlet or it is not working. If it works like the original Onan it only makes AC and does not make DC to charge the battery.

Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/

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Re: Another generator post [message #346805 is a reply to message #346804]

Sat, 24 August 2019 19:08

Silvernort

Messages: 95
Registered: June 2019
Location: Rock Springs, WI

Karma: 0

Member

>>>Tom Lins wrote on Sat, 24 August 2019 18:53

Silvernort wrote on Sat, 24 August 2019 19:41
On my 73 I've owned since this May, I have a Generac Guardian RV generator that had been working fine. Recently it wouldn't start and seemed to be the battery which looked kinda old. So got a new battery. charged it and gen started fine, but after a few hours died. The battery was discharged, so I jumped it and started right up. Disconnect the jump box and after about a minute the gen stops. Just to be sure I checked the fuel lines, filter and pump - all OK. Tried jumping again, started, this time left the jump box on. The gen stayed running for about 10 minutes so I disconnected the jump box and within a couple minutes the gen stopped. Next, put a trickle charger on the battery overnight. It started right up and kept running so after about half an hour I turned on the AC which worked fine. The fridge was working etc. This was yesterday, I shut it down then went out today and no go.
So it is providing power to the house fine but not charging its own starter battery. How can this be? There my also be some parasitic drain that is probably related, but not sure on that one.
Waddaya think?

Shane
Sounds like your converter is not plugged into an AC outlet or it is not working. If it works like the original Onan it only makes AC and does not make DC to charge the battery.

<<<

I was just going over the schematic and it appears this unit has a winding just to charge the battery. This goes to a rectifier then to battery. I am not an elekchicken but I have a meter, just need to know what (how) to check these components out. ie on the rectifier which has three plugs (case probably ground) what do I look for.
Thanks for the help.
Shane

Shane Harvey 1973 26' "Packer Backer", 1976 Palm Beach, 1965 Dart

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Re: Another generator post [message #346806 is a reply to message #346805]

Sat, 24 August 2019 19:35

Tom Lins

Messages: 372
Registered: February 2004
Location: St Augustine, FL

Karma: 1

Senior Member

What is the model number? So I can find the manual.

Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/

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Re: [GMCnet] Another generator post [message #346808 is a reply to message #346806]

Sat, 24 August 2019 19:42

Bruce Hart

Messages: 1500
Registered: October 2011
Location: La Grange, Wyoming

Karma: 5

Senior Member

Tom, On some 73's the generator had it own separate battery. When the
generator is running take a volt meter and see if you are charging the
battery if not the voltage rectifier most likely is bad. M.W.A.G.

On Sat, Aug 24, 2019 at 6:36 PM Tom Lins via Gmclist <
gmclist@list.gmcnet.org> wrote:

> What is the model number? So I can find the manual.
> --
> Tom Lins
> St Augustine, FL
> 77 GM Rear Twin, Dry Bath, 455, FI-Tech EFI, Aluminum Radiator Quad-Bag
> Suspension
> Manuals on DVD
> GMC Dealer Training Tapes
> http://www.bdub.net/tomlins/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
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Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming

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Re: Another generator post [message #346809 is a reply to message #346805]

Sat, 24 August 2019 20:47

Tom Lins

Messages: 372
Registered: February 2004
Location: St Augustine, FL

Karma: 1

Senior Member

Silvernort wrote on Sat, 24 August 2019 20:08

>>>Tom Lins wrote on Sat, 24 August 2019 18:53
Silvernort wrote on Sat, 24 August 2019 19:41
On my 73 I've owned since this May, I have a Generac Guardian RV generator that had been working fine. Recently it wouldn't start and seemed to be the battery which looked kinda old. So got a new battery. charged it and gen started fine, but after a few hours died. The battery was discharged, so I jumped it and started right up. Disconnect the jump box and after about a minute the gen stops. Just to be sure I checked the fuel lines, filter and pump - all OK. Tried jumping again, started, this time left the jump box on. The gen stayed running for about 10 minutes so I disconnected the jump box and within a couple minutes the gen stopped. Next, put a trickle charger on the battery overnight. It started right up and kept running so after about half an hour I turned on the AC which worked fine. The fridge was working etc. This was yesterday, I shut it down then went out today and no go.
So it is providing power to the house fine but not charging its own starter battery. How can this be? There my also be some parasitic drain that is probably related, but not sure on that one.
Waddaya think?

Shane
Sounds like your converter is not plugged into an AC outlet or it is not working. If it works like the original Onan it only makes AC and does not make DC to charge the battery.
<<<

I was just going over the schematic and it appears this unit has a winding just to charge the battery. This goes to a rectifier then to battery. I am not an elekchicken but I have a meter, just need to know what (how) to check these components out. ie on the rectifier which has three plugs (case probably ground) what do I look for.
Thanks for the help.
Shane

I believe I found a wireing diagram.
Check and see what the voltage is at the battery with the generator running.
If you are not getting at least 13.5 volts it is not charging.
You need to measure from case ground to the side of the rectifier that goes to the battery.
If that also is low check each of the other two legs of the Rectifier.
If the voltage is low on the input side of the rectifier the charging winding is bad.

JMHO

Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/

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Re: Another generator post [message #346811 is a reply to message #346806]

Sat, 24 August 2019 21:24

Silvernort

Messages: 95
Registered: June 2019
Location: Rock Springs, WI

Karma: 0

Member

Tom Lins wrote on Sat, 24 August 2019 19:35

What is the model number? So I can find the manual.

02010-2

Shane Harvey 1973 26' "Packer Backer", 1976 Palm Beach, 1965 Dart

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Re: Another generator post [message #346812 is a reply to message #346809]

Sat, 24 August 2019 22:40

Tom Lins

Messages: 372
Registered: February 2004
Location: St Augustine, FL

Karma: 1

Senior Member

Check the F1 fuse also, it looks like the power goes thru the fuse to get to the battery from the rectifier.

Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/

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Re: Another generator post [message #346825 is a reply to message #346812]

Sun, 25 August 2019 10:55

Silvernort

Messages: 95
Registered: June 2019
Location: Rock Springs, WI

Karma: 0

Member

OK, what I found this morning: my brand new battery appears to have an internal short. This certainly fits the symptoms and is pretty darn frustrating. So tomorrow head back to O, O, O'Reilly's.
In checking things out, I also found the alternator works great (yeah!), and the rest of the house wiring ia a hoopty mess thanks to numerous PO's doing numerous questionable electrical add ons and mods (Boo). Ah, the joys of buying an old vehicle off Craigs list and (for my part) not being though enough in inspecting said vehicle.
Thanks for the input here. After I exchange the battery and finish checking out the gen system, I'll report back for the edification of all.

Cheers,
Shane

Shane Harvey 1973 26' "Packer Backer", 1976 Palm Beach, 1965 Dart

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Re: Another generator post [message #347164 is a reply to message #346809]

Sun, 01 September 2019 09:19

Silvernort

Messages: 95
Registered: June 2019
Location: Rock Springs, WI

Karma: 0

Member

So when a result doesn't make sense, check measuring instrument. It didn't seem likely that that new battery would be bad and I had a hunch my very old charger was not doing its job. I bought a modern 6 amp charger/maintainer and retested - battery is OK.
There was a wire, about 12g, that was connected to positive and going up into the body. On further checking it seemed this just went to the battery checking switch/meter. The problem, it was drawing pretty heavy current constantly. I don't know yet if this wire supplies anything else as the testing had to be interrupted for an appointment with the RV shop for a ball joint replacement and alignment. However, leaving this wire disconnected seemed to solve my discharge problem and other than not being able to check the charge level at the gauge panel, I haven't seen any other issues.
When I get the GMC back, guess I'll have to see what is up with that meter and whether that wire goes to something else also.

Cheers,
Shane

>>Tom Lins wrote on Sat, 24 August 2019 20:47

Silvernort wrote on Sat, 24 August 2019 20:08
>>>Tom Lins wrote on Sat, 24 August 2019 18:53
Silvernort wrote on Sat, 24 August 2019 19:41
On my 73 I've owned since this May, I have a Generac Guardian RV generator that had been working fine. Recently it wouldn't start and seemed to be the battery which looked kinda old. So got a new battery. charged it and gen started fine, but after a few hours died. The battery was discharged, so I jumped it and started right up. Disconnect the jump box and after about a minute the gen stops. Just to be sure I checked the fuel lines, filter and pump - all OK. Tried jumping again, started, this time left the jump box on. The gen stayed running for about 10 minutes so I disconnected the jump box and within a couple minutes the gen stopped. Next, put a trickle charger on the battery overnight. It started right up and kept running so after about half an hour I turned on the AC which worked fine. The fridge was working etc. This was yesterday, I shut it down then went out today and no go.
So it is providing power to the house fine but not charging its own starter battery. How can this be? There my also be some parasitic drain that is probably related, but not sure on that one.
Waddaya think?

Shane
Sounds like your converter is not plugged into an AC outlet or it is not working. If it works like the original Onan it only makes AC and does not make DC to charge the battery.
<<<

I was just going over the schematic and it appears this unit has a winding just to charge the battery. This goes to a rectifier then to battery. I am not an elekchicken but I have a meter, just need to know what (how) to check these components out. ie on the rectifier which has three plugs (case probably ground) what do I look for.
Thanks for the help.
Shane
I believe I found a wireing diagram.
Check and see what the voltage is at the battery with the generator running.
If you are not getting at least 13.5 volts it is not charging.
You need to measure from case ground to the side of the rectifier that goes to the battery.
If that also is low check each of the other two legs of the Rectifier.
If the voltage is low on the input side of the rectifier the charging winding is bad.

JMHO

Shane Harvey 1973 26' "Packer Backer", 1976 Palm Beach, 1965 Dart

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